1
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Coddington OM, Richard EC, Harber D, Pilewskie P, Woods TN, Chance K, Liu X, Sun K. The TSIS-1 Hybrid Solar Reference Spectrum. Geophys Res Lett 2021; 48:e2020GL091709. [PMID: 34219834 PMCID: PMC8244077 DOI: 10.1029/2020gl091709] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 04/12/2021] [Accepted: 04/17/2021] [Indexed: 06/12/2023]
Abstract
We present a new solar irradiance reference spectrum representative of solar minimum conditions between solar cycles 24 and 25. The Total and Spectral Solar Irradiance Sensor-1 (TSIS-1) Hybrid Solar Reference Spectrum (HSRS) is developed by applying a modified spectral ratio method to normalize very high spectral resolution solar line data to the absolute irradiance scale of the TSIS-1 Spectral Irradiance Monitor (SIM) and the CubeSat Compact SIM (CSIM). The high spectral resolution solar line data are the Air Force Geophysical Laboratory ultraviolet solar irradiance balloon observations, the ground-based Quality Assurance of Spectral Ultraviolet Measurements In Europe Fourier transform spectrometer solar irradiance observations, the Kitt Peak National Observatory solar transmittance atlas, and the semi-empirical Solar Pseudo-Transmittance Spectrum atlas. The TSIS-1 HSRS spans 202-2730 nm at 0.01 to ∼0.001 nm spectral resolution with uncertainties of 0.3% between 460 and 2365 nm and 1.3% at wavelengths outside that range.
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Affiliation(s)
- O. M. Coddington
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - E. C. Richard
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - D. Harber
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - P. Pilewskie
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
- Department for Atmospheric and Oceanic ScienceUniversity of Colorado BoulderBoulderCOUSA
| | - T. N. Woods
- Laboratory for Atmospheric and Space PhysicsUniversity of Colorado BoulderBoulderCOUSA
| | - K. Chance
- Harvard‐Smithsonian Center for AstrophysicsCambridgeMAUSA
| | - X. Liu
- Harvard‐Smithsonian Center for AstrophysicsCambridgeMAUSA
| | - K. Sun
- Department of Civil, Structural and Environmental EngineeringUniversity at BuffaloBuffaloNYUSA
- Research and Education in ENergy, Environment and Water (RENEW) InstituteUniversity at BuffaloBuffaloNYUSA
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2
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Chen L, Ng J, Omelchenko Y, Wang S. Magnetopause Reconnection and Indents Induced by Foreshock Turbulence. Geophys Res Lett 2021; 48:e2021GL093029. [PMID: 34219833 PMCID: PMC8244040 DOI: 10.1029/2021gl093029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/22/2021] [Accepted: 05/08/2021] [Indexed: 06/13/2023]
Abstract
Based on global hybrid simulation results, we predict that foreshock turbulence can reach the magnetopause and lead to reconnection as well as Earth-sized indents. Both the interplanetary magnetic field (IMF) and solar wind are constant in our simulation, and hence, all dynamics are generated by foreshock instabilities. The IMF in the simulation is mostly Sun-Earth aligned with a weak northward and zero dawn-dusk component, such that subsolar magnetopause reconnection is not expected without foreshock turbulence modifying the magnetosheath fields. We show a reconnection example to illustrate that the turbulence can create large magnetic shear angles across the magnetopause to induce local bursty reconnection. Magnetopause reconnection and indents developed from the impact of foreshock turbulence can potentially contribute to dayside loss of planetary plasmas.
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Affiliation(s)
- Li‐Jen Chen
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Jonathan Ng
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- University of MarylandCollege ParkMDUSA
| | - Yuri Omelchenko
- Trinum Research, Inc.San DiegoCAUSA
- Space Science InstituteBoulderCOUSA
| | - Shan Wang
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- University of MarylandCollege ParkMDUSA
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3
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Harvey VL, Datta‐Barua S, Pedatella NM, Wang N, Randall CE, Siskind DE, van Caspel WE. Transport of Nitric Oxide Via Lagrangian Coherent Structures Into the Top of the Polar Vortex. J Geophys Res Atmos 2021; 126:e2020JD034523. [PMID: 34221782 PMCID: PMC8243962 DOI: 10.1029/2020jd034523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/29/2021] [Accepted: 05/05/2021] [Indexed: 05/09/2023]
Abstract
The energetic particle precipitation (EPP) indirect effect (IE) refers to the downward transport of reactive odd nitrogen (NOx = NO + NO2) produced by EPP (EPP-NOx) from the polar winter mesosphere and lower thermosphere to the stratosphere where it can destroy ozone. Previous studies of the EPP IE examined NOx descent averaged over the polar region, but the work presented here considers longitudinal variations. We report that the January 2009 split Arctic vortex in the stratosphere left an imprint on the distribution of NO near the mesopause, and that the magnitude of EPP-NOx descent in the upper mesosphere depends strongly on the planetary wave (PW) phase. We focus on an 11-day case study in late January immediately following the 2009 sudden stratospheric warming during which regional-scale Lagrangian coherent structures (LCSs) formed atop the strengthening mesospheric vortex. The LCSs emerged over the north Atlantic in the vicinity of the trough of a 10-day westward traveling planetary wave. Over the next week, the LCSs acted to confine NO-rich air to polar latitudes, effectively prolonging its lifetime as it descended into the top of the polar vortex. Both a whole atmosphere data assimilation model and satellite observations show that the PW trough remained coincident in space and time with the NO-rich air as both migrated westward over the Canadian Arctic. Estimates of descent rates indicate five times stronger descent inside the PW trough compared to other longitudes. This case serves to set the stage for future climatological analysis of NO transport via LCSs.
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Affiliation(s)
- V. Lynn Harvey
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
- Department of Atmospheric and Oceanic SciencesUniversity of ColoradoBoulderCOUSA
| | - Seebany Datta‐Barua
- Department of Mechanical, Materials, and Aerospace EngineeringIllinois Institute of TechnologyChicagoILUSA
| | | | - Ningchao Wang
- Department of Atmospheric SciencesHampton UniversityHamptonVAUSA
| | - Cora E. Randall
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
- Department of Atmospheric and Oceanic SciencesUniversity of ColoradoBoulderCOUSA
| | | | - Willem E. van Caspel
- Department of PhysicsNorwegian University of Science and TechnologyNorway
- Birkeland Centre for Space Science, University of BergenBergenNorway
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4
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Lu X, Hu Y, Yang Y, Vaughan M, Palm S, Trepte C, Omar A, Lucker P, Baize R. Enabling Value Added Scientific Applications of ICESat-2 Data With Effective Removal of Afterpulses. Earth Space Sci 2021; 8:e2021EA001729. [PMID: 34222563 PMCID: PMC8244116 DOI: 10.1029/2021ea001729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/09/2021] [Accepted: 04/17/2021] [Indexed: 06/13/2023]
Abstract
The Advanced Topographic Laser Altimeter System (ATLAS) aboard the Ice, Cloud, and land Elevation Satellite-2 (ICESat-2) has been making very high resolution measurements of the Earth's surface elevation since October 2018. ATLAS uses photomultiplier tubes (PMTs) as detectors in photon counting mode, so that a single photon reflected back to the receiver triggers a detection within the ICESat-2 data acquisition system. However, one characteristic of ICESat-2 detected photons is the possible presence of afterpulses, defined as small amplitude pulses occurring after the primary signal pulse due to photon arrival. The disadvantage of these afterpulses is that they often confound the accurate measurements of low level signals following a large amplitude of signal and can degrade energy resolution and cause errors in pulse counting applications. This paper discusses and summarizes the after-pulsing effects exhibited by the ATLAS PMTs based on on-orbit measurements over different seasons and geographic regions. The potential impacts of these after-pulsing effects on altimetry and ocean subsurface retrievals are discussed.
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Affiliation(s)
- Xiaomei Lu
- Science Systems and Applications, Inc.HamptonVAUSA
- NASA Langley Research CenterHamptonVAUSA
| | | | - Yuekui Yang
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - Stephen Palm
- Science Systems and Applications, Inc.HamptonVAUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | | | - Ali Omar
- NASA Langley Research CenterHamptonVAUSA
| | - Patricia Lucker
- Science Systems and Applications, Inc.HamptonVAUSA
- NASA Langley Research CenterHamptonVAUSA
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5
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Rocchini D, Thouverai E, Marcantonio M, Iannacito M, Da Re D, Torresani M, Bacaro G, Bazzichetto M, Bernardi A, Foody GM, Furrer R, Kleijn D, Larsen S, Lenoir J, Malavasi M, Marchetto E, Messori F, Montaghi A, Moudrý V, Naimi B, Ricotta C, Rossini M, Santi F, Santos MJ, Schaepman ME, Schneider FD, Schuh L, Silvestri S, Ŝímová P, Skidmore AK, Tattoni C, Tordoni E, Vicario S, Zannini P, Wegmann M. rasterdiv-An Information Theory tailored R package for measuring ecosystem heterogeneity from space: To the origin and back. Methods Ecol Evol 2021; 12:1093-1102. [PMID: 34262682 PMCID: PMC8252722 DOI: 10.1111/2041-210x.13583] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 02/08/2021] [Indexed: 11/28/2022]
Abstract
Ecosystem heterogeneity has been widely recognized as a key ecological indicator of several ecological functions, diversity patterns and change, metapopulation dynamics, population connectivity or gene flow.In this paper, we present a new R package-rasterdiv-to calculate heterogeneity indices based on remotely sensed data. We also provide an ecological application at the landscape scale and demonstrate its power in revealing potentially hidden heterogeneity patterns.The rasterdiv package allows calculating multiple indices, robustly rooted in Information Theory, and based on reproducible open-source algorithms.
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Affiliation(s)
- Duccio Rocchini
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
- Department of Spatial Sciences, Faculty of Environmental SciencesCzech University of Life Sciences PraguePraha ‐ SuchdolCzech Republic
| | - Elisa Thouverai
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
| | - Matteo Marcantonio
- Department of Pathology, Microbiology, and ImmunologySchool of Veterinary MedicineUniversity of CaliforniaDavisCAUSA
| | | | - Daniele Da Re
- Georges Lemaître Center for Earth and Climate ResearchEarth and Life InstituteUCLouvainLouvain‐la‐NeuveBelgium
| | - Michele Torresani
- Faculty of Science and TechnologyFree University of Bolzano/BozenPiazza Universitá/Universitätsplatz 1BolzanoItaly
| | - Giovanni Bacaro
- Department of Life SciencesUniversity of TriesteTriesteItaly
| | - Manuele Bazzichetto
- EcoBio (Ecosystèmes, Biodiversité, Évolution) ‐ UMR 6553Université de RennesCNRSRennesFrance
| | | | | | - Reinhard Furrer
- Department of MathematicsUniversity of ZurichZurichSwitzerland
- Department of Computational ScienceUniversity of ZurichZurichSwitzerland
| | - David Kleijn
- Plant Ecology and Nature Conservation GroupWageningen UniversityWageningenThe Netherlands
| | - Stefano Larsen
- Unit of Computational BiologyResearch and Innovation CenterFondazione Edmund MachSan Michele all'AdigeItaly
- Department of CivilEnvironmental and Mechanical EngineeringUniversity of TrentoTrentoItaly
| | - Jonathan Lenoir
- UR “Ecologie et Dynamique des Systèmes Anthropisés” (EDYSAN, UMR 7058 CNRS‐UPJV)Université de Picardie Jules VerneAmiensFrance
| | - Marco Malavasi
- Department of Spatial Sciences, Faculty of Environmental SciencesCzech University of Life Sciences PraguePraha ‐ SuchdolCzech Republic
| | - Elisa Marchetto
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
| | - Filippo Messori
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
| | - Alessandro Montaghi
- DAGRI Department of Agriculture, Food, Environment and ForestryUniversity of FlorenceFirenzeItaly
| | - Vítězslav Moudrý
- Department of Spatial Sciences, Faculty of Environmental SciencesCzech University of Life Sciences PraguePraha ‐ SuchdolCzech Republic
| | - Babak Naimi
- Department of Geosciences and GeographyUniversity of HelsinkiHelsinkiFinland
| | - Carlo Ricotta
- Department of Environmental BiologyUniversity of Rome “La Sapienza'”RomeItaly
| | - Micol Rossini
- Remote Sensing of Environmental Dynamics LaboratoryDISATUniversitá degli Studi Milano‐BicoccaMilanoItaly
| | - Francesco Santi
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
| | - Maria J. Santos
- Department of Geography, Earth System ScienceUniversity of ZurichZurichSwitzerland
| | - Michael E. Schaepman
- Department of GeographyRemote Sensing LaboratoriesUniversity of ZurichZurichSwitzerland
| | | | - Leila Schuh
- Department of MathematicsUniversity of ZurichZurichSwitzerland
| | - Sonia Silvestri
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
| | - Petra Ŝímová
- Department of Spatial Sciences, Faculty of Environmental SciencesCzech University of Life Sciences PraguePraha ‐ SuchdolCzech Republic
| | - Andrew K. Skidmore
- Faculty of Geo‐Information Science and Earth Observation (ITC)University of TwenteEnschedeThe Netherlands
- Department of Environmental ScienceMacquarie UniversitySydneyNSWAustralia
| | - Clara Tattoni
- Department of Agriculture, Food, Environment and Forestry (DAGRI)University of FlorenceFirenzeItaly
| | - Enrico Tordoni
- Department of Life SciencesUniversity of TriesteTriesteItaly
| | - Saverio Vicario
- CNR‐IIA C/O Physics Department “M. Merlin” University of BariBariItaly
| | - Piero Zannini
- BIOME Lab, Department of Biological, Geological and Environmental SciencesAlma Mater Studiorum University of BolognaBolognaItaly
| | - Martin Wegmann
- Department of Remote SensingUniversity of WuerzburgWürzburgGermany
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6
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Follett CL, Dutkiewicz S, Forget G, Cael BB, Follows MJ. Moving ecological and biogeochemical transitions across the North Pacific. Limnol Oceanogr 2021; 66:2442-2454. [PMID: 34248205 PMCID: PMC8252044 DOI: 10.1002/lno.11763] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 12/22/2020] [Accepted: 03/17/2021] [Indexed: 06/13/2023]
Abstract
In the North Pacific Ocean, nutrient rich surface waters flow south from the subpolar gyre through a transitional region and into the subtropics. Along the way, nutrients are used, recycled, and exported, leading to lower biomass and a commensurate change in ecosystem structure moving southward. We focus on the region between the two gyres (the Transition Zone) using a coupled biophysical ocean model, remote sensing, floats, and cruise data to explore the nature of the physical, biogeochemical, and ecological fields in this region. Nonlinear interactions between biological processes and the meridional gradient in nutrient supply lead to sharp shifts across this zone. These transitions between a southern region with more uniform biological and biogeochemical properties and steep meridional gradients to the north are diagnosed from extrema in the first derivative of the properties with latitude. Some transitions like that for chlorophyll a (the transition zone chlorophyll front [TZCF]) experience large seasonal excursions while the location of the transitions in other properties moves very little. The seasonal shifts are not caused by changes in the horizontal flow field, but rather by the interaction of seasonal, depth related, forcing with the mean latitudinal gradients. Focusing on the TZCF as a case study, we express its phase velocity in terms of vertical nutrient flux and internal ecosystem processes, demonstrating their nearly equal influence on its motion. This framework of propagating biogeochemical transitions can be systematically expanded to better understand the processes that structure ecosystems and biogeochemistry in the North Pacific and beyond.
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Affiliation(s)
- Christopher L. Follett
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Stephanie Dutkiewicz
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - Gael Forget
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
| | - B. B. Cael
- National Oceanography CentreSouthamptonUK
| | - Michael J. Follows
- Department of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeMassachusettsUSA
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7
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Mitra A, Di Girolamo L, Hong Y, Zhan Y, Mueller KJ. Assessment and Error Analysis of Terra-MODIS and MISR Cloud-Top Heights Through Comparison With ISS-CATS Lidar. J Geophys Res Atmos 2021; 126:e2020JD034281. [PMID: 34221784 PMCID: PMC8244073 DOI: 10.1029/2020jd034281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/05/2021] [Accepted: 04/06/2021] [Indexed: 06/13/2023]
Abstract
Cloud-top heights (CTH) from the Multiangle Imaging Spectroradiometer (MISR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra constitute our longest-running single-platform CTH record from a stable orbit. Here, we provide the first evaluation of the Terra Level 2 CTH record against collocated International Space Station Cloud-Aerosol Transport System (CATS) lidar observations between 50ºN and 50ºS. Bias and precision of Terra CTH relative to CATS is shown to be strongly tied to cloud horizontal and vertical heterogeneity and altitude. For single-layered, unbroken, optically thick clouds observed over all altitudes, the uncertainties in MODIS and MISR CTH are -540 ± 690 m and -280 ± 370 m, respectively. The uncertainties are generally smaller for lower altitude clouds and larger for optically thin clouds. For multi-layered clouds, errors are summarized herein using both absolute CTH and CATS-layer-altitude proximity to Terra CTH. We show that MISR detects the lower cloud in a two-layered system, provided top-layer optical depth <∼0.3, but MISR low-cloud CTH errors are unaltered by the presence of thin cirrus. Systematic and random errors are propagated to explain inter-sensor disagreements, as well as to provide the first estimate of the MISR stereo-opacity bias. For MISR, altitude-dependent wind-retrieval bias (-90 to -110 m) and stereo-opacity bias (-60 to -260 m) and for MODIS, CO2-slicing bias due to geometrically thick cirrus leads to overall negative CTH bias. MISR's precision is largely driven by precision in retrieved wind-speed (3.7 m s-1), whereas MODIS precision is driven by forward-modeling uncertainty.
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Affiliation(s)
- Arka Mitra
- University of IllinoisUrbana‐ChampaignILUSA
| | | | - Yulan Hong
- University of IllinoisUrbana‐ChampaignILUSA
| | - Yizhe Zhan
- University of IllinoisUrbana‐ChampaignILUSA
- Metservice Ltd.WellingtonNew Zealand
| | - Kevin J. Mueller
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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8
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Topp SN, Pavelsky TM, Dugan HA, Yang X, Gardner J, Ross MR. Shifting Patterns of Summer Lake Color Phenology in Over 26,000 US Lakes. Water Resour Res 2021; 57:e2020WR029123. [PMID: 34219822 PMCID: PMC8244058 DOI: 10.1029/2020wr029123] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 04/08/2021] [Accepted: 05/06/2021] [Indexed: 06/13/2023]
Abstract
Lakes are often defined by seasonal cycles. The seasonal timing, or phenology, of many lake processes are changing in response to human activities. However, long-term records exist for few lakes, and extrapolating patterns observed in these lakes to entire landscapes is exceedingly difficult using the limited number of available in situ observations. Limited landscape-level observations mean we do not know how common shifts in lake phenology are at macroscales. Here, we use a new remote sensing data set, LimnoSat-US, to analyze U.S. summer lake color phenology between 1984 and 2020 across more than 26,000 lakes. Our results show that summer lake color seasonality can be generalized into five distinct phenology groups that follow well-known patterns of phytoplankton succession. The frequency with which lakes transition from one phenology group to another is tied to lake and landscape level characteristics. Lakes with high inflows and low variation in their seasonal surface area are generally more stable, while lakes in areas with high interannual variations in climate and catchment population density show less stability. Our results reveal previously unexamined spatiotemporal patterns in lake seasonality and demonstrate the utility of LimnoSat-US, which, with over 22 million remote sensing observations of lakes, creates novel opportunities to examine changing lake ecosystems at a national scale.
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Affiliation(s)
- Simon N. Topp
- Department of Geological SciencesUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Tamlin M. Pavelsky
- Department of Geological SciencesUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - Hilary A. Dugan
- Center for LimnologyUniversity of Wisconsin‐MadisonMadisonWIUSA
| | - Xiao Yang
- Department of Geological SciencesUniversity of North Carolina at Chapel HillChapel HillNCUSA
| | - John Gardner
- Department of Geological SciencesUniversity of North Carolina at Chapel HillChapel HillNCUSA
- Department of Geology and Environmental ScienceUniversity of PittsburghPittsburghPAUSA
| | - Matthew R.V. Ross
- Department of Ecosystem Science and SustainabilityColorado State UniversityFort CollinsCOUSA
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9
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Campbell MF, Celenza TJ, Schmitt F, Schwede JW, Bargatin I. Progress Toward High Power Output in Thermionic Energy Converters. Adv Sci (Weinh) 2021; 8:2003812. [PMID: 33977055 PMCID: PMC8097403 DOI: 10.1002/advs.202003812] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/25/2020] [Indexed: 06/12/2023]
Abstract
Thermionic energy converters are solid-state heat engines that have the potential to produce electricity with efficiencies of over 30% and area-specific power densities of 100 Wcm-2. Despite this prospect, no prototypes reported in the literature have achieved true efficiencies close to this target, and many of the most recent investigations report power densities on the order of mWcm-2 or less. These discrepancies stem in part from the low-temperature (<1300 K) test conditions used to evaluate these devices, the large vacuum gap distances (25-100 µm) employed by these devices, and material challenges related to these devices' electrodes. This review will argue that, for feasible electrode work functions available today, efficient performance requires generating output power densities of >1 Wcm-2 and employing emitter temperatures of 1300 K or higher. With this result in mind, this review provides an overview of historical and current design architectures and comments on their capacity to realize the efficiency and power potential of thermionic energy converters. Also emphasized is the importance of using standardized efficiency metrics to report thermionic energy converter performance data.
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Affiliation(s)
- Matthew F. Campbell
- Department of Mechanical Engineering and Applied MechanicsUniversity of PennsylvaniaPhiladelphiaPA19104USA
| | - Thomas J. Celenza
- Department of Mechanical Engineering and Applied MechanicsUniversity of PennsylvaniaPhiladelphiaPA19104USA
| | | | | | - Igor Bargatin
- Department of Mechanical Engineering and Applied MechanicsUniversity of PennsylvaniaPhiladelphiaPA19104USA
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10
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McKinna LIW, Cetinić I, Werdell PJ. Development and Validation of an Empirical Ocean Color Algorithm with Uncertainties: A Case Study with the Particulate Backscattering Coefficient. J Geophys Res Oceans 2021; 126:e2021JC017231. [PMID: 34221787 PMCID: PMC8244078 DOI: 10.1029/2021jc017231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/01/2021] [Accepted: 04/10/2021] [Indexed: 06/13/2023]
Abstract
We explored how algorithm (model) and in situ measurement (observation) uncertainties can effectively be incorporated into empirical ocean color model development and assessment. In this study we focused on methods for deriving the particulate backscattering coefficient at 555 nm, b bp (555) (m-1). We developed a simple empirical algorithm for deriving b bp (555) as a function of a remote sensing reflectance line height (LH) metric. Model training was performed using a high-quality bio-optical dataset that contains coincident in situ measurements of the spectral remote sensing reflectances, R rs (λ) (sr-1), and the spectral particulate backscattering coefficients, b bp (λ). The LH metric used is defined as the magnitude of R rs (555) relative to a linear baseline drawn between R rs (490) and R rs (670). Using an independent validation dataset, we compared the skill of the LH-based model with two other models. We used contemporary validation metrics, including bias and mean absolute error (MAE), that were corrected for model and observation uncertainties. The results demonstrated that measurement uncertainties do indeed impact contemporary validation metrics such as mean bias and MAE. Zeta-scores and z-tests for overlapping confidence intervals were also explored as potential methods for assessing model skill.
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Affiliation(s)
| | - Ivona Cetinić
- GESTAR/USRAColumbiaMDUSA
- NASA Goddard Flight CenterGreenbeltMDUSA
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11
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Gorris ME, Anenberg SC, Goldberg DL, Kerr GH, Stowell JD, Tong D, Zaitchik BF. Shaping the Future of Science: COVID-19 Highlighting the Importance of GeoHealth. Geohealth 2021; 5:e2021GH000412. [PMID: 34084984 PMCID: PMC8144838 DOI: 10.1029/2021gh000412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 04/26/2021] [Accepted: 05/02/2021] [Indexed: 06/12/2023]
Abstract
From the heated debates over the airborne transmission of the novel coronavirus to the abrupt Earth system changes caused by the sudden lockdowns, the dire circumstances resulting from the coronavirus disease 2019 (COVID-19) pandemic have brought the field of GeoHealth to the forefront of visibility in science and policy. The pandemic has inadvertently provided an opportunity to study how human response has impacted the Earth system, how the Earth system may impact the pandemic, and the capacity of GeoHealth to inform real-time policy. The lessons learned throughout our responses to the COVID-19 pandemic are shaping the future of GeoHealth.
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Affiliation(s)
- Morgan E. Gorris
- Information Systems and ModelingLos Alamos National LaboratoryLos AlamosNMUSA
| | - Susan C. Anenberg
- Department of Environmental and Occupational HealthMilken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
| | - Daniel L. Goldberg
- Department of Environmental and Occupational HealthMilken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
| | - Gaige Hunter Kerr
- Department of Environmental and Occupational HealthMilken Institute School of Public HealthGeorge Washington UniversityWashingtonDCUSA
| | - Jennifer D. Stowell
- Department of Environmental HealthBoston University School of Public HealthBostonMAUSA
| | - Daniel Tong
- Department of Atmospheric, Oceanic, & Earth SciencesGeorge Mason UniversityFairfaxVAUSA
| | - Benjamin F. Zaitchik
- Department of Earth and Planetary SciencesJohns Hopkins UniversityBaltimoreMDUSA
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12
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Jasinski JM, Cassidy TA, Raines JM, Milillo A, Regoli LH, Dewey R, Slavin JA, Mangano V, Murphy N. Photoionization Loss of Mercury's Sodium Exosphere: Seasonal Observations by MESSENGER and the THEMIS Telescope. Geophys Res Lett 2021; 48:e2021GL092980. [PMID: 34219841 PMCID: PMC8243941 DOI: 10.1029/2021gl092980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/19/2021] [Accepted: 03/23/2021] [Indexed: 06/02/2023]
Abstract
We present the first investigation and quantification of the photoionization loss process to Mercury's sodium exosphere from spacecraft and ground-based observations. We analyze plasma and neutral sodium measurements from NASA's MESSENGER spacecraft and the THEMIS telescope. We find that the sodium ion (Na+) content and therefore the significance of photoionization varies with Mercury's orbit around the Sun (i.e., true anomaly angle: TAA). Na+ production is affected by the neutral sodium solar-radiation acceleration loss process. More Na+ was measured on the inbound leg of Mercury's orbit at 180°-360° TAA because less neutral sodium is lost downtail from radiation acceleration. Calculations using results from observations show that the photoionization loss process removes ∼1024 atoms/s from the sodium exosphere (maxima of 4 × 1024 atoms/s), showing that modeling efforts underestimate this loss process. This is an important result as it shows that photoionization is a significant loss process and larger than loss from radiation acceleration.
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Affiliation(s)
- Jamie M. Jasinski
- NASA Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Timothy A. Cassidy
- Laboratory of Atmospheric and Space SciencesUniversity of Colorado BoulderBoulderCOUSA
| | - Jim M. Raines
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMIUSA
| | | | | | - Ryan Dewey
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMIUSA
| | - James A. Slavin
- Department of Climate and Space Sciences and EngineeringUniversity of MichiganAnn ArborMIUSA
| | | | - Neil Murphy
- NASA Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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13
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Keller CA, Knowland KE, Duncan BN, Liu J, Anderson DC, Das S, Lucchesi RA, Lundgren EW, Nicely JM, Nielsen E, Ott LE, Saunders E, Strode SA, Wales PA, Jacob DJ, Pawson S. Description of the NASA GEOS Composition Forecast Modeling System GEOS-CF v1.0. J Adv Model Earth Syst 2021; 13:e2020MS002413. [PMID: 34221240 PMCID: PMC8244029 DOI: 10.1029/2020ms002413] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/18/2021] [Accepted: 03/16/2021] [Indexed: 05/11/2023]
Abstract
The Goddard Earth Observing System composition forecast (GEOS-CF) system is a high-resolution (0.25°) global constituent prediction system from NASA's Global Modeling and Assimilation Office (GMAO). GEOS-CF offers a new tool for atmospheric chemistry research, with the goal to supplement NASA's broad range of space-based and in-situ observations. GEOS-CF expands on the GEOS weather and aerosol modeling system by introducing the GEOS-Chem chemistry module to provide hindcasts and 5-days forecasts of atmospheric constituents including ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and fine particulate matter (PM2.5). The chemistry module integrated in GEOS-CF is identical to the offline GEOS-Chem model and readily benefits from the innovations provided by the GEOS-Chem community. Evaluation of GEOS-CF against satellite, ozonesonde and surface observations for years 2018-2019 show realistic simulated concentrations of O3, NO2, and CO, with normalized mean biases of -0.1 to 0.3, normalized root mean square errors between 0.1-0.4, and correlations between 0.3-0.8. Comparisons against surface observations highlight the successful representation of air pollutants in many regions of the world and during all seasons, yet also highlight current limitations, such as a global high bias in SO2 and an overprediction of summertime O3 over the Southeast United States. GEOS-CF v1.0 generally overestimates aerosols by 20%-50% due to known issues in GEOS-Chem v12.0.1 that have been addressed in later versions. The 5-days forecasts have skill scores comparable to the 1-day hindcast. Model skills can be improved significantly by applying a bias-correction to the surface model output using a machine-learning approach.
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Affiliation(s)
- Christoph A. Keller
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | - K. Emma Knowland
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | | | - Junhua Liu
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | - Daniel C. Anderson
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | - Sampa Das
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | - Robert A. Lucchesi
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Science Systems and Applications, Inc.LanhamMDUSA
| | | | - Julie M. Nicely
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Earth System Science Interdisciplinary CenterUniversity of MarylandCollege ParkLanhamMDUSA
| | - Eric Nielsen
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Science Systems and Applications, Inc.LanhamMDUSA
| | | | - Emily Saunders
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Science Systems and Applications, Inc.LanhamMDUSA
| | - Sarah A. Strode
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | - Pamela A. Wales
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Universities Space Research AssociationColumbiaMDUSA
| | - Daniel J. Jacob
- School of Engineering and Applied SciencesHarvard UniversityCambridgeMAUSA
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14
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Sapoval N, Mahmoud M, Jochum MD, Liu Y, Elworth RAL, Wang Q, Albin D, Ogilvie HA, Lee MD, Villapol S, Hernandez KM, Maljkovic Berry I, Foox J, Beheshti A, Ternus K, Aagaard KM, Posada D, Mason CE, Sedlazeck FJ, Treangen TJ. SARS-CoV-2 genomic diversity and the implications for qRT-PCR diagnostics and transmission. Genome Res 2021; 31:635-644. [PMID: 33602693 PMCID: PMC8015855 DOI: 10.1101/gr.268961.120] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 02/12/2021] [Indexed: 12/23/2022]
Abstract
The COVID-19 pandemic has sparked an urgent need to uncover the underlying biology of this devastating disease. Though RNA viruses mutate more rapidly than DNA viruses, there are a relatively small number of single nucleotide polymorphisms (SNPs) that differentiate the main SARS-CoV-2 lineages that have spread throughout the world. In this study, we investigated 129 RNA-seq data sets and 6928 consensus genomes to contrast the intra-host and inter-host diversity of SARS-CoV-2. Our analyses yielded three major observations. First, the mutational profile of SARS-CoV-2 highlights intra-host single nucleotide variant (iSNV) and SNP similarity, albeit with differences in C > U changes. Second, iSNV and SNP patterns in SARS-CoV-2 are more similar to MERS-CoV than SARS-CoV-1. Third, a significant fraction of insertions and deletions contribute to the genetic diversity of SARS-CoV-2. Altogether, our findings provide insight into SARS-CoV-2 genomic diversity, inform the design of detection tests, and highlight the potential of iSNVs for tracking the transmission of SARS-CoV-2.
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Affiliation(s)
- Nicolae Sapoval
- Department of Computer Science, Rice University, Houston, Texas 77005, USA
| | - Medhat Mahmoud
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Michael D Jochum
- Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas 77030, USA
| | - Yunxi Liu
- Department of Computer Science, Rice University, Houston, Texas 77005, USA
| | - R A Leo Elworth
- Department of Computer Science, Rice University, Houston, Texas 77005, USA
| | - Qi Wang
- Systems, Synthetic, and Physical Biology (SSPB) Graduate Program, Rice University, Houston, Texas 77005, USA
| | - Dreycey Albin
- Systems, Synthetic, and Physical Biology (SSPB) Graduate Program, Rice University, Houston, Texas 77005, USA
| | - Huw A Ogilvie
- Department of Computer Science, Rice University, Houston, Texas 77005, USA
| | - Michael D Lee
- Exobiology Branch, NASA Ames Research Center, Mountain View, California 94043, USA
- Blue Marble Space Institute of Science, Seattle, Washington 98104, USA
| | - Sonia Villapol
- Department of Neurosurgery, Houston Methodist Research Institute, Houston, Texas 77030, USA
| | - Kyle M Hernandez
- Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA
- Center for Translational Data Science, University of Chicago, Chicago, Illinois 60637, USA
| | | | - Jonathan Foox
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York 10021, USA
| | - Afshin Beheshti
- KBR, Space Biosciences Division, NASA Ames Research Center, Moffett Field, California 94035, USA
| | | | - Kjersti M Aagaard
- Department of Obstetrics and Gynecology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas 77030, USA
| | - David Posada
- CINBIO, Universidade de Vigo, 36310 Vigo, Spain
- Department of Biochemistry, Genetics, and Immunology, Universidade de Vigo, 36310 Vigo, Spain
- Galicia Sur Health Research Institute (IIS Galicia Sur), SERGAS-UVIGO, 36213 Vigo, Spain
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, New York 10021, USA
| | - Fritz J Sedlazeck
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Todd J Treangen
- Department of Computer Science, Rice University, Houston, Texas 77005, USA
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15
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Twardochleb L, Hiltner E, Pyne M, Zarnetske P. Freshwater insects CONUS: A database of freshwater insect occurrences and traits for the contiguous United States. Glob Ecol Biogeogr 2021; 30:826-841. [PMID: 33776581 PMCID: PMC7986927 DOI: 10.1111/geb.13257] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/09/2020] [Accepted: 11/23/2020] [Indexed: 05/13/2023]
Abstract
MOTIVATION Freshwater insects comprise 60% of freshwater animal diversity; they are widely used to assess water quality, and they provide prey for numerous freshwater and terrestrial taxa. Our knowledge of the distribution of freshwater insect diversity in the USA is incomplete because we lack comprehensive, standardized data on their distributions and functional traits at the scale of the contiguous United States (CONUS). We fill this knowledge gap by presenting Freshwater insects CONUS: A database of freshwater insect occurrences and traits for the contiguous United States. This database includes 2.05 million occurrence records for 932 genera in the major freshwater insect orders, at 51,044 stream locations sampled between 2001 and 2018 by federal and state biological monitoring programmes. Compared with existing open-access databases, we tripled the number of occurrence records and locations and added records for 118 genera. We also present life-history, dispersal, morphological and ecological traits and trait affinities (analogous to fuzzy-coded traits) for 1,007 stream insect genera, assembled from existing databases, reference books and the primary literature. We nearly doubled the number of traits for 11 trait groups and added traits for 180 genera that were not available from open-access databases. Our database, Freshwater insects CONUS, facilitates the mapping of freshwater insect taxonomic and functional diversity and, when paired with environmental data, will provide a powerful resource for quantifying how the environment shapes stream insect diversity and taxon-specific distributions. MAIN TYPES OF VARIABLES CONTAINED Georeferenced occurrence records and traits for stream insects. SPATIAL LOCATION AND GRAIN Contiguous United States at a grain of c. 1 m2. TIME PERIOD AND GRAIN Occurrence records from January 2001 to December 2018, with 1-day temporal resolution. Traits from January 1911 to December 2018. MAJOR TAXA AND LEVEL OF MEASUREMENT Genera from the orders Coleoptera, Diptera, Ephemeroptera, Hemiptera, Lepidoptera, Megaloptera, Neuroptera, Odonata, Plecoptera and Trichoptera. SOFTWARE FORMAT .csv.
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Affiliation(s)
- Laura Twardochleb
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMIUSA
- Ecology, Evolutionary Biology and Behavior ProgramMichigan State UniversityEast LansingMIUSA
| | - Ethan Hiltner
- Department of Fisheries and WildlifeMichigan State UniversityEast LansingMIUSA
| | - Matthew Pyne
- Department of BiologyLamar UniversityBeaumontTXUSA
| | - Phoebe Zarnetske
- Ecology, Evolutionary Biology and Behavior ProgramMichigan State UniversityEast LansingMIUSA
- Department of Integrative BiologyMichigan State UniversityEast LansingMIUSA
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16
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McGarry JF, Carabajal CC, Saba JL, Reese AR, Holland ST, Palm SP, Swinski JA, Golder JE, Liiva PM. ICESat-2/ATLAS Onboard Flight Science Receiver Algorithms: Purpose, Process, and Performance. Earth Space Sci 2021; 8:e2020EA001235. [PMID: 34222559 PMCID: PMC8243955 DOI: 10.1029/2020ea001235] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 08/21/2020] [Accepted: 10/25/2020] [Indexed: 06/13/2023]
Abstract
The Advanced Topographic Laser Altimetry System (ATLAS) is the sole instrument on the Ice, Cloud, and land Elevation Satellite 2 (ICESat-2). Without some method of reducing the transmitted data, the volume of ATLAS telemetry would far exceed the normal X-band downlink capability or require many more ground station contacts. The ATLAS Onboard Flight Science Receiver Algorithms (hereinafter Receiver Algorithms or Algorithms) control the amount of science data that is telemetered from the instrument, limiting the data volume by distinguishing surface echoes from background noise, and allowing the instrument to telemeter data from only a small vertical region about the signal. This is accomplished through the transfer of the spacecraft's location and attitude to the instrument every second, use of an onboard Digital Elevation Model, implementation of signal processing techniques, and use of onboard relief and surface type reference maps. Extensive ground testing verified the performance of the Algorithms. On-orbit analysis shows that the Algorithms are working as expected from the ground testing; they are performing well and meeting the mission requirements.
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Affiliation(s)
| | | | - J. L. Saba
- Science Systems and Applications, IncLanhamMDUSA
| | | | | | - S. P. Palm
- Science Systems and Applications, IncLanhamMDUSA
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17
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Rignot E, An L, Chauche N, Morlighem M, Jeong S, Wood M, Mouginot J, Willis JK, Klaucke I, Weinrebe W, Muenchow A. Retreat of Humboldt Gletscher, North Greenland, Driven by Undercutting From a Warmer Ocean. Geophys Res Lett 2021; 48:e2020GL091342. [PMID: 34219836 PMCID: PMC8243930 DOI: 10.1029/2020gl091342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/17/2021] [Accepted: 01/21/2021] [Indexed: 06/13/2023]
Abstract
Humboldt Gletscher is a 100-km wide, slow-moving glacier in north Greenland which holds a 19-cm global sea level equivalent. Humboldt has been the fourth largest contributor to sea level rise since 1972 but the cause of its mass loss has not been elucidated. Multi-beam echo sounding data collected in 2019 indicate a seabed 200 m deeper than previously known. Conductivity temperature depth data reveal the presence of warm water of Atlantic origin at 0°C at the glacier front and a warming of the ocean waters by 0.9 ± 0.1°C since 1962. Using an ocean model, we reconstruct grounded ice undercutting by the ocean, combine it with calculated retreat caused by ice thinning to floatation, and are able to fully explain the observed retreat. Two thirds of the retreat are caused by undercutting of grounded ice, which is a physical process not included in most ice sheet models.
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Affiliation(s)
- Eric Rignot
- Department Earth System ScienceUniversity of California IrvineIrvineCAUSA
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Lu An
- Department Earth System ScienceUniversity of California IrvineIrvineCAUSA
| | | | - Mathieu Morlighem
- Department Earth System ScienceUniversity of California IrvineIrvineCAUSA
| | - Seongsu Jeong
- Department Earth System ScienceUniversity of California IrvineIrvineCAUSA
| | - Michael Wood
- Department Earth System ScienceUniversity of California IrvineIrvineCAUSA
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jeremie Mouginot
- Department Earth System ScienceUniversity of California IrvineIrvineCAUSA
- Institut des Geosciences de l'EnvironnementUniversite Grenoble‐AlpesCNRSGrenobleFrance
| | - Josh K. Willis
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Ingo Klaucke
- GEOMAR Helmholtz Centre for Ocean Research KielKielGermany
| | | | - Andreas Muenchow
- School of Marine Science and PolicyUniversity of DelawareNewarkDEUSA
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18
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Youngflesh C, Jones FM, Lynch HJ, Arthur J, Ročkaiová Z, Torsey HR, Hart T. Large-scale assessment of intra- and inter-annual breeding success using a remote camera network. Remote Sens Ecol Conserv 2021; 7:97-108. [PMID: 33889421 PMCID: PMC8048998 DOI: 10.1002/rse2.171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 04/06/2020] [Accepted: 05/21/2020] [Indexed: 06/12/2023]
Abstract
Changes in the physical environment along the Antarctic Peninsula have been among the most rapid anywhere on the planet. In concert with environmental change, the potential for direct human disturbance resulting from tourism, scientific programs, and commercial fisheries continues to rise in the region. While seabirds, such as the gentoo penguin Pygoscelis papua, are commonly used to assess the impact of these disturbances on natural systems, research efforts are often hampered by limited spatial coverage and lack of temporal resolution. Using a large-scale remote time-lapse camera network and a modeling framework adapted from capture-recapture studies, we assess drivers of intra- and inter-annual dynamics in gentoo penguin breeding success across nearly the entire species' range in the Atlantic sector of the Southern Ocean. We quantify the precise timing of egg/chick mortality within each season and examine the role of precipitation events, tourism visitation, and fishing activity for Antarctic krill Euphausia superba (a principal prey resource in the Antarctic) in these processes. We find that nest failure rates are higher in the egg than the chick stage and that neither krill fishing nor tourism visitation had a strong effect on gentoo penguin breeding success. While precipitation events had, on average, little effect on nest mortality, results suggest that extreme weather events can precipitate sharp increases in nest failure. This study highlights the importance of continuous ecosystem monitoring, facilitated here by remote time-lapse cameras, in understanding ecological responses to environmental stressors, particularly with regard to the timing of events such as extreme weather.
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Affiliation(s)
- Casey Youngflesh
- Department of Ecology and Evolutionary BiologyUniversity of CaliforniaLos AngelesCA90095USA
| | - Fiona M. Jones
- Department of ZoologyUniversity of OxfordOxfordOX1 3SZUK
| | - Heather J. Lynch
- Institute for Advanced Computational ScienceStony Brook UniversityStony BrookNY11794USA
| | - Joan Arthur
- ZooniverseDepartment of PhysicsUniversity of OxfordOxfordOX1 3RHUK
| | - Zuzana Ročkaiová
- ZooniverseDepartment of PhysicsUniversity of OxfordOxfordOX1 3RHUK
| | - Holly R. Torsey
- ZooniverseDepartment of PhysicsUniversity of OxfordOxfordOX1 3RHUK
| | - Tom Hart
- Department of ZoologyUniversity of OxfordOxfordOX1 3SZUK
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19
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Huang X, Runkle BRK, Isbell M, Moreno‐García B, McNairn H, Reba ML, Torbick N. Rice Inundation Assessment Using Polarimetric UAVSAR Data. Earth Space Sci 2021; 8:e2020EA001554. [PMID: 33791393 PMCID: PMC7988656 DOI: 10.1029/2020ea001554] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/11/2021] [Accepted: 01/15/2021] [Indexed: 05/26/2023]
Abstract
Irrigated rice requires intense water management under typical agronomic practices. Cost effective tools to improve the efficiency and assessment of water use is a key need for industry and resource managers to scale ecosystem services. In this research we advance model-based decomposition and machine learning to map inundated rice using time-series polarimetric, L-band Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) observations. Simultaneous ground truth observations recorded water depth inundation during the 2019 crop season using instrumented fields across the study site in Arkansas, USA. A three-component model-based decomposition generated metrics representing surface-, double bounce-, and volume-scattering along with a shape factor, randomness factor, and the Radar Vegetation Index (RVI). These physically meaningful metrics characterized crop inundation status independent of growth stage including under dense canopy cover. Machine learning (ML) comparisons employed Random Forest (RF) using the UAVSAR derived parameters to identify cropland inundation status across the region. Outcomes show that RVI, proportion of the double-bounce within total scattering, and the relative comparison between the double-bounce and the volume scattering have moderate to strong mechanistic ability to identify rice inundation status with Overall Accuracy (OA) achieving 75%. The use of relative ratios further helped mitigate the impacts of far range incidence angles. The RF approach, which requires training data, achieved a higher OA and Kappa of 88% and 71%, respectively, when leveraging multiple SAR parameters. Thus, the combination of physical characterization and ML provides a powerful approach to retrieving cropland inundation under the canopy. The growth of polarimetric L-band availability should enhance cropland inundation metrics beyond open water that are required for tracking water quantity at field scale over large areas.
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Affiliation(s)
| | - Benjamin R. K. Runkle
- Department of Biological & Agricultural EngineeringUniversity of ArkansasFayettevilleARUSA
| | | | - Beatriz Moreno‐García
- Department of Biological & Agricultural EngineeringUniversity of ArkansasFayettevilleARUSA
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20
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Seyednasrollah B, Bowling DR, Cheng R, Logan BA, Magney TS, Frankenberg C, Yang JC, Young AM, Hufkens K, Arain MA, Black TA, Blanken PD, Bracho R, Jassal R, Hollinger DY, Law BE, Nesic Z, Richardson AD. Seasonal variation in the canopy color of temperate evergreen conifer forests. New Phytol 2021; 229:2586-2600. [PMID: 33118171 PMCID: PMC7898516 DOI: 10.1111/nph.17046] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/13/2020] [Indexed: 05/07/2023]
Abstract
Evergreen conifer forests are the most prevalent land cover type in North America. Seasonal changes in the color of evergreen forest canopies have been documented with near-surface remote sensing, but the physiological mechanisms underlying these changes, and the implications for photosynthetic uptake, have not been fully elucidated. Here, we integrate on-the-ground phenological observations, leaf-level physiological measurements, near surface hyperspectral remote sensing and digital camera imagery, tower-based CO2 flux measurements, and a predictive model to simulate seasonal canopy color dynamics. We show that seasonal changes in canopy color occur independently of new leaf production, but track changes in chlorophyll fluorescence, the photochemical reflectance index, and leaf pigmentation. We demonstrate that at winter-dormant sites, seasonal changes in canopy color can be used to predict the onset of canopy-level photosynthesis in spring, and its cessation in autumn. Finally, we parameterize a simple temperature-based model to predict the seasonal cycle of canopy greenness, and we show that the model successfully simulates interannual variation in the timing of changes in canopy color. These results provide mechanistic insight into the factors driving seasonal changes in evergreen canopy color and provide opportunities to monitor and model seasonal variation in photosynthetic activity using color-based vegetation indices.
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Affiliation(s)
- Bijan Seyednasrollah
- School of Informatics, Computing & Cyber SystemsNorthern Arizona UniversityFlagstaffAZ86011USA
- Center for Ecosystem Science and SocietyNorthern Arizona UniversityFlagstaffAZ86011USA
| | - David R. Bowling
- School of Biological SciencesUniversity of UtahSalt Lake CityUT84112USA
| | - Rui Cheng
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCA91125USA
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCA91125USA
| | | | - Troy S. Magney
- Department of Plant SciencesUniversity of California DavisDavisCA95616USA
| | - Christian Frankenberg
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCA91125USA
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCA91125USA
| | - Julia C. Yang
- School of Biological SciencesUniversity of UtahSalt Lake CityUT84112USA
| | - Adam M. Young
- School of Informatics, Computing & Cyber SystemsNorthern Arizona UniversityFlagstaffAZ86011USA
- Center for Ecosystem Science and SocietyNorthern Arizona UniversityFlagstaffAZ86011USA
| | - Koen Hufkens
- Computational & Applied Vegetation Ecology LabGhent UniversityGhent9000Belgium
- INRAUMR ISPAVillenave d’Ornon75011France
| | - M. Altaf Arain
- School of Earth, Environment and Society and McMaster Center for Climate ChangeMcMaster UniversityHamiltonONL8S 4K1Canada
| | - T. Andrew Black
- Faculty of Land and Food SystemsUniversity of British ColumbiaVancouverBCV6T 1Z4Canada
| | | | - Rosvel Bracho
- School of Forest Resources and ConservationUniversity of FloridaGainesvilleFL32611USA
| | - Rachhpal Jassal
- Faculty of Land and Food SystemsUniversity of British ColumbiaVancouverBCV6T 1Z4Canada
| | | | - Beverly E. Law
- College of ForestryOregon State UniversityCorvallisOR97330USA
| | - Zoran Nesic
- Faculty of Land and Food SystemsUniversity of British ColumbiaVancouverBCV6T 1Z4Canada
| | - Andrew D. Richardson
- School of Informatics, Computing & Cyber SystemsNorthern Arizona UniversityFlagstaffAZ86011USA
- Center for Ecosystem Science and SocietyNorthern Arizona UniversityFlagstaffAZ86011USA
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21
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Velbel MA, Zolensky ME. Thermal metamorphism of CM chondrites: A dehydroxylation-based peak-temperature thermometer and implications for sample return from asteroids Ryugu and Bennu. Meteorit Planet Sci 2021; 56:546-585. [PMID: 34262245 PMCID: PMC8252763 DOI: 10.1111/maps.13636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 01/17/2021] [Indexed: 06/13/2023]
Abstract
The target bodies of C-complex asteroid sample return missions are carbonaceous chondrite-like near-Earth asteroids (NEAs), chosen for the abundance and scientific importance of their organic compounds and "hydrous" (including hydroxylated) minerals, such as serpentine-group phyllosilicates. Science objectives include returning samples of pristine carbonaceous regolith from asteroids for study of the nature, history, and distribution of its constituent minerals, organic material, and other volatiles. Heating after the natural aqueous alteration that formed the abundant phyllosilicates in CM and similar carbonaceous chondrites dehydroxylated them and altered or decomposed other volumetrically minor constituents (e.g., carbonates, sulfides, organic molecules; Tonui et al. 2003, 2014). We propose a peak-temperature thermometer based on dehydroxylation as measured by analytical totals from electron probe microanalysis (EPMA) of matrices in a number of heated and aqueously altered (but not further heated) CM chondrites. Some CM lithologies in Maribo and Sutter's Mill do not exhibit the matrix dehydroxylation expected for surface temperatures expected from insolation of meteoroids with their known orbital perihelia. This suggests that insolated-heated meteoroid surfaces were lost by ablation during passage through Earth's atmosphere, and that insolation-heated material is more likely to be encountered among returned asteroid regolith samples than in meteorites. More generally, several published lines of evidence suggest that episodic heating of some CM material, most likely by impacts, continued intermittently and locally up to billions of years after assembly and early heating of ancestral CM chondrite bodies. Mission spectroscopic measures of hydration can be used to estimate the extent of dehydroxylation, and the new dehydroxylation thermometer can be used directly to select fragments of returned samples most likely to contain less thermally altered inventories of primitive organic molecules.
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Affiliation(s)
- Michael A. Velbel
- Department of Earth and Environmental SciencesMichigan State University288 Farm Lane, Room 207, Natural Sciences BuildingEast LansingMichigan48824–1115USA
- Division of MeteoritesDepartment of Mineral SciencesNational Museum of Natural HistorySmithsonian InstitutionWashingtonDistrict of Columbia20013–7012USA
| | - Michael E. Zolensky
- X12 Astromaterials Research and Exploration ScienceNASA Johnson Space CenterHoustonTexas77058USA
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22
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Silvestro S, Pacifici A, Salese F, Vaz D, Neesemann A, Tirsch D, Popa C, Pajola M, Franzese G, Mongelluzzo G, Ruggeri A, Cozzolino F, Porto C, Esposito F. Periodic Bedrock Ridges at the ExoMars 2022 Landing Site: Evidence for a Changing Wind Regime. Geophys Res Lett 2021; 48:e2020GL091651. [PMID: 33776161 PMCID: PMC7988568 DOI: 10.1029/2020gl091651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/21/2020] [Accepted: 12/23/2020] [Indexed: 06/12/2023]
Abstract
Wind-formed features are abundant in Oxia Planum (Mars), the landing site of the 2022 ExoMars mission, which shows geological evidence for a past wet environment. Studies of aeolian bedforms at the landing site were focused on assessing the risk for rover trafficability, however their potential in recording climatic fluctuations has not been explored. Here we show that the landing site experienced multiple climatic changes in the Amazonian, which are recorded by an intriguing set of ridges that we interpret as Periodic Bedrock Ridges (PBRs). Clues for a PBR origin result from ridge regularity, defect terminations, and the presence of preserved megaripples detaching from the PBRs. PBR orientation differs from superimposed transverse aeolian ridges pointing toward a major change in wind regime. Our results provide constrains on PBR formation mechanisms and offer indications on paleo winds that will be crucial for understanding the landing site geology.
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Affiliation(s)
- S. Silvestro
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
- Carl Sagan CenterSETI InstituteMountain ViewCAUSA
| | - A. Pacifici
- International Research School of Planetary SciencesUniversità Gabriele D'AnnunzioPescaraItaly
| | - F. Salese
- International Research School of Planetary SciencesUniversità Gabriele D'AnnunzioPescaraItaly
- Centro de AstrobiologíaCSIC‐INTAMadridSpain
| | - D.A. Vaz
- Centre for Earth and Space Research of the University of CoimbraObservatório Geofísico e Astronómico da Universidade de CoimbraCoimbraPortugal
| | | | - D. Tirsch
- German Aerospace Center (DLR)Institute of Planetary ResearchBerlinGermany
| | - C.I. Popa
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
| | - M. Pajola
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di PadovaPadovaItaly
| | - G. Franzese
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
| | - G. Mongelluzzo
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
- Department of Industrial EngineeringUniversità di Napoli “Federico II”NapoliItaly
| | - A.C. Ruggeri
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
| | - F. Cozzolino
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
| | - C. Porto
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
| | - F. Esposito
- Istituto Nazionale di Astrofisica (INAF)Osservatorio Astronomico di CapodimonteNapoliItaly
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Chen S, Huang C, Kuo Y, Tseng Y, Gu Y, Earl K, Chen C, Choi Y, Liou K. Impacts of Saharan Mineral Dust on Air-Sea Interaction over North Atlantic Ocean Using a Fully Coupled Regional Model. J Geophys Res Atmos 2021; 126:e2020JD033586. [PMID: 33816041 PMCID: PMC8008257 DOI: 10.1029/2020jd033586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 12/05/2020] [Accepted: 01/10/2021] [Indexed: 06/12/2023]
Abstract
This study examines the modifications of air-sea coupling processes by dust-radiation-cloud interactions over the North Atlantic Ocean using a high-resolution coupled atmosphere-wave-ocean-dust (AWOD) regional model. The dust-induced mechanisms that are responsible for changes of sea surface temperature (SST) and latent and sensible heat fluxes (LHF/SHF) are also examined. Two 3-month numerical experiments are conducted, and they differ only in the activation and deactivation of dust-radiation-cloud interactions. Model results show that the dust significantly reduces surface downward radiation fluxes (SDRF) over the ocean with the maximum change of 20-30 W m-2. Over the dust plume region, the dust effect creates a low-pressure anomaly and a cyclonic circulation anomaly, which drives a positive wind stress curl anomaly, thereby reducing sea surface height and mixed layer depth. However, the SST change by dust, ranging from -0.5 to 0.5 K, has a great spatial variation which differs from the dust plume shape. Dust cools SST around the West African coast, except under the maximum dust plume ridge, and extends westward asymmetrically along the northern and southern edges of the dust plume. Dust unexpectedly warms SST over a large area of the western tropical North Atlantic and north of the dust plume. These SST changes are controlled by different mechanisms. Unlike the SST change pattern, the LHF and SHF changes are mostly reduced underneath the dust plume region, though they are different in detail due to different dominant factors, and increased south of the dust plume over the tropic.
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Affiliation(s)
- Shu‐Hua Chen
- Department of Land, Air, and Water ResourcesUniversity of CaliforniaDavisCAUSA
| | - Chu‐Chun Huang
- Department of Land, Air, and Water ResourcesUniversity of CaliforniaDavisCAUSA
| | - Yi‐Chun Kuo
- Institute of OceanographyNational Taiwan UniversityTaipeiTaiwan
| | - Yu‐Heng Tseng
- Institute of OceanographyNational Taiwan UniversityTaipeiTaiwan
| | - Yu Gu
- Joint Institute for Regional Earth System Science and Engineering and Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Kenneth Earl
- Department of Land, Air, and Water ResourcesUniversity of CaliforniaDavisCAUSA
| | - Chih‐Ying Chen
- Department of Land, Air, and Water ResourcesUniversity of CaliforniaDavisCAUSA
- Research Center for Environmental ChangesAcademia SinicaTaipeiTaiwan
| | - Yonghan Choi
- Department of Land, Air, and Water ResourcesUniversity of CaliforniaDavisCAUSA
- Korea Polar Research InstituteIncheonSouth Korea
| | - Kuo‐Nan Liou
- Joint Institute for Regional Earth System Science and Engineering and Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
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24
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Song EY, Jiménez EI, Lin H, Le Vay K, Krishnamurthy R, Mutschler H. Prebiotically Plausible RNA Activation Compatible with Ribozyme-Catalyzed Ligation. Angew Chem Int Ed Engl 2021; 60:2952-2957. [PMID: 33128282 PMCID: PMC7898671 DOI: 10.1002/anie.202010918] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 10/29/2020] [Indexed: 01/04/2023]
Abstract
RNA-catalyzed RNA ligation is widely believed to be a key reaction for primordial biology. However, since typical chemical routes towards activating RNA substrates are incompatible with ribozyme catalysis, it remains unclear how prebiotic systems generated and sustained pools of activated building blocks needed to form increasingly larger and complex RNA. Herein, we demonstrate in situ activation of RNA substrates under reaction conditions amenable to catalysis by the hairpin ribozyme. We found that diamidophosphate (DAP) and imidazole drive the formation of 2',3'-cyclic phosphate RNA mono- and oligonucleotides from monophosphorylated precursors in frozen water-ice. This long-lived activation enables iterative enzymatic assembly of long RNAs. Our results provide a plausible scenario for the generation of higher-energy substrates required to fuel ribozyme-catalyzed RNA synthesis in the absence of a highly evolved metabolism.
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Affiliation(s)
- Emilie Yeonwha Song
- Max Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | - Eddy Ivanhoe Jiménez
- Department of ChemistryThe Scripps Research Institute10550 North Torrey Pines RoadLa JollaCA92037USA
| | - Huacan Lin
- Department of ChemistryThe Scripps Research Institute10550 North Torrey Pines RoadLa JollaCA92037USA
| | - Kristian Le Vay
- Max Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
| | | | - Hannes Mutschler
- Max Planck Institute of BiochemistryAm Klopferspitz 1882152MartinsriedGermany
- Technical University DortmundOtto-Hahn-Strasse 4a44227DortmundGermany
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25
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Hrycik AR, Stockwell JD. Under-ice mesocosms reveal the primacy of light but the importance of zooplankton in winter phytoplankton dynamics. Limnol Oceanogr 2021; 66:481-495. [PMID: 33776144 PMCID: PMC7984078 DOI: 10.1002/lno.11618] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 07/25/2020] [Accepted: 09/07/2020] [Indexed: 06/12/2023]
Abstract
Factors that regulate planktonic communities under lake ice may be vastly different from those during the open-water season. Expected changes in light availability, ice cover, and snowfall associated with climate change have accelerated the need to understand food web processes under ice. We hypothesized that light limitation (bottom-up control) outweighs zooplankton grazing (top-down control) influence on phytoplankton biovolume and community structure under ice in a north temperate lake. Using in situ under-ice mesocosm experiments, we found that light had stronger effects on phytoplankton abundance than zooplankton, as expected. Specifically, low light limited growth of diatoms, cryptophytes, and chrysophytes. Zooplankton, however, also significantly affected some individual phytoplankton groups by decreasing diatoms and cryptophytes, in contrast to the common assumption that zooplankton grazing has negligible effects under ice. Ammonium and soluble reactive phosphorus (SRP) were lowest in high light treatments presumably through uptake by phytoplankton, whereas ammonium and SRP were highest in high zooplankton treatments, likely a result of zooplankton excretion. In situ experimental studies are commonly applied to understand food web dynamics in open-water conditions, but are extremely rare under ice. Our results suggest that changes in the light environment under ice have significant, rapid effects on phytoplankton growth and community structure and that zooplankton may play a more active role in winter food webs than previously thought. Changes in snow and ice dynamics associated with climate change may alter the light environment in ice-covered systems and significantly influence community structure.
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Affiliation(s)
- Allison R. Hrycik
- Rubenstein Ecosystem Science LaboratoryUniversity of VermontBurlingtonVermontUSA
- Biology DepartmentUniversity of VermontBurlingtonVermontUSA
| | - Jason D. Stockwell
- Rubenstein Ecosystem Science LaboratoryUniversity of VermontBurlingtonVermontUSA
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26
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Nittler LR, Alexander CMO, Patzer A, Verdier‐Paoletti MJ. Presolar stardust in highly pristine CM chondrites Asuka 12169 and Asuka 12236. Meteorit Planet Sci 2021; 56:260-276. [PMID: 33888973 PMCID: PMC8049057 DOI: 10.1111/maps.13618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/01/2020] [Accepted: 12/03/2020] [Indexed: 06/12/2023]
Abstract
We report a NanoSIMS search for presolar grains in the CM chondrites Asuka (A) 12169 and A12236. We found 90 presolar O-rich grains and 25 SiC grains in A12169, giving matrix-normalized abundances of 275 (+55/-50, 1σ) ppm or, excluding an unusually large grain, 236 (+37/-34) ppm for O-rich grains and 62 (+15/-12) ppm for SiC grains. For A12236, 18 presolar silicates and 6 SiCs indicate abundances of 58 (+18/-12) and 20 (+12/-8) ppm, respectively. The SiC abundances are in the typical range of primitive chondrites. The abundance of presolar O-rich grains in A12169 is essentially identical to that in CO3.0 Dominion Range 08006, higher than in any other chondrites, while in A12236, it is higher than found in other CMs. These abundances provide further strong support that A12169 and A12236 are the least-altered CMs as indicated by petrographic investigations. The similar abundances, isotopic distributions, silicate/oxide ratios, and grain sizes of the presolar O-rich grains found here to those of presolar grains in highly primitive CO, CR, and ungrouped carbonaceous chondrites (CCs) indicate that the CM parent body(ies) accreted a similar population of presolar oxides and silicates in their matrices to those accreted by the parent bodies of the other CC groups. The lower abundances and larger grain sizes seen in some other CMs are thus most likely a result of parent-body alteration and not heterogeneity in nebular precursors. Presolar silicates are unlikely to be present in high abundances in returned samples from asteroids Ryugu and Bennu since remote-sensing data indicate that they have experienced substantial aqueous alteration.
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Affiliation(s)
- Larry R. Nittler
- Earth and Planets LaboratoryCarnegie Institution of Washington5241 Broad Branch Rd NWWashingtonDistrict of Columbia20015USA
| | - Conel M. O’D. Alexander
- Earth and Planets LaboratoryCarnegie Institution of Washington5241 Broad Branch Rd NWWashingtonDistrict of Columbia20015USA
| | - Andrea Patzer
- Earth and Planets LaboratoryCarnegie Institution of Washington5241 Broad Branch Rd NWWashingtonDistrict of Columbia20015USA
- Geosciences Center GöttingenUniversity of GöttingenGoldschmidtstr. 137077GöttingenGermany
| | - Maximilien J. Verdier‐Paoletti
- Earth and Planets LaboratoryCarnegie Institution of Washington5241 Broad Branch Rd NWWashingtonDistrict of Columbia20015USA
- Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie (IMPMC)Sorbonne UniversitéMuséum national d’Histoire naturelleUPMC Université Paris 06UMR CNRS 7590IRDUMR 20675005ParisFrance
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27
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Donaldson Hanna KL, Bowles NE, Warren TJ, Hamilton VE, Schrader DL, McCoy TJ, Temple J, Clack A, Calcutt S, Lauretta DS. Spectral Characterization of Bennu Analogs Using PASCALE: A New Experimental Set-Up for Simulating the Near-Surface Conditions of Airless Bodies. J Geophys Res Planets 2021; 126:e2020JE006624. [PMID: 33777607 PMCID: PMC7988566 DOI: 10.1029/2020je006624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/24/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
We describe the capabilities, radiometric stability, and calibration of a custom vacuum environment chamber capable of simulating the near-surface conditions of airless bodies. Here we demonstrate the collection of spectral measurements of a suite of fine particulate asteroid analogs made using the Planetary Analogue Surface Chamber for Asteroid and Lunar Environments (PASCALE) under conditions like those found on Earth and on airless bodies. The sample suite includes anhydrous and hydrated physical mixtures, and chondritic meteorites (CM, CI, CV, CR, and L5) previously characterized under Earth- and asteroid-like conditions. And for the first time, we measure the terrestrial and extra-terrestrial mineral end members used in the olivine- and phyllosilicate-dominated physical mixtures under the same conditions as the mixtures and meteorites allowing us better understand how minerals combine spectrally when mixed intimately. Our measurements highlight the sensitivity of thermal infrared emissivity spectra to small amounts of low albedo materials and the composition of the sample materials. As the albedo of the sample decreases, we observe smaller differences between Earth- and asteroid-like spectra, which results from a reduced thermal gradient in the upper hundreds of microns in the sample. These spectral measurements can be compared to thermal infrared emissivity spectra of asteroid (101955) Bennu's surface in regions where similarly fine particulate materials may be observed to infer surface compositions.
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Affiliation(s)
- K. L. Donaldson Hanna
- Department of PhysicsUniversity of Central FloridaOrlandoFLUSA
- Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxfordUK
| | - N. E. Bowles
- Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxfordUK
| | - T. J. Warren
- Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxfordUK
| | - V. E. Hamilton
- Department of Space ScienceSouthwest Research InstituteBoulderCOUSA
| | - D. L. Schrader
- Center for Meteorite StudiesArizona State UniversityTempeAZUSA
| | - T. J. McCoy
- Smithsonian National Museum of Natural HistoryWashingtonD CUSA
| | - J. Temple
- Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxfordUK
| | - A. Clack
- Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxfordUK
| | - S. Calcutt
- Atmospheric Oceanic and Planetary PhysicsUniversity of OxfordOxfordUK
| | - D. S. Lauretta
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
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28
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Kass JM, Meenan SI, Tinoco N, Burneo SF, Anderson RP. Improving area of occupancy estimates for parapatric species using distribution models and support vector machines. Ecol Appl 2021; 31:e02228. [PMID: 32970879 PMCID: PMC7816235 DOI: 10.1002/eap.2228] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 05/11/2020] [Accepted: 07/13/2020] [Indexed: 06/11/2023]
Abstract
As geographic range estimates for the IUCN Red List guide conservation actions, accuracy and ecological realism are crucial. IUCN's extent of occurrence (EOO) is the general region including the species' range, while area of occupancy (AOO) is the subset of EOO occupied by the species. Data-poor species with incomplete sampling present particular difficulties, but species distribution models (SDMs) can be used to predict suitable areas. Nevertheless, SDMs typically employ abiotic variables (i.e., climate) and do not explicitly account for biotic interactions that can impose range constraints. We sought to improve range estimates for data-poor, parapatric species by masking out areas under inferred competitive exclusion. We did so for two South American spiny pocket mice: Heteromys australis (Least Concern) and Heteromys teleus (Vulnerable due to especially poor sampling), whose ranges appear restricted by competition. For both species, we estimated EOO using SDMs and AOO with four approaches: occupied grid cells, abiotic SDM prediction, and this prediction masked by approximations of the areas occupied by each species' congener. We made the masks using support vector machines (SVMs) fit with two data types: occurrence coordinates alone; and coordinates along with SDM predictions of suitability. Given the uncertainty in calculating AOO for low-data species, we made estimates for the lower and upper bounds for AOO, but only make recommendations for H. teleus as its full known range was considered. The SVM approaches (especially the second one) had lower classification error and made more ecologically realistic delineations of the contact zone. For H. teleus, the lower AOO bound (a strongly biased underestimate) corresponded to Endangered (occupied grid cells), while the upper bounds (other approaches) led to Near Threatened. As we currently lack data to determine the species' true occupancy within the post-processed SDM prediction, we recommend that an updated listing for H. teleus include these bounds for AOO. This study advances methods for estimating the upper bound of AOO and highlights the need for better ways to produce unbiased estimates of lower bounds. More generally, the SVM approaches for post-processing SDM predictions hold promise for improving range estimates for other uses in biogeography and conservation.
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Affiliation(s)
- Jamie M. Kass
- Ph.D. Program in BiologyThe Graduate CenterCUNYNew YorkNew York10016USA
- Department of BiologyCity College of New York (CUNY)New YorkNew York10031USA
- Biodiversity and Biocomplexity UnitOkinawa Institute of Science and Technology Graduate UniversityTancha, Onna‐son, Kunigami‐gunOkinawa904‐0495Japan
| | - Sarah I. Meenan
- Department of BiologyCity College of New York (CUNY)New YorkNew York10031USA
| | - Nicolás Tinoco
- Museo de ZoologíaPontificia Universidad Católica del EcuadorAvenida 12 de Octubre, 1076 y Roca170517QuitoEcuador
| | - Santiago F. Burneo
- Museo de ZoologíaPontificia Universidad Católica del EcuadorAvenida 12 de Octubre, 1076 y Roca170517QuitoEcuador
| | - Robert P. Anderson
- Ph.D. Program in BiologyThe Graduate CenterCUNYNew YorkNew York10016USA
- Department of BiologyCity College of New York (CUNY)New YorkNew York10031USA
- Division of Vertebrate Zoology (Mammalogy)American Museum of Natural HistoryNew YorkNew York10024USA
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29
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Kraatz S, Rose S, Cosh M, Torbick N, Huang X, Siqueira P. Performance Evaluation of UAVSAR and Simulated NISAR Data for Crop/Noncrop Classification Over Stoneville, MS. Earth Space Sci 2021; 8:e2020EA001363. [PMID: 33681415 PMCID: PMC7900998 DOI: 10.1029/2020ea001363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 10/26/2020] [Accepted: 11/12/2020] [Indexed: 06/12/2023]
Abstract
Synthetic Aperture Radar (SAR) data are well-suited for change detection over agricultural fields, owing to high spatiotemporal resolution and sensitivity to soil and vegetation. The goal of this work is to evaluate the science algorithm for the NASA ISRO SAR (NISAR) Cropland Area product using data collected by NASA's airborne Uninhabited Aerial Vehicle SAR (UAVSAR) platform and the simulated NISAR data derived from it. This study uses mode 129, which is to be used for global-scale mapping. The mode consists of an upper (129A) and lower band (129B), respectively having bandwidths of 20 and 5 MHz. This work uses 129A data because it has a four times finer range resolution compared to 129B. The NISAR algorithm uses the coefficient of variation (CV) to perform crop/noncrop classification at 100 m. We evaluate classifications using three accuracy metrics (overall accuracy, J-statistic, Cohen's Kappa) and spatial resolutions (10, 30, and 100 m) for crop/noncrop delineating CV thresholds (CVthr) ranging from 0 to 1 in 0.01 increments. All but the 10 m 129A product exceeded NISAR's mission accuracy requirement of 80%. The UAVSAR 10 m data performed best, achieving maximum overall accuracy, J-statistic, and Kappa values of 85%, 0.62, and 0.60. The same metrics for the 129A product respectively are: 77%, 0.40, 0.36 at 10 m; 81%, 0.55, 0.49 at 30 m; 80%, 0.58, 0.50 at 100 m. We found that using a literature recommended CVthr value of 0.5 yielded suboptimal accuracy (65%) at this site and that optimal CVthr values monotonically decreased with decreasing spatial resolution.
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Affiliation(s)
- S. Kraatz
- Department of Electrical and Computer EngineeringUniversity of MassachusettsAmherstMAUSA
| | - S. Rose
- Department of Electrical and Computer EngineeringUniversity of MassachusettsAmherstMAUSA
| | - M.H. Cosh
- USDA ARS Hydrology and Remote Sensing LaboratoryBeltsvilleMDUSA
| | | | | | - P. Siqueira
- Department of Electrical and Computer EngineeringUniversity of MassachusettsAmherstMAUSA
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30
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Fer I, Gardella AK, Shiklomanov AN, Campbell EE, Cowdery EM, De Kauwe MG, Desai A, Duveneck MJ, Fisher JB, Haynes KD, Hoffman FM, Johnston MR, Kooper R, LeBauer DS, Mantooth J, Parton WJ, Poulter B, Quaife T, Raiho A, Schaefer K, Serbin SP, Simkins J, Wilcox KR, Viskari T, Dietze MC. Beyond ecosystem modeling: A roadmap to community cyberinfrastructure for ecological data-model integration. Glob Chang Biol 2021; 27:13-26. [PMID: 33075199 PMCID: PMC7756391 DOI: 10.1111/gcb.15409] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 09/16/2020] [Indexed: 05/10/2023]
Abstract
In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to fully exploit the growing volume and variety of available data. Here, we take a critical look at the information infrastructure that connects ecosystem modeling and measurement efforts, and propose a roadmap to community cyberinfrastructure development that can reduce the divisions between empirical research and modeling and accelerate the pace of discovery. A new era of data-model integration requires investment in accessible, scalable, and transparent tools that integrate the expertise of the whole community, including both modelers and empiricists. This roadmap focuses on five key opportunities for community tools: the underlying foundations of community cyberinfrastructure; data ingest; calibration of models to data; model-data benchmarking; and data assimilation and ecological forecasting. This community-driven approach is a key to meeting the pressing needs of science and society in the 21st century.
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Affiliation(s)
- Istem Fer
- Finnish Meteorological InstituteHelsinkiFinland
| | - Anthony K. Gardella
- Department of Earth and EnvironmentBoston UniversityBostonMAUSA
- School for Environment and SustainabilityUniversity of MichiganAnn ArborMIUSA
| | | | | | | | - Martin G. De Kauwe
- ARC Centre of Excellence for Climate ExtremesSydneyNSWAustralia
- Climate Change Research CentreUniversity of New South WalesSydneyNSWAustralia
- Evolution & Ecology Research CentreUniversity of New South WalesSydneyNSWAustralia
| | - Ankur Desai
- Department of Atmospheric and Oceanic SciencesUniversity of Wisconsin‐MadisonMadisonWIUSA
| | | | - Joshua B. Fisher
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - Forrest M. Hoffman
- Computational Earth Sciences Group and Climate Change Science InstituteOak Ridge National LaboratoryOak RidgeTNUSA
- Department of Civil and Environmental EngineeringUniversity of TennesseeKnoxvilleTNUSA
| | - Miriam R. Johnston
- Department of Organismic and Evolutionary BiologyHarvard UniversityCambridgeMAUSA
| | - Rob Kooper
- NCSA (National Center for Supercomputing Applications)University of Illinois at Urbana ChampaignUrbanaILUSA
| | - David S. LeBauer
- College of Agriculture and Life SciencesUniversity of ArizonaTucsonAZUSA
| | | | - William J. Parton
- Natural Resource Ecology LaboratoryColorado State UniversityFort CollinsCOUSA
| | - Benjamin Poulter
- Biospheric Sciences Laboratory (618)NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Tristan Quaife
- UK National Centre for Earth Observation and Department of MeteorologyUniversity of ReadingReadingUK
| | - Ann Raiho
- Fish, Wildlife, and Conservation Biology DepartmentColorado State UniversityFort CollinsCOUSA
| | - Kevin Schaefer
- National Snow and Ice Data CenterCooperative Institute for Research in Environmental SciencesUniversity of ColoradoBoulderCOUSA
| | - Shawn P. Serbin
- Brookhaven National LaboratoryEnvironmental and Climate Sciences DepartmentUptonNYUSA
| | | | - Kevin R. Wilcox
- Ecosystem Science and ManagementUniversity of WyomingLaramieWYUSA
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31
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Werner F, Schwartz MJ, Livesey NJ, Read WG, Santee ML. Extreme Outliers in Lower Stratospheric Water Vapor Over North America Observed by MLS: Relation to Overshooting Convection Diagnosed From Colocated Aqua-MODIS Data. Geophys Res Lett 2020; 47:e2020GL090131. [PMID: 33518832 PMCID: PMC7816234 DOI: 10.1029/2020gl090131] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/29/2020] [Accepted: 11/12/2020] [Indexed: 05/21/2023]
Abstract
Convectively injected water vapor (H2O) in the North American (NA) summer lowermost stratosphere results in significant outliers in the 100-hPa H2O measurements from the Aura Microwave Limb Sounder (MLS). MLS statistics from 15 years confirm that the NA region contains over 60% of global 100-hPa H2O > 12 ppmv, despite having only ∼1.8% of all MLS observations. A profile sampled in August 2019 stands out, withH 2 O = 26 . 3 ppmv, far exceeding the prior record and the median ∼4.5-ppmv abundance in NA. This particular outlier is associated with a large overshooting convective event (OCE) that spanned multiple U.S. states and persisted for several hours. Colocation of the MLS data over NA with cloud observations from Aqua's Moderate Resolution Imaging Spectroradiometer (MODIS) reveals the unique character of this case, as only 2.3% of MLS profiles are as close to an OCE and only 0.024% of OCEs cover as large an area within a 500-km perimeter of a profile.
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Affiliation(s)
- F. Werner
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - M. J. Schwartz
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - N. J. Livesey
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - W. G. Read
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - M. L. Santee
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
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32
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Sherman J, Gorbunov MY, Schofield O, Falkowski PG. Photosynthetic energy conversion efficiency in the West Antarctic Peninsula. Limnol Oceanogr 2020; 65:2912-2925. [PMID: 33380749 PMCID: PMC7754432 DOI: 10.1002/lno.11562] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 04/18/2020] [Accepted: 06/23/2020] [Indexed: 06/12/2023]
Abstract
The West Antarctic Peninsula (WAP) is a highly productive polar ecosystem where phytoplankton dynamics are regulated by intense bottom-up control from light and iron availability. Rapid climate change along the WAP is driving shifts in the mixed layer depth and iron availability. Elucidating the relative role of each of these controls and their interactions is crucial for understanding of how primary productivity will change in coming decades. Using a combination of ultra-high-resolution variable chlorophyll fluorescence together with fluorescence lifetime analyses on the 2017 Palmer Long Term Ecological Research cruise, we mapped the temporal and spatial variability in phytoplankton photophysiology across the WAP. Highest photosynthetic energy conversion efficiencies and lowest fluorescence quantum yields were observed in iron replete coastal regions. Photosynthetic energy conversion efficiencies decreased by ~ 60% with a proportional increase in quantum yields of thermal dissipation and fluorescence on the outer continental shelf and slope. The combined analysis of variable fluorescence and lifetimes revealed that, in addition to the decrease in the fraction of inactive reaction centers, up to 20% of light harvesting chlorophyll-protein antenna complexes were energetically uncoupled from photosystem II reaction centers in iron-limited phytoplankton. These biophysical signatures strongly suggest severe iron limitation of photosynthesis in the surface waters along the continental slope of the WAP.
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Affiliation(s)
- Jonathan Sherman
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, RutgersThe State University of New JerseyNew BrunswickNew JerseyUSA
| | - Maxim Y. Gorbunov
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, RutgersThe State University of New JerseyNew BrunswickNew JerseyUSA
| | - Oscar Schofield
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, RutgersThe State University of New JerseyNew BrunswickNew JerseyUSA
- Center for Ocean Observing Leadership, Department of Marine and Coastal SciencesRutgers, The State University of New JerseyNew BrunswickNew JerseyUSA
| | - Paul G. Falkowski
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, RutgersThe State University of New JerseyNew BrunswickNew JerseyUSA
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33
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Jacob SR, Wellington DF, Bell JF, Achilles C, Fraeman AA, Horgan B, Johnson JR, Maurice S, Peters GH, Rampe EB, Thompson LM, Wiens RC. Spectral, Compositional, and Physical Properties of the Upper Murray Formation and Vera Rubin Ridge, Gale Crater, Mars. J Geophys Res Planets 2020; 125:e2019JE006290. [PMID: 33282613 PMCID: PMC7685153 DOI: 10.1029/2019je006290] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 05/20/2023]
Abstract
During 2018 and 2019, the Mars Science Laboratory Curiosity rover investigated the chemistry, morphology, and stratigraphy of Vera Rubin ridge (VRR). Using orbital data from the Compact Reconnaissance Imaging Spectrometer for Mars, scientists attributed the strong 860 nm signal associated with VRR to the presence of red crystalline hematite. However, Mastcam multispectral data and CheMin X-ray diffraction (XRD) measurements show that the depth of the 860 nm absorption is negatively correlated with the abundance of red crystalline hematite, suggesting that other mineralogical or physical parameters are also controlling the 860 nm absorption. Here, we examine Mastcam and ChemCam passive reflectance spectra from VRR and other locations to link the depth, position, and presence or absence of iron-related mineralogic absorption features to the XRD-derived rock mineralogy. Correlating CheMin mineralogy to spectral parameters showed that the ~860 nm absorption has a strong positive correlation with the abundance of ferric phyllosilicates. New laboratory reflectance measurements of powdered mineral mixtures can reproduce trends found in Gale crater. We hypothesize that variations in the 860 nm absorption feature in Mastcam and ChemCam observations of VRR materials are a result of three factors: (1) variations in ferric phyllosilicate abundance due to its ~800-1,000 nm absorption; (2) variations in clinopyroxene abundance because of its band maximum at ~860 nm; and (3) the presence of red crystalline hematite because of its absorption centered at 860 nm. We also show that relatively small changes in Ca-sulfate abundance is one potential cause of the erosional resistance and geomorphic expression of VRR.
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Affiliation(s)
- S. R. Jacob
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
| | - D. F. Wellington
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
| | - J. F. Bell
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
| | - C. Achilles
- NASA Goddard Space Flight CenterGreenbeltMDUSA
| | - A. A. Fraeman
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - B. Horgan
- Department of Earth, Atmospheric, and Planetary SciencesPurdue UniversityWest LafayetteINUSA
| | - J. R. Johnson
- Johns Hopkins University Applied Physics LaboratoryLaurelMDUSA
| | - S. Maurice
- Institut de Recherche en Astrophysique et PlanetologieToulouseFrance
| | - G. H. Peters
- NASA Neil A. Armstrong Flight Research CenterEdwardsCAUSA
| | | | - L. M. Thompson
- Planetary and Space Science CentreUniversity of New BrunswickCanada
| | - R. C. Wiens
- Los Alamos National LaboratoryLos AlamosNMUSA
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34
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Heck PR, Greer J, Boesenberg JS, Bouvier A, Caffee MW, Cassata WS, Corrigan C, Davis AM, Davis DW, Fries M, Hankey M, Jenniskens P, Schmitt‐Kopplin P, Sheu S, Trappitsch R, Velbel M, Weller B, Welten K, Yin Q, Sanborn ME, Ziegler K, Rowland D, Verosub KL, Zhou Q, Liu Y, Tang G, Li Q, Li X, Zajacz Z. The fall, recovery, classification, and initial characterization of the Hamburg, Michigan H4 chondrite. Meteorit Planet Sci 2020; 55:2341-2359. [PMID: 33510569 PMCID: PMC7820957 DOI: 10.1111/maps.13584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 07/30/2020] [Accepted: 09/23/2020] [Indexed: 06/12/2023]
Abstract
The Hamburg meteorite fell on January 16, 2018, near Hamburg, Michigan, after a fireball event widely observed in the U.S. Midwest and in Ontario, Canada. Several fragments fell onto frozen surfaces of lakes and, thanks to weather radar data, were recovered days after the fall. The studied rock fragments show no or little signs of terrestrial weathering. Here, we present the initial results from an international consortium study to describe the fall, characterize the meteorite, and probe the collision history of Hamburg. About 1 kg of recovered meteorites was initially reported. Petrology, mineral chemistry, trace element and organic chemistry, and O and Cr isotopic compositions are characteristic of H4 chondrites. Cosmic ray exposure ages based on cosmogenic 3He, 21Ne, and 38Ar are ~12 Ma, and roughly agree with each other. Noble gas data as well as the cosmogenic 10Be concentration point to a small 40-60 cm diameter meteoroid. An 40Ar-39Ar age of 4532 ± 24 Ma indicates no major impact event occurring later in its evolutionary history, consistent with data of other H4 chondrites. Microanalyses of phosphates with LA-ICPMS give an average Pb-Pb age of 4549 ± 36 Ma. This is in good agreement with the average SIMS Pb-Pb phosphate age of 4535.3 ± 9.5 Ma and U-Pb Concordia age of 4535 ± 10 Ma. The weighted average age of 4541.6 ± 9.5 Ma reflects the metamorphic phosphate crystallization age after parent body formation in the early solar system.
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35
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Horgan BHN, Johnson JR, Fraeman AA, Rice MS, Seeger C, Bell JF, Bennett KA, Cloutis EA, Edgar LA, Frydenvang J, Grotzinger JP, L'Haridon J, Jacob SR, Mangold N, Rampe EB, Rivera‐Hernandez F, Sun VZ, Thompson LM, Wellington D. Diagenesis of Vera Rubin Ridge, Gale Crater, Mars, From Mastcam Multispectral Images. J Geophys Res Planets 2020; 125:e2019JE006322. [PMID: 33282614 PMCID: PMC7685111 DOI: 10.1029/2019je006322] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 09/03/2020] [Accepted: 09/19/2020] [Indexed: 05/13/2023]
Abstract
Images from the Mars Science Laboratory (MSL) mission of lacustrine sedimentary rocks of Vera Rubin ridge on "Mt. Sharp" in Gale crater, Mars, have shown stark color variations from red to purple to gray. These color differences crosscut stratigraphy and are likely due to diagenetic alteration of the sediments after deposition. However, the chemistry and timing of these fluid interactions is unclear. Determining how diagenetic processes may have modified chemical and mineralogical signatures of ancient Martian environments is critical for understanding the past habitability of Mars and achieving the goals of the MSL mission. Here we use visible/near-infrared spectra from Mastcam and ChemCam to determine the mineralogical origins of color variations in the ridge. Color variations are consistent with changes in spectral properties related to the crystallinity, grain size, and texture of hematite. Coarse-grained gray hematite spectrally dominates in the gray patches and is present in the purple areas, while nanophase and fine-grained red crystalline hematite are present and spectrally dominate in the red and purple areas. We hypothesize that these differences were caused by grain-size coarsening of hematite by diagenetic fluids, as observed in terrestrial analogs. In this model, early primary reddening by oxidizing fluids near the surface was followed during or after burial by bleaching to form the gray patches, possibly with limited secondary reddening after exhumation. Diagenetic alteration may have diminished the preservation of biosignatures and changed the composition of the sediments, making it more difficult to interpret how conditions evolved in the paleolake over time.
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Affiliation(s)
- Briony H. N. Horgan
- Department of Earth, Atmospheric, and Planetary SciencesPurdue UniversityWest LafayetteINUSA
| | | | - Abigail A. Fraeman
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Melissa S. Rice
- Geology Department, Physics and Astronomy DepartmentWestern Washington UniversityBellinghamWAUSA
| | - Christina Seeger
- Geology Department, Physics and Astronomy DepartmentWestern Washington UniversityBellinghamWAUSA
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - James F. Bell
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
| | | | | | - Lauren A. Edgar
- U.S. Geological SurveyAstrogeology Science CenterFlagstaffAZ
| | | | - John P. Grotzinger
- Division of Geological and Planetary SciencesCalifornia Institute of TechnologyPasadenaCAUSA
| | - Jonas L'Haridon
- Laboratoire de Planétologie et GéodynamiqueCNRS, Univ Nantes, Univ AngersNantesFrance
| | - Samantha R. Jacob
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
| | - Nicolas Mangold
- Laboratoire de Planétologie et GéodynamiqueCNRS, Univ Nantes, Univ AngersNantesFrance
| | | | | | - Vivian Z. Sun
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - Lucy M. Thompson
- Planetary and Space Science CentreUniversity of New BrunswickFrederictonNew BrunswickCanada
| | - Danika Wellington
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
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36
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Medina Ferrer F, Hobart K, Bailey JV. Field detection of urease and carbonic anhydrase activity using rapid and economical tests to assess microbially induced carbonate precipitation. Microb Biotechnol 2020; 13:1877-1888. [PMID: 32720477 PMCID: PMC7533345 DOI: 10.1111/1751-7915.13630] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/26/2020] [Indexed: 01/01/2023] Open
Abstract
Microbial precipitation of calcium carbonate is a widespread environmental phenomenon that has diverse engineering applications, from building and soil restoration to carbon sequestration. Urease-mediated ureolysis and CO2 (de)hydration by carbonic anhydrase (CA) are known for their potential to precipitate carbonate minerals, yet many environmental microbial community studies rely on marker gene or metagenomic approaches that are unable to determine in situ activity. Here, we developed fast and cost-effective tests for the field detection of urease and CA activity using pH-sensitive strips inside microcentrifuge tubes that change colour in response to the reaction products of urease (NH3 ) and CA (CO2 ). The urease assay proved sensitive and useful in the field to detect in situ activity in biofilms from a saline lake, a series of calcareous fens, and ferrous springs, finding relatively high urease activity in lake samples. Incubations of lake microbes with urea resulted in significantly higher CaCO3 precipitation compared to incubations with a urease inhibitor, showing that the rapid assay indicated an on-site active metabolism potentially mediating carbonate precipitation. The CA assay, however, showed less sensitivity compared to the urease test. While its sensitivity limits its utility, the assay may still be useful as a preliminary indicator given the paucity of other means for detecting CA activity in the field. Field urease, and potentially CA, activity assays complement molecular approaches and facilitate the search for carbonate-precipitating microbes and their in situ activity, which could be applied toward agriculture, engineering and carbon sequestration technologies.
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Affiliation(s)
- Fernando Medina Ferrer
- Department of Earth & Environmental SciencesCollege of Science & EngineeringUniversity of Minnesota, Twin CitiesMinneapolisMNUSA
| | - Kathryn Hobart
- Department of Earth & Environmental SciencesCollege of Science & EngineeringUniversity of Minnesota, Twin CitiesMinneapolisMNUSA
- Institute for Rock MagnetismUniversity of Minnesota, Twin CitiesMinneapolisMNUSA
| | - Jake V. Bailey
- Department of Earth & Environmental SciencesCollege of Science & EngineeringUniversity of Minnesota, Twin CitiesMinneapolisMNUSA
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37
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Aponte JC, Elsila JE, Hein JE, Dworkin JP, Glavin DP, McLain HL, Parker ET, Cao T, Berger EL, Burton AS. Analysis of amino acids, hydroxy acids, and amines in CR chondrites. Meteorit Planet Sci 2020; 55:2422-2439. [PMID: 33536738 PMCID: PMC7839561 DOI: 10.1111/maps.13586] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 09/23/2020] [Indexed: 05/20/2023]
Abstract
The abundances, relative distributions, and enantiomeric and isotopic compositions of amines, amino acids, and hydroxy acids in Miller Range (MIL) 090001 and MIL 090657 meteorites were determined. Chiral distributions and isotopic compositions confirmed that most of the compounds detected were indigenous to the meteorites and not the result of terrestrial contamination. Combined with data in the literature, suites of these compounds have now been analyzed in a set of six CR chondrites, spanning aqueous alteration types 2.0-2.8. Amino acid abundances ranged from 17 to 3300 nmol g-1 across the six CRs; hydroxy acid abundances ranged from 180 to 1800 nmol g-1; and amine abundances ranged from 40 to 2100 nmol g-1. For amino acids and amines, the weakly altered chondrites contained the highest abundances, whereas hydroxy acids were most abundant in the more altered CR2.0 chondrite. Because water contents in the meteorites are orders of magnitude greater than soluble organics, synthesis of hydroxy acids, which requires water, may be less affected by aqueous alteration than amines and amino acids that require nitrogen-bearing precursors. Two chiral amino acids that were plausibly extraterrestrial in origin were present with slight enantiomeric excesses: L-isovaline (~10% excess) and D-β-amino-n-butyric acid (~9% excess); further studies are needed to verify that the chiral excess in the latter compound is truly extraterrestrial in origin. The isotopic compositions of compounds reported here did not reveal definitive links between the different compound classes such as common synthetic precursors, but will provide a framework for further future in-depth analyses.
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Affiliation(s)
- José C. Aponte
- Department of ChemistryCatholic University of AmericaWashingtonDistrict of Columbia20064USA
- Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltMaryland20771USA
| | - Jamie E. Elsila
- Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltMaryland20771USA
| | - Jason E. Hein
- University of British ColumbiaBritish ColumbiaV6T 1Z2Canada
| | - Jason P. Dworkin
- Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltMaryland20771USA
| | - Daniel P. Glavin
- Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltMaryland20771USA
| | - Hannah L. McLain
- Department of ChemistryCatholic University of AmericaWashingtonDistrict of Columbia20064USA
- Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltMaryland20771USA
| | - Eric T. Parker
- Solar System Exploration DivisionNASA Goddard Space Flight CenterGreenbeltMaryland20771USA
| | - Timothy Cao
- Department of ChemistryUniversity of CaliforniaMercedCalifornia95343USA
| | - Eve L. Berger
- Astromaterials Research and Exploration Science DivisionTexas State University / Jacobs JETS ContractNASA Johnson Space CenterHoustonTexas77058USA
| | - Aaron S. Burton
- Astromaterials Research and Exploration Science DivisionNASA Johnson Space CenterHoustonTexas77058USA
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38
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Zhu Y, Liang X. Coupling of the Surface and Near-Bottom Currents in the Gulf of Mexico. J Geophys Res Oceans 2020; 125:e2020JC016488. [PMID: 33282616 PMCID: PMC7685172 DOI: 10.1029/2020jc016488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 09/17/2020] [Accepted: 10/17/2020] [Indexed: 06/12/2023]
Abstract
Coupling between the surface and near-bottom currents in the Gulf of Mexico (GoM) has been reported in many case studies. However, geographical variations of this coupling need more examination. In this study, surface geostrophic currents derived from satellite-observed sea surface height and subsurface currents from a collection of deep ocean moorings are used to examine the surface and bottom coupling in different parts of the GoM. The short-period (30-90 days) fluctuations generated by the Loop Current (LC) and the LC eddies (LCEs) have a more vertically coherent structure and stronger deep ocean expressions than the long-period fluctuations (>90 days). In addition, the strength of the coupling is modulated by the long-period variations of the LC and LCE sheddings. Moreover, the surface and bottom coupling varies geographically. In the LC region, the surface fluctuations along the eastern side of the LC are important in causing the bottom current fluctuations through baroclinic instability under the LC and through traveling topographic Rossby waves (TRWs) north of the LC. In the central deep GoM, the bottom currents are affected by the upper fluctuations of the northern LC through both local baroclinic instability and remote TRW propagation. In the northwestern GoM, the bottom current fluctuations are largely related to the remote surface variability from the west side of the LC by TRWs propagating northwestward. This study will help us better understand mechanisms of the bottom current fluctuations that are important for the dispersal of deep ocean materials and properties.
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Affiliation(s)
- Yingli Zhu
- School of Marine Science and PolicyUniversity of DelawareNewarkDEUSA
| | - Xinfeng Liang
- School of Marine Science and PolicyUniversity of DelawareNewarkDEUSA
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39
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Gurney KR, Liang J, Patarasuk R, Song Y, Huang J, Roest G. The Vulcan Version 3.0 High-Resolution Fossil Fuel CO 2 Emissions for the United States. J Geophys Res Atmos 2020; 125:e2020JD032974. [PMID: 33133992 PMCID: PMC7583371 DOI: 10.1029/2020jd032974] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 07/15/2020] [Accepted: 08/30/2020] [Indexed: 05/05/2023]
Abstract
Estimates of high-resolution greenhouse gas (GHG) emissions have become a critical component of climate change research and an aid to decision makers considering GHG mitigation opportunities. The "Vulcan Project" is an effort to estimate bottom-up carbon dioxide emissions from fossil fuel combustion and cement production (FFCO2) for the U.S. landscape at space and time scales that satisfy both scientific and policy needs. Here, we report on the Vulcan version 3.0 which quantifies emissions at a resolution of 1 km2/hr for the 2010-2015 time period. We estimate 2011 FFCO2 emissions of 1,589.9 TgC with a 95% confidence interval of 1,367/1,853 TgC (-14.0%/+16.6%), implying a one-sigma uncertainty of ~ ±8%. Per capita emissions are larger in states dominated by electricity production and industrial activity and smaller where onroad and building emissions dominate. The U.S. FFCO2 emissions center of mass (CoM) is located in the state of Missouri with mean seasonality that moves on a near-elliptical NE/SW path. Comparison to ODIAC, a global gridded FFCO2 emissions estimate, shows large total emissions differences (100.4 TgC for year 2011), a spatial correlation of 0.68 (R2), and a mean absolute relative difference at the 1 km2 scale of 104.3%. The Vulcan data product offers a high-resolution estimate of FFCO2 emissions in every U.S. city, obviating costly development of self-reported urban inventories. The Vulcan v3.0 annual gridded emissions data product can be downloaded from the Oak Ridge National Laboratory Distributed Active Archive Center (Gurney, Liang, et al., 2019, https://doi.org/10.3334/ORNLDAAC/1741).
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Affiliation(s)
- Kevin R. Gurney
- School of Informatics, Computing, and Cyber SystemsNorthern Arizona UniversityFlagstaffAZUSA
| | - Jianming Liang
- School of Life SciencesArizona State UniversityTempeAZUSA
- ESRIRedlandsCAUSA
| | - Risa Patarasuk
- School of Life SciencesArizona State UniversityTempeAZUSA
- Citrus County Board of CommissionersLecantoFLUSA
| | - Yang Song
- School of Life SciencesArizona State UniversityTempeAZUSA
| | - Jianhua Huang
- School of Life SciencesArizona State UniversityTempeAZUSA
- VISA ResearchAustinTXUSA
| | - Geoffrey Roest
- School of Informatics, Computing, and Cyber SystemsNorthern Arizona UniversityFlagstaffAZUSA
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40
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Bishop SP, Small RJ, Bryan FO. The Global Sink of Available Potential Energy by Mesoscale Air-Sea Interaction. J Adv Model Earth Syst 2020; 12:e2020MS002118. [PMID: 33282115 PMCID: PMC7685163 DOI: 10.1029/2020ms002118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 07/23/2020] [Accepted: 08/17/2020] [Indexed: 06/12/2023]
Abstract
The thermal component of oceanic eddy available potential energy (EPE) generation due to air-sea interaction is proportional to the product of anomalous sea surface temperature (SST) and net air-sea heat flux (SHF). In this study we assess EPE generation and its timescale and space-scale dependence from observations and a high-resolution coupled climate model. A dichotomy exists in the literature with respect to the sign of this term, that is, whether it is a source or a sink of EPE. We resolve this dichotomy by partitioning the SST and net heat flux into climatological mean, climatological seasonal cycle, and remaining transient contributions, thereby separating the mesoscale eddy variability from the forced seasonal cycle. In this decomposition the mesoscale air-sea SST-SHF feedbacks act as a 0.1 TW global sink of EPE. In regions of the ocean with a large seasonal cycle, for example, midlatitudes of the Northern Hemisphere, the EPE generation by the forced seasonal cycle exceeds the mesoscale variability sink, such that the global generation by seasonal plus eddy variability acts as a 0.8 TW source. EPE destruction is largest in the midlatitude western boundary currents due to mesoscale air-sea interaction and in the tropical Pacific where SST variability is due mainly to the El Niño-Southern Oscillation. The EPE sink in western boundary currents is spatially aligned with SST gradients and offset to the poleward side of currents, while the mean and seasonal generation are aligned with the warm core of the current. By successively smoothing the data in space and time we find that half of the EPE sink is confined to timescales less than annual and length scales less than 2°, within the oceanic mesoscale band.
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Affiliation(s)
- Stuart P. Bishop
- Department of Marine, Earth, & Atmospheric SciencesNorth Carolina State University at RaleighRaleighNCUSA
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Meireles JE, Cavender‐Bares J, Townsend PA, Ustin S, Gamon JA, Schweiger AK, Schaepman ME, Asner GP, Martin RE, Singh A, Schrodt F, Chlus A, O'Meara BC. Leaf reflectance spectra capture the evolutionary history of seed plants. New Phytol 2020; 228:485-493. [PMID: 32579721 PMCID: PMC7540507 DOI: 10.1111/nph.16771] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 06/13/2020] [Indexed: 05/22/2023]
Abstract
Leaf reflectance spectra have been increasingly used to assess plant diversity. However, we do not yet understand how spectra vary across the tree of life or how the evolution of leaf traits affects the differentiation of spectra among species and lineages. Here we describe a framework that integrates spectra with phylogenies and apply it to a global dataset of over 16 000 leaf-level spectra (400-2400 nm) for 544 seed plant species. We test for phylogenetic signal in spectra, evaluate their ability to classify lineages, and characterize their evolutionary dynamics. We show that phylogenetic signal is present in leaf spectra but that the spectral regions most strongly associated with the phylogeny vary among lineages. Despite among-lineage heterogeneity, broad plant groups, orders, and families can be identified from reflectance spectra. Evolutionary models also reveal that different spectral regions evolve at different rates and under different constraint levels, mirroring the evolution of their underlying traits. Leaf spectra capture the phylogenetic history of seed plants and the evolutionary dynamics of leaf chemistry and structure. Consequently, spectra have the potential to provide breakthrough assessments of leaf evolution and plant phylogenetic diversity at global scales.
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Affiliation(s)
- José Eduardo Meireles
- School of Biology and EcologyUniversity of MaineOronoME04469USA
- Department of Ecology, Evolution and BehaviorUniversity of MinnesotaSaint PaulMN55108USA
| | | | - Philip A. Townsend
- Department of Forest and Wildlife EcologyUniversity of Wisconsin–MadisonMadisonWI53706USA
| | - Susan Ustin
- John Muir Institute of the Environment and Department of Land, Air, and Water ResourcesUniversity of CaliforniaDavisCA95616USA
| | - John A. Gamon
- Department of Earth and Atmospheric Sciences and Department of Biological SciencesUniversity of AlbertaEdmontonABT6G 2E3Canada
- Center for Advanced Land Management Information TechnologiesSchool of Natural ResourcesUniversity of Nebraska–LincolnLincolnNE68583USA
| | - Anna K. Schweiger
- Department of Ecology, Evolution and BehaviorUniversity of MinnesotaSaint PaulMN55108USA
- Département de Sciences Biologiques et Institut de Recherche en Biologie VégétaleUniversité de MontréalQuébecH1X 2B2Canada
| | | | - Gregory P. Asner
- Center for Global Discovery and Conservation ScienceArizona State UniversityTempeAZ85287USA
| | - Roberta E. Martin
- Center for Global Discovery and Conservation ScienceArizona State UniversityTempeAZ85287USA
- School for Geographical Sciences and Urban PlanningArizona State UniversityTempeAZ85281USA
| | - Aditya Singh
- Department of Agricultural and Biological EngineeringUniversity of FloridaGainesvilleFL32611USA
| | - Franziska Schrodt
- School of GeographyUniversity of NottinghamNottinghamNottinghamshireNG7 2RDUK
| | - Adam Chlus
- Department of Forest and Wildlife EcologyUniversity of Wisconsin–MadisonMadisonWI53706USA
| | - Brian C. O'Meara
- Ecology and Evolutionary BiologyUniversity of TennesseeKnoxvilleTN37996USA
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42
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Chase AP, Kramer SJ, Haëntjens N, Boss ES, Karp‐Boss L, Edmondson M, Graff JR. Evaluation of diagnostic pigments to estimate phytoplankton size classes. Limnol Oceanogr Methods 2020; 18:570-584. [PMID: 33132771 PMCID: PMC7589370 DOI: 10.1002/lom3.10385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 06/01/2020] [Accepted: 07/11/2020] [Indexed: 05/19/2023]
Abstract
Phytoplankton accessory pigments are commonly used to estimate phytoplankton size classes, particularly during development and validation of biogeochemical models and satellite ocean color-based algorithms. The diagnostic pigment analysis (DPA) is based on bulk measurements of pigment concentrations and relies on assumptions regarding the presence of specific pigments in different phytoplankton taxonomic groups. Three size classes are defined by the DPA: picoplankton, nanoplankton, and microplankton. Until now, the DPA has not been evaluated against an independent approach that provides phytoplankton size calculated on a per-cell basis. Automated quantitative cell imagery of microplankton and some nanoplankton, used in combination with conventional flow cytometry for enumeration of picoplankton and nanoplankton, provide a novel opportunity to perform an independent evaluation of the DPA. Here, we use a data set from the North Atlantic Ocean that encompasses all seasons and a wide range of chlorophyll concentrations (0.18-5.14 mg m-3). Results show that the DPA overestimates microplankton and picoplankton when compared to cytometry data, and subsequently underestimates the contribution of nanoplankton to total biomass. In contrast to the assumption made by the DPA that the microplankton size class is largely made up of diatoms and dinoflagellates, imaging-in-flow cytometry shows significant presence of diatoms and dinoflagellates in the nanoplankton size class. Additionally, chlorophyll b is commonly attributed solely to picoplankton by the DPA, but Chl b-containing phytoplankton are observed with imaging in both nanoplankton and microplankton size classes. We suggest revisions to the DPA equations and application of uncertainties when calculating size classes from diagnostic pigments.
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Affiliation(s)
| | - Sasha J. Kramer
- Interdepartmental Graduate Program in Marine ScienceUniversity of California Santa BarbaraSanta BarbaraCaliforniaUSA
| | - Nils Haëntjens
- School of Marine SciencesUniversity of MaineOronoMaineUSA
| | | | - Lee Karp‐Boss
- School of Marine SciencesUniversity of MaineOronoMaineUSA
| | - Mimi Edmondson
- School of Marine SciencesUniversity of MaineOronoMaineUSA
| | - Jason R. Graff
- Department of Botany and Plant PathologyOregon State UniversityCorvallisOregonUSA
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43
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López I, Hansen VL. Geologic Map of the Niobe Planitia Region (I-2467), Venus. Earth Space Sci 2020; 7:e2020EA001171. [PMID: 33134436 PMCID: PMC7583383 DOI: 10.1029/2020ea001171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 06/09/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
We present a 1:10M scale geologic map of the Niobe Planitia region of Venus (0°N-57°N/60°E-180°E). We herein refer to this area as the Niobe Map Area (NMA). Geologic mapping employed NASA Magellan synthetic aperture radar and altimetry data. The NMA geologic map and its companion Aphrodite Map Area (AMA) cover ~25% of Venus' surface, providing an important and unique perspective to study global and regional geologic processes. Both areas display a regional coherence of preserved geologic patterns that record three sequential geologic eras: the ancient era, the Artemis superstructure era, and the youngest fracture zone era. The NMA preserves a limited record of the fracture zone era, contrary to the AMA. However, the NMA hosts a diverse and rich assemblage of material and structures of the ancient era and structures that define the Artemis superstructure era. These two eras likely overlap in time and account for the formation of basement materials and lower plain units. Impact craters formed throughout the NMA recorded history. Approximately 40% of the impact craters show interior flood deposits, indicating that a significant number of NMA impact craters experienced notable geological events after impact crater formation. This and other geologic relations record a geohistory inconsistent with postulated global catastrophic resurfacing. Together, the NMA and the AMA record a rich geologic history of the surface of Venus that provide a framework to formulate new working hypotheses of Venus evolution and to plan future studies of the planet.
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Affiliation(s)
- Iván López
- Departamento de Biología y Geología, Física y Química InorgánicaUniversidad Rey Juan CarlosMadridSpain
| | - Vicki L. Hansen
- Department of Earth and Environmental SciencesUniversity of Minnesota‐DuluthDuluthMNUSA
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44
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Leonard JM, Adam CD, Pelgrift JY, Lessac‐Chenen EJ, Nelson DS, Antreasian PG, Liounis AJ, Moreau MC, Hergenrother CW, Chesley SR, Nolan MC, Lauretta DS. Initial Orbit Determination and Event Reconstruction From Estimation of Particle Trajectories About (101955) Bennu. Earth Space Sci 2020; 7:e2019EA000937. [PMID: 33043099 PMCID: PMC7540059 DOI: 10.1029/2019ea000937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 02/10/2020] [Accepted: 02/25/2020] [Indexed: 06/11/2023]
Abstract
The OSIRIS-REx mission has observed multiple instances of particles being ejected from the surface of near-Earth asteroid (101955) Bennu. The ability to quickly identify the particle trajectories and origins is necessary following a particle ejection event. Using proven initial orbit determination techniques, we can rapidly estimate particle trajectories and ejection locations. We present current results pertaining to the identification of particle tracks, an evaluation of the estimated orbits and the excess velocity necessary to induce the particle ejection from the surface, and the uncertainty quantification of the ejection location. We estimate energies per particle ranging from 0.03 to 11.03 mJ for the largest analyzed events and velocities ranging from 5 to 90 cm/s, though we exclude the highest-velocity particles in this technique. We estimate ejection times for eight events and constrain six of the analyzed ejection events to have occurred between about 16:30 and 19:00 local solar time, with the largest events occurring between 16:30 and 18:05.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - S. R. Chesley
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | - M. C. Nolan
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | - D. S. Lauretta
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
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45
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Walcutt NL, Knörlein B, Cetinić I, Ljubesic Z, Bosak S, Sgouros T, Montalbano AL, Neeley A, Menden‐Deuer S, Omand MM. Assessment of holographic microscopy for quantifying marine particle size and concentration. Limnol Oceanogr Methods 2020; 18:516-530. [PMID: 33041697 PMCID: PMC7540046 DOI: 10.1002/lom3.10379] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/12/2020] [Accepted: 06/16/2020] [Indexed: 06/11/2023]
Abstract
Holographic microscopy has emerged as a tool for in situ imaging of microscopic organisms and other particles in the marine environment: appealing because of the relatively larger sampling volume and simpler optical configuration compared to other imaging systems. However, its quantitative capabilities have so far remained uncertain, in part because hologram reconstruction and image recognition have required manual operation. Here, we assess the quantitative skill of our automated hologram processing pipeline (CCV Pipeline), to evaluate the size and concentration measurements of environmental and cultured assemblages of marine plankton particles, and microspheres. Over 1 million particles, ranging from 10 to 200 μm in equivalent spherical diameter, imaged by the 4-Deep HoloSea digital inline holographic microscope (DIHM) are analyzed. These measurements were collected in parallel with a FlowCam (FC), Imaging FlowCytobot (IFCB), and manual microscope identification. Once corrections for particle location and nonuniform illumination were developed and applied, the DIHM showed an underestimate in ESD of about 3% to 10%, but successfully reproduced the size spectral slope from environmental samples, and the size distribution of cultures (Dunaliella tertiolecta, Heterosigma akashiwo, and Prorocentrum micans) and microspheres. DIHM concentrations (order 1 to 1000 particles ml-1) showed a linear agreement (r 2 = 0.73) with the other instruments, but individual comparisons at times had large uncertainty. Overall, we found the DIHM and the CCV Pipeline required extensive manual correction, but once corrected, provided concentration and size estimates comparable to the other imaging systems assessed in this study. Holographic cameras are mechanically simple, autonomous, can operate at very high pressures, and provide a larger sampling volume than comparable lens-based tools. Thus, we anticipate that these characterization efforts will be rewarded with novel discovery in new oceanic environments.
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Affiliation(s)
- Noah L. Walcutt
- University of Rhode Island, Graduate School of OceanographyNarragansettRhode IslandUSA
| | - Benjamin Knörlein
- Brown University, Center for Computation and VisualizationProvidenceRhode IslandUSA
| | - Ivona Cetinić
- NASA Goddard Space Flight CenterOcean Ecology LaboratoryGreenbeltMarylandUSA
- GESTAR/Universities Space Research AssociationColumbiaMarylandUSA
| | - Zrinka Ljubesic
- Faculty of Science, Department of BiologyUniversity of ZagrebZagrebCroatia
| | - Suncica Bosak
- Faculty of Science, Department of BiologyUniversity of ZagrebZagrebCroatia
| | - Tom Sgouros
- Department of Computer ScienceBrown UniversityProvidenceRhode IslandUSA
| | - Amanda L. Montalbano
- University of Rhode Island, Graduate School of OceanographyNarragansettRhode IslandUSA
| | - Aimee Neeley
- NASA Goddard Space Flight CenterOcean Ecology LaboratoryGreenbeltMarylandUSA
| | - Susanne Menden‐Deuer
- University of Rhode Island, Graduate School of OceanographyNarragansettRhode IslandUSA
| | - Melissa M. Omand
- University of Rhode Island, Graduate School of OceanographyNarragansettRhode IslandUSA
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46
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Hamlington BD, Gardner AS, Ivins E, Lenaerts JTM, Reager JT, Trossman DS, Zaron ED, Adhikari S, Arendt A, Aschwanden A, Beckley BD, Bekaert DPS, Blewitt G, Caron L, Chambers DP, Chandanpurkar HA, Christianson K, Csatho B, Cullather RI, DeConto RM, Fasullo JT, Frederikse T, Freymueller JT, Gilford DM, Girotto M, Hammond WC, Hock R, Holschuh N, Kopp RE, Landerer F, Larour E, Menemenlis D, Merrifield M, Mitrovica JX, Nerem RS, Nias IJ, Nieves V, Nowicki S, Pangaluru K, Piecuch CG, Ray RD, Rounce DR, Schlegel N, Seroussi H, Shirzaei M, Sweet WV, Velicogna I, Vinogradova N, Wahl T, Wiese DN, Willis MJ. Understanding of Contemporary Regional Sea-Level Change and the Implications for the Future. Rev Geophys 2020; 58:e2019RG000672. [PMID: 32879921 PMCID: PMC7375165 DOI: 10.1029/2019rg000672] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 03/17/2020] [Accepted: 03/19/2020] [Indexed: 06/11/2023]
Abstract
Global sea level provides an important indicator of the state of the warming climate, but changes in regional sea level are most relevant for coastal communities around the world. With improvements to the sea-level observing system, the knowledge of regional sea-level change has advanced dramatically in recent years. Satellite measurements coupled with in situ observations have allowed for comprehensive study and improved understanding of the diverse set of drivers that lead to variations in sea level in space and time. Despite the advances, gaps in the understanding of contemporary sea-level change remain and inhibit the ability to predict how the relevant processes may lead to future change. These gaps arise in part due to the complexity of the linkages between the drivers of sea-level change. Here we review the individual processes which lead to sea-level change and then describe how they combine and vary regionally. The intent of the paper is to provide an overview of the current state of understanding of the processes that cause regional sea-level change and to identify and discuss limitations and uncertainty in our understanding of these processes. Areas where the lack of understanding or gaps in knowledge inhibit the ability to provide the needed information for comprehensive planning efforts are of particular focus. Finally, a goal of this paper is to highlight the role of the expanded sea-level observation network-particularly as related to satellite observations-in the improved scientific understanding of the contributors to regional sea-level change.
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47
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Noonan MJ, Fleming CH, Tucker MA, Kays R, Harrison A, Crofoot MC, Abrahms B, Alberts SC, Ali AH, Altmann J, Antunes PC, Attias N, Belant JL, Beyer DE, Bidner LR, Blaum N, Boone RB, Caillaud D, de Paula RC, de la Torre JA, Dekker J, DePerno CS, Farhadinia M, Fennessy J, Fichtel C, Fischer C, Ford A, Goheen JR, Havmøller RW, Hirsch BT, Hurtado C, Isbell LA, Janssen R, Jeltsch F, Kaczensky P, Kaneko Y, Kappeler P, Katna A, Kauffman M, Koch F, Kulkarni A, LaPoint S, Leimgruber P, Macdonald DW, Markham AC, McMahon L, Mertes K, Moorman CE, Morato RG, Moßbrucker AM, Mourão G, O'Connor D, Oliveira‐Santos LGR, Pastorini J, Patterson BD, Rachlow J, Ranglack DH, Reid N, Scantlebury DM, Scott DM, Selva N, Sergiel A, Songer M, Songsasen N, Stabach JA, Stacy‐Dawes J, Swingen MB, Thompson JJ, Ullmann W, Vanak AT, Thaker M, Wilson JW, Yamazaki K, Yarnell RW, Zieba F, Zwijacz‐Kozica T, Fagan WF, Mueller T, Calabrese JM. Effects of body size on estimation of mammalian area requirements. Conserv Biol 2020; 34:1017-1028. [PMID: 32362060 PMCID: PMC7496598 DOI: 10.1111/cobi.13495] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/27/2019] [Accepted: 12/24/2019] [Indexed: 06/08/2023]
Abstract
Accurately quantifying species' area requirements is a prerequisite for effective area-based conservation. This typically involves collecting tracking data on species of interest and then conducting home-range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home-range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross-validation to quantify bias in empirical home-range estimates. Area requirements of mammals <10 kg were underestimated by a mean approximately15%, and species weighing approximately100 kg were underestimated by approximately50% on average. Thus, we found area estimation was subject to autocorrelation-induced bias that was worse for large species. Combined with the fact that extinction risk increases as body mass increases, the allometric scaling of bias we observed suggests the most threatened species are also likely to be those with the least accurate home-range estimates. As a correction, we tested whether data thinning or autocorrelation-informed home-range estimation minimized the scaling effect of autocorrelation on area estimates. Data thinning required an approximately93% data loss to achieve statistical independence with 95% confidence and was, therefore, not a viable solution. In contrast, autocorrelation-informed home-range estimation resulted in consistently accurate estimates irrespective of mass. When relating body mass to home range size, we detected that correcting for autocorrelation resulted in a scaling exponent significantly >1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum.
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Affiliation(s)
- Michael J. Noonan
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
- Department of BiologyUniversity of MarylandCollege ParkMD20742U.S.A.
| | - Christen H. Fleming
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
- Department of BiologyUniversity of MarylandCollege ParkMD20742U.S.A.
| | - Marlee A. Tucker
- Senckenberg Biodiversity and Climate Research CentreSenckenberg Gesellschaft für NaturforschungSenckenberganlage 25Frankfurt (Main)60325Germany
- Department of Biological SciencesGoethe UniversityMax‐von‐Laue‐Straße 9Frankfurt (Main)60438Germany
- Department of Environmental ScienceInstitute for Wetland and Water ResearchRadboud UniversityP.O. Box 9010NijmegenGLNL‐6500The Netherlands
| | - Roland Kays
- North Carolina Museum of Natural SciencesBiodiversity LabRaleighNC27601U.S.A.
- Fisheries, Wildlife, and Conservation Biology Program, College of Natural Resources Campus Box 8001North Carolina State UniversityRaleighNC27695U.S.A.
| | - Autumn‐Lynn Harrison
- Migratory Bird CenterSmithsonian Conservation Biology InstituteWashingtonD.C.20013U.S.A.
| | - Margaret C. Crofoot
- Department of AnthropologyUniversity of California, DavisDavisCA95616U.S.A.
- Smithsonian Tropical Research InstituteBalboa Ancon0843‐03092Republic of Panama
| | - Briana Abrahms
- Environmental Research DivisionNOAA Southwest Fisheries Science CenterMontereyCA93940U.S.A.
| | - Susan C. Alberts
- Departments of Biology and Evolutionary AnthropologyDuke UniversityDurhamNC27708U.S.A.
| | | | - Jeanne Altmann
- Department of Ecology and EvolutionPrinceton University106A Guyot HallPrincetonNJ08544U.S.A.
| | - Pamela Castro Antunes
- Department of EcologyFederal University of Mato Grosso do SulCampo GrandeMS79070–900Brazil
| | - Nina Attias
- Programa de Pós‐Graduaçao em Biologia Animal, Universidade Federal do Mato Grosso do SulCidade UniversitáriaAv. Costa e SilvaCampo GrandeMato Grosso do Sul79070‐900Brazil
| | - Jerrold L. Belant
- Camp Fire Program in Wildlife Conservation, State University of New YorkCollege of Environmental Science and ForestrySyracuseNY13210U.S.A.
| | - Dean E. Beyer
- Michigan Department of Natural Resources1990 U.S. 41 SouthMarquetteMI49855U.S.A.
| | - Laura R. Bidner
- Department of AnthropologyUniversity of California, DavisDavisCA95616U.S.A.
- Mpala Research CentreNanyuki555–104000Kenya
| | - Niels Blaum
- University of Potsdam, Plant Ecology and Nature ConservationAm Mühlenberg 3Potsdam14476Germany
| | - Randall B. Boone
- Natural Resource Ecology LaboratoryColorado State UniversityFort CollinsCO80523U.S.A.
- Department of Ecosystem Science and SustainabilityColorado State UniversityFort CollinsCO80523U.S.A.
| | - Damien Caillaud
- Department of AnthropologyUniversity of California, DavisDavisCA95616U.S.A.
| | - Rogerio Cunha de Paula
- National Research Center for Carnivores ConservationChico Mendes Institute for the Conservation of BiodiversityEstrada Municipal Hisaichi Takebayashi 8600AtibaiaSP12952‐011Brazil
| | - J. Antonio de la Torre
- Instituto de Ecología, Universidad Nacional Autónoma de Mexico and CONACyTCiudad UniversitariaMexicoD.F.04318Mexico
| | - Jasja Dekker
- Jasja Dekker DierecologieEnkhuizenstraat 26ArnhemWZ6843The Netherlands
| | - Christopher S. DePerno
- Fisheries, Wildlife, and Conservation Biology Program, College of Natural Resources Campus Box 8001North Carolina State UniversityRaleighNC27695U.S.A.
| | - Mohammad Farhadinia
- Wildlife Conservation Research Unit, Department of ZoologyUniversity of OxfordTubney House, OxfordshireOxfordOX13 5QLU.K.
- Future4Leopards FoundationTehranIran
| | | | - Claudia Fichtel
- German Primate CenterBehavioral Ecology & Sociobiology UnitKellnerweg 4Göttingen37077Germany
| | - Christina Fischer
- Restoration Ecology, Department of Ecology and Ecosystem ManagementTechnische Universität MünchenEmil‐Ramann‐Straße 6Freising85354Germany
| | - Adam Ford
- The Irving K. Barber School of Arts and Sciences, Unit 2: BiologyThe University of British ColumbiaOkanagan Campus, SCI 109, 1177 Research RoadKelownaBCV1V 1V7Canada
| | - Jacob R. Goheen
- Department of Zoology and PhysiologyUniversity of WyomingLaramieWY82071U.S.A.
| | | | - Ben T. Hirsch
- Zoology and Ecology, College of Science and EngineeringJames Cook UniversityTownsvilleQLD4811Australia
| | - Cindy Hurtado
- Museo de Historia NaturalUniversidad Nacional Mayor de San MarcosLima15072Peru
- Department of Forest Resources ManagementThe University of British ColumbiaVancouverBCV6T 1Z4Canada
| | - Lynne A. Isbell
- Department of AnthropologyUniversity of California, DavisDavisCA95616U.S.A.
- Mpala Research CentreNanyuki555–104000Kenya
| | - René Janssen
- Bionet NatuuronderzoekValderstraat 39Stein6171ELThe Netherlands
| | - Florian Jeltsch
- University of Potsdam, Plant Ecology and Nature ConservationAm Mühlenberg 3Potsdam14476Germany
| | - Petra Kaczensky
- Norwegian Institute for Nature Research — NINASluppenTrondheimNO‐7485Norway
- Research Institute of Wildlife Ecology, University of Veterinary MedicineSavoyenstraße 1ViennaA‐1160Austria
| | - Yayoi Kaneko
- Tokyo University of Agriculture and TechnologyTokyo183–8509Japan
| | - Peter Kappeler
- German Primate CenterBehavioral Ecology & Sociobiology UnitKellnerweg 4Göttingen37077Germany
| | - Anjan Katna
- Ashoka Trust for Research in Ecology and the Environment (ATREE)BangaloreKarnataka560064India
- Manipal Academy of Higher EducationManipalKarnataka576104India
| | - Matthew Kauffman
- U.S. Geological Survey, Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and PhysiologyUniversity of WyomingLaramieWY82071U.S.A.
| | - Flavia Koch
- German Primate CenterBehavioral Ecology & Sociobiology UnitKellnerweg 4Göttingen37077Germany
| | - Abhijeet Kulkarni
- Ashoka Trust for Research in Ecology and the Environment (ATREE)BangaloreKarnataka560064India
| | - Scott LaPoint
- Max Planck Institute for OrnithologyVogelwarte RadolfzellAm Obstberg 1RadolfzellD‐78315Germany
- Black Rock Forest65 Reservoir RoadCornwallNY12518U.S.A.
| | - Peter Leimgruber
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
| | - David W. Macdonald
- Wildlife Conservation Research Unit, Department of ZoologyUniversity of OxfordTubney House, OxfordshireOxfordOX13 5QLU.K.
| | | | - Laura McMahon
- Office of Applied ScienceDepartment of Natural ResourcesRhinelanderWI54501U.S.A.
| | - Katherine Mertes
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
| | - Christopher E. Moorman
- Fisheries, Wildlife, and Conservation Biology Program, College of Natural Resources Campus Box 8001North Carolina State UniversityRaleighNC27695U.S.A.
| | - Ronaldo G. Morato
- National Research Center for Carnivores ConservationChico Mendes Institute for the Conservation of BiodiversityEstrada Municipal Hisaichi Takebayashi 8600AtibaiaSP12952‐011Brazil
- Institute for the Conservation of Neotropical Carnivores – Pró‐CarnívorosAtibaiaSao Paulo12945‐010Brazil
| | | | - Guilherme Mourão
- Embrapa PantanalRua 21 de setembro 1880Corumb´aMS79320–900Brazil
| | - David O'Connor
- Department of Biological SciencesGoethe UniversityMax‐von‐Laue‐Straße 9Frankfurt (Main)60438Germany
- San Diego Zoo Institute of Conservation Research15600 San Pasqual Valley RoadEscondidoCA92027U.S.A.
- National Geographic Partners1145 17th Street NWWashingtonD.C.20036U.S.A.
| | | | - Jennifer Pastorini
- Centre for Conservation and Research26/7 C2 Road, KodigahawewaJulpallamaTissamaharama82600Sri Lanka
- Anthropologisches InstitutUniversität ZürichWinterthurerstrasse 190Zurich8057Switzerland
| | - Bruce D. Patterson
- Integrative Research CenterField Museum of Natural HistoryChicagoIL60605U.S.A.
| | - Janet Rachlow
- Department of Fish and Wildlife SciencesUniversity of Idaho875 Perimeter Drive MS 1136MoscowID83844‐1136U.S.A.
| | - Dustin H. Ranglack
- Department of BiologyUniversity of Nebraska at KearneyKearneyNE68849U.S.A.
| | - Neil Reid
- Institute for Global Food Security (IGFS), School of Biological SciencesQueen's University BelfastBelfastBT9 5DLU.K.
| | - David M. Scantlebury
- School of Biological SciencesQueen's University Belfast19 Chlorine GardensBelfastNorthern IrelandBT9 5DLU.K.
| | - Dawn M. Scott
- School of Life SciencesKeele UniversityKeeleStaffordshireST5 5BGU.K.
| | - Nuria Selva
- Institute of Nature ConservationPolish Academy of SciencesMickiewicza 33Krakow31–120Poland
| | - Agnieszka Sergiel
- Institute of Nature ConservationPolish Academy of SciencesMickiewicza 33Krakow31–120Poland
| | - Melissa Songer
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
| | - Nucharin Songsasen
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
| | - Jared A. Stabach
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
| | - Jenna Stacy‐Dawes
- San Diego Zoo Institute of Conservation Research15600 San Pasqual Valley RoadEscondidoCA92027U.S.A.
| | - Morgan B. Swingen
- Fisheries, Wildlife, and Conservation Biology Program, College of Natural Resources Campus Box 8001North Carolina State UniversityRaleighNC27695U.S.A.
- 1854 Treaty Authority4428 Haines RoadDuluthMN55811U.S.A.
| | - Jeffrey J. Thompson
- Asociación Guyra Paraguay – CONACYTParque Ecológico Asunción VerdeAsuncion1101Paraguay
- Instituto SaiteCoronel Felix Cabrera 166Asuncion1101Paraguay
| | - Wiebke Ullmann
- University of Potsdam, Plant Ecology and Nature ConservationAm Mühlenberg 3Potsdam14476Germany
| | - Abi Tamim Vanak
- Ashoka Trust for Research in Ecology and the Environment (ATREE)BangaloreKarnataka560064India
- Wellcome Trust/DBT India AllianceHyderabad500034India
- School of Life SciencesUniversity of KwaZulu‐NatalWestvilleDurban4041South Africa
| | - Maria Thaker
- Centre for Ecological SciencesIndian Institute of ScienceBangalore560012India
| | - John W. Wilson
- Department of Zoology & EntomologyUniversity of PretoriaPretoria0002South Africa
| | - Koji Yamazaki
- Ibaraki Nature MuseumZoological Laboratory700 OsakiBando‐cityIbaraki306–0622Japan
- Forest Ecology LaboratoryDepartment of Forest ScienceTokyo University of Agriculture1‐1‐1 SakuragaokaSetagaya‐KuTokyo156–8502Japan
| | - Richard W. Yarnell
- School of Animal, Rural and Environmental SciencesNottingham Trent UniversityBrackenhurst CampusSouthwellNG25 0QFU.K.
| | - Filip Zieba
- Tatra National ParkKúznice 1Zakopane34–500Poland
| | | | - William F. Fagan
- Department of BiologyUniversity of MarylandCollege ParkMD20742U.S.A.
| | - Thomas Mueller
- Senckenberg Biodiversity and Climate Research CentreSenckenberg Gesellschaft für NaturforschungSenckenberganlage 25Frankfurt (Main)60325Germany
- Department of Biological SciencesGoethe UniversityMax‐von‐Laue‐Straße 9Frankfurt (Main)60438Germany
| | - Justin M. Calabrese
- Smithsonian Conservation Biology InstituteNational Zoological Park1500 Remount RoadFront RoyalVA22630U.S.A.
- Department of BiologyUniversity of MarylandCollege ParkMD20742U.S.A.
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Schlunegger S, Rodgers KB, Sarmiento JL, Ilyina T, Dunne JP, Takano Y, Christian JR, Long MC, Frölicher TL, Slater R, Lehner F. Time of Emergence and Large Ensemble Intercomparison for Ocean Biogeochemical Trends. Global Biogeochem Cycles 2020; 34:e2019GB006453. [PMID: 32999530 PMCID: PMC7507776 DOI: 10.1029/2019gb006453] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 04/24/2020] [Accepted: 07/11/2020] [Indexed: 05/31/2023]
Abstract
Anthropogenically forced changes in ocean biogeochemistry are underway and critical for the ocean carbon sink and marine habitat. Detecting such changes in ocean biogeochemistry will require quantification of the magnitude of the change (anthropogenic signal) and the natural variability inherent to the climate system (noise). Here we use Large Ensemble (LE) experiments from four Earth system models (ESMs) with multiple emissions scenarios to estimate Time of Emergence (ToE) and partition projection uncertainty for anthropogenic signals in five biogeochemically important upper-ocean variables. We find ToEs are robust across ESMs for sea surface temperature and the invasion of anthropogenic carbon; emergence time scales are 20-30 yr. For the biological carbon pump, and sea surface chlorophyll and salinity, emergence time scales are longer (50+ yr), less robust across the ESMs, and more sensitive to the forcing scenario considered. We find internal variability uncertainty, and model differences in the internal variability uncertainty, can be consequential sources of uncertainty for projecting regional changes in ocean biogeochemistry over the coming decades. In combining structural, scenario, and internal variability uncertainty, this study represents the most comprehensive characterization of biogeochemical emergence time scales and uncertainty to date. Our findings delineate critical spatial and duration requirements for marine observing systems to robustly detect anthropogenic change.
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Affiliation(s)
- Sarah Schlunegger
- Program in Atmospheric and Oceanic SciencesPrinceton UniversityPrincetonNJUSA
| | - Keith B. Rodgers
- Program in Atmospheric and Oceanic SciencesPrinceton UniversityPrincetonNJUSA
- Center for Climate PhysicsInstitute for Basic ScienceBusanSouth Korea
- Pusan National UniversityBusanSouth Korea
| | - Jorge L. Sarmiento
- Program in Atmospheric and Oceanic SciencesPrinceton UniversityPrincetonNJUSA
| | | | - John P. Dunne
- NOAA Geophysical Fluid Dynamics LaboratoryPrincetonNJUSA
| | - Yohei Takano
- Max Plank Institute for MeteorologyHamburgGermany
- Los Alamos National LaboratoryLos AlamosNMUSA
| | - James R. Christian
- Canadian Center for Climate Modeling and AnalysisVictoriaBritish ColumbiaCanada
| | | | - Thomas L. Frölicher
- Climate and Environmental Physics, Physics InstituteUniversity of BernBernSwitzerland
- Oeschger Centre for Climate Change ResearchUniversity of BernBernSwitzerland
| | - Richard Slater
- Program in Atmospheric and Oceanic SciencesPrinceton UniversityPrincetonNJUSA
| | - Flavio Lehner
- National Center for Atmospheric ResearchBoulderCOUSA
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49
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Molaro JL, Hergenrother CW, Chesley SR, Walsh KJ, Hanna RD, Haberle CW, Schwartz SR, Ballouz R, Bottke WF, Campins HJ, Lauretta DS. Thermal Fatigue as a Driving Mechanism for Activity on Asteroid Bennu. J Geophys Res Planets 2020; 125:e2019JE006325. [PMID: 32999800 PMCID: PMC7507781 DOI: 10.1029/2019je006325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 07/15/2020] [Accepted: 07/18/2020] [Indexed: 06/11/2023]
Abstract
Many boulders on (101955) Bennu, a near-Earth rubble pile asteroid, show signs of in situ disaggregation and exfoliation, indicating that thermal fatigue plays an important role in its landscape evolution. Observations of particle ejections from its surface also show it to be an active asteroid, though the driving mechanism of these events is yet to be determined. Exfoliation has been shown to mobilize disaggregated particles in terrestrial environments, suggesting that it may be capable of ejecting material from Bennu's surface. We investigate the nature of thermal fatigue on the asteroid, and the efficacy of fatigue-driven exfoliation as a mechanism for generating asteroid activity, by performing finite element modeling of stress fields induced in boulders from diurnal cycling. We develop a model to predict the spacing of exfoliation fractures and the number and speed of particles that may be ejected during exfoliation events. We find that crack spacing ranges from ~1 mm to 10 cm and disaggregated particles have ejection speeds up to ~2 m/s. Exfoliation events are most likely to occur in the late afternoon. These predictions are consistent with observed ejection events at Bennu and indicate that thermal fatigue is a viable mechanism for driving asteroid activity. Crack propagation rates and ejection speeds are greatest at perihelion when the diurnal temperature variation is largest, suggesting that events should be more energetic and more frequent when closer to the Sun. Annual thermal stresses that arise in large boulders may influence the spacing of exfoliation cracks or frequency of ejection events.
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Affiliation(s)
| | | | - S. R. Chesley
- Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaCAUSA
| | | | - R. D. Hanna
- Jackson School of GeosciencesUniversity of Texas at AustinAustinTXUSA
| | - C. W. Haberle
- School of Earth and Space ExplorationArizona State UniversityTempeAZUSA
| | - S. R. Schwartz
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | - R.‐L. Ballouz
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
| | | | - H. J. Campins
- Department of PhysicsUniversity of Central FloridaOrlandoFLUSA
| | - D. S. Lauretta
- Lunar and Planetary LaboratoryUniversity of ArizonaTucsonAZUSA
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50
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Bendixsen DP, M Roberts J, Townshend B, Hayden EJ. Phased nucleotide inserts for sequencing low-diversity RNA samples from in vitro selection experiments. RNA 2020; 26:1060-1068. [PMID: 32300045 PMCID: PMC7373987 DOI: 10.1261/rna.072413.119] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 04/09/2020] [Indexed: 05/06/2023]
Abstract
In vitro selection combined with high-throughput sequencing is a powerful experimental approach with broad application in the engineering and characterization of RNA molecules. Diverse pools of starting sequences used for selection are often flanked by fixed sequences used as primer binding sites. These low diversity regions often lead to data loss from complications with Illumina image processing algorithms. A common method to alleviate this problem is the addition of fragmented bacteriophage PhiX genome, which improves sequence quality but sacrifices a portion of usable sequencing reads. An alternative approach is to insert nucleotides of variable length and composition ("phased inserts") at the beginning of each molecule when adding sequencing adaptors. This approach preserves read depth but reduces the length of each read. Here, we test the ability of phased inserts to replace PhiX in a low-diversity sample generated for a high-throughput sequencing based ribozyme activity screen. We designed a pool of 4096 RNA sequence variants of the self-cleaving twister ribozyme from Oryza sativa For each unique sequence, we determined the fraction of ribozyme cleaved during in vitro transcription via deep sequencing on an Illumina MiSeq. We found that libraries with the phased inserts produced high-quality sequence data without the addition of PhiX. We found good agreement between previously published data on twister ribozyme variants and our data produced with phased inserts even when PhiX was omitted. We conclude that phased inserts can be implemented following in vitro selection experiments to reduce or eliminate the use of PhiX and maximize read depth.
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Affiliation(s)
- Devin P Bendixsen
- Biomolecular Sciences Graduate Programs, Boise State University, Boise, Idaho 83725, USA
| | - Jessica M Roberts
- Biomolecular Sciences Graduate Programs, Boise State University, Boise, Idaho 83725, USA
| | - Brent Townshend
- Department of Bioengineering, Stanford University, Stanford, California 94305, USA
| | - Eric J Hayden
- Biomolecular Sciences Graduate Programs, Boise State University, Boise, Idaho 83725, USA
- Department of Biological Sciences, Boise State University, Boise, Idaho 83725, USA
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