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Wolfenbarger NS, Buffo JJ, Soderlund KM, Blankenship DD. Ice Shell Structure and Composition of Ocean Worlds: Insights from Accreted Ice on Earth. ASTROBIOLOGY 2022; 22:937-961. [PMID: 35787145 DOI: 10.1089/ast.2021.0044] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Accreted ice retains and preserves traces of the ocean from which it formed. In this work, we study two classes of accreted ice found on Earth-frazil ice, which forms through crystallization within a supercooled water column, and congelation ice, which forms through directional freezing at an existing interface-and discuss where each might be found in the ice shells of ocean worlds. We focus our study on terrestrial ice formed in low temperature gradient environments (e.g., beneath ice shelves), consistent with conditions expected at the ice-ocean interfaces of Europa and Enceladus, and we highlight the juxtaposition of compositional trends in relation to ice formed in higher temperature gradient environments (e.g., at the ocean surface). Observations from Antarctic sub-ice-shelf congelation ice and marine ice show that the purity of frazil ice can be nearly two orders of magnitude higher than congelation ice formed in the same low temperature gradient environment (∼0.1% vs. ∼10% of the ocean salinity). In addition, where congelation ice can maintain a planar ice-water interface on a microstructural scale, the efficiency of salt rejection is enhanced (∼1% of the ocean salinity) and lattice soluble impurities such as chloride are preferentially incorporated. We conclude that an ice shell that forms by gradual thickening as its interior cools would be composed of congelation ice, whereas frazil ice will accumulate where the ice shell thins on local (rifts and basal fractures) or regional (latitudinal gradients) scales through the operation of an "ice pump."
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Affiliation(s)
| | - Jacob J Buffo
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire, USA
| | - Krista M Soderlund
- Institute for Geophysics, University of Texas at Austin, Austin, Texas, USA
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Automatically Extracted Antarctic Coastline Using Remotely-Sensed Data: An Update. REMOTE SENSING 2019. [DOI: 10.3390/rs11161844] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The temporal and spatial variability of the Antarctic coastline is a clear indicator of change in extent and mass balance of ice sheets and shelves. In this study, the Canny edge detector was utilized to automatically extract high-resolution information of the Antarctic coastline for 2005, 2010, and 2017, based on optical and microwave satellite data. In order to improve the accuracy of the extracted coastlines, we developed the Canny algorithm by automatically calculating the local low and high thresholds via the intensity histogram of each image to derive thresholds to distinguish ice sheet from water. A visual comparison between extracted coastlines and mosaics from remote sensing images shows good agreement. In addition, comparing manually extracted coastline, based on prior knowledge, the accuracy of planimetric position of automated extraction is better than two pixels of Landsat images (30 m resolution). Our study shows that the percentage of deviation (<100 m) between automatically and manually extracted coastlines in nine areas around the Antarctica is 92.32%, and the mean deviation is 38.15 m. Our results reveal that the length of coastline around Antarctica increased from 35,114 km in 2005 to 35,281 km in 2010, and again to 35,672 km in 2017. Meanwhile, the total area of the Antarctica varied slightly from 1.3618 × 107 km2 (2005) to 1.3537 × 107 km2 (2010) and 1.3657 × 107 km2 (2017). We have found that the decline of the Antarctic area between 2005 and 2010 is related to the breakup of some individual ice shelves, mainly in the Antarctic Peninsula and off East Antarctica. We present a detailed analysis of the temporal and spatial change of coastline and area change for the six ice shelves that exhibited the largest change in the last decade. The largest area change (a loss of 4836 km2) occurred at the Wilkins Ice Shelf between 2005 and 2010.
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Dall'Osto M, Ovadnevaite J, Paglione M, Beddows DCS, Ceburnis D, Cree C, Cortés P, Zamanillo M, Nunes SO, Pérez GL, Ortega-Retuerta E, Emelianov M, Vaqué D, Marrasé C, Estrada M, Sala MM, Vidal M, Fitzsimons MF, Beale R, Airs R, Rinaldi M, Decesari S, Cristina Facchini M, Harrison RM, O'Dowd C, Simó R. Antarctic sea ice region as a source of biogenic organic nitrogen in aerosols. Sci Rep 2017; 7:6047. [PMID: 28729547 PMCID: PMC5519629 DOI: 10.1038/s41598-017-06188-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 06/12/2017] [Indexed: 11/17/2022] Open
Abstract
Climate warming affects the development and distribution of sea ice, but at present the evidence of polar ecosystem feedbacks on climate through changes in the atmosphere is sparse. By means of synergistic atmospheric and oceanic measurements in the Southern Ocean near Antarctica, we present evidence that the microbiota of sea ice and sea ice-influenced ocean are a previously unknown significant source of atmospheric organic nitrogen, including low molecular weight alkyl-amines. Given the keystone role of nitrogen compounds in aerosol formation, growth and neutralization, our findings call for greater chemical and source diversity in the modelling efforts linking the marine ecosystem to aerosol-mediated climate effects in the Southern Ocean.
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Affiliation(s)
- Manuel Dall'Osto
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain.
| | - Jurgita Ovadnevaite
- School of Physics and Centre for Climate and Air Pollution Studies, Ryan Institute, National University of Ireland Galway, University Road, Galway, Ireland
| | - Marco Paglione
- Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, 40129, Italy
| | - David C S Beddows
- National Centre for Atmospheric Science, The School of Geography, Earth and Environmental Sciences, The University of Birmigham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Darius Ceburnis
- School of Physics and Centre for Climate and Air Pollution Studies, Ryan Institute, National University of Ireland Galway, University Road, Galway, Ireland
| | - Charlotte Cree
- Biogeochemistry Research Centre, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, UK
| | - Pau Cortés
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Marina Zamanillo
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Sdena O Nunes
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Gonzalo L Pérez
- Instituto INIBIOMA, CRUB Comahue, CONICET, Quintral 1250, 8400S.C. de Bariloche, Rio Negro, Argentina
| | - Eva Ortega-Retuerta
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Mikhail Emelianov
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Dolors Vaqué
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Cèlia Marrasé
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Marta Estrada
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - M Montserrat Sala
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
| | - Montserrat Vidal
- Department of Evolutionary Biology, Ecology and Environmental Sciences, Universitat de Barcelona, Av. Diagonal 643, 08028, Barcelona, Catalonia, Spain
| | - Mark F Fitzsimons
- Biogeochemistry Research Centre, University of Plymouth, Drake Circus, Plymouth, PL4 8AA, UK
| | - Rachael Beale
- Plymouth Marine Laboratory, Prospect Place, Plymouth, PL1 3DH, UK
| | - Ruth Airs
- Plymouth Marine Laboratory, Prospect Place, Plymouth, PL1 3DH, UK
| | - Matteo Rinaldi
- Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, 40129, Italy
| | - Stefano Decesari
- Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, 40129, Italy
| | - Maria Cristina Facchini
- Institute of Atmospheric Sciences and Climate, National Research Council, Bologna, 40129, Italy
| | - Roy M Harrison
- National Centre for Atmospheric Science, The School of Geography, Earth and Environmental Sciences, The University of Birmigham, Edgbaston, Birmingham, B15 2TT, United Kingdom.,Department of Environmental Sciences / Center of Excellence in Environmental Studies, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia
| | - Colin O'Dowd
- School of Physics and Centre for Climate and Air Pollution Studies, Ryan Institute, National University of Ireland Galway, University Road, Galway, Ireland
| | - Rafel Simó
- Institut de Ciències del Mar, CSIC, Pg. Marítim de la Barceloneta 37-49, 08003, Barcelona, Catalonia, Spain
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Monti M, Zoccarato L, Fonda Umani S. Microzooplankton composition under the sea ice and in the open waters in Terra Nova Bay (Antarctica). Polar Biol 2016. [DOI: 10.1007/s00300-016-2016-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Petrou K, Kranz SA, Doblin MA, Ralph PJ. PHOTOPHYSIOLOGICAL RESPONSES OF FRAGILARIOPSIS CYLINDRUS (BACILLARIOPHYCEAE) TO NITROGEN DEPLETION AT TWO TEMPERATURES(1). JOURNAL OF PHYCOLOGY 2012; 48:127-136. [PMID: 27009657 DOI: 10.1111/j.1529-8817.2011.01107.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The photosynthetic efficiency and photoprotective capacity of the sea-ice diatom, Fragilariopsis cylindrus (Grunow) W. Krieg., grown in a matrix of nitrogen repletion and depletion at two different temperatures (-1°C and +6°C) was investigated. Temperature showed no significant effect on photosynthetic efficiency or photoprotection in F. cylindrus. Cultures under nitrogen depletion showed enhanced photoprotective capacity with an increase in nonphotochemical quenching (NPQ) when compared with nitrogen-replete cultures. This phenomenon was achieved at no apparent cost to the photosynthetic efficiency of PSII (FV /FM ). Nitrogen depletion yielded a partially reduced electron transport chain in which maximum fluorescence (FM ) could only be obtained by adding 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU). reoxidation curves showed the presence of QB nonreducing PSII centers under nitrogen depletion. Fast induction curves (FICs) and electron transport rates (ETRs) revealed slowing of the electrons transferred from the primary (QA ) to the secondary (QB ) quinone electron acceptors of PSII. The data presented show that nitrogen depletion in F. cylindrus leads to the formation of QB nonreducing PSII centers within the photosystem. On a physiological level, the formation of QB nonreducing PSII centers in F. cylindrus provides the cell with protection against photoinhibition by facilitating the rapid induction of NPQ. This strategy provides an important ecological advantage, especially during the Antarctic spring, maintaining photosynthetic efficiency under high light and nutrient-limiting conditions.
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Affiliation(s)
- Katherina Petrou
- Plant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, AustraliaAlfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, GermanyPlant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, Australia
| | - Sven A Kranz
- Plant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, AustraliaAlfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, GermanyPlant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, Australia
| | - Martina A Doblin
- Plant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, AustraliaAlfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, GermanyPlant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, Australia
| | - Peter J Ralph
- Plant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, AustraliaAlfred Wegener Institute for Polar and Marine Research, Am Handelshafen 12, D-27570 Bremerhaven, GermanyPlant Functional Biology and Climate Change Cluster and Department of Environmental Sciences, University of Technology, Sydney, PO Box 123, Broadway NSW 2007, Australia
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Ferrario ME, Cefarelli AO, Robison B, Vernet M. THALASSIONEIS SIGNYENSIS (BACILLARIOPHYCEAE) FROM NORTHWEST WEDDELL SEA ICEBERGS, AN EMENDATION OF THE GENERIC DESCRIPTION(1). JOURNAL OF PHYCOLOGY 2012; 48:222-230. [PMID: 27009666 DOI: 10.1111/j.1529-8817.2011.01097.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We offer an emended description of the genus Thalassioneis based on new observations of the type species, T. signyensis Round, from material sampled in the northwest Weddell Sea. Specimens from algal communities attached to submerged flanks of several icebergs were collected with a remote-operated vehicle (ROV-Phantom DS 2). The analyses were carried out by LM and SEM. Fresh material and frustules without organic matter allowed us to observe details not included in the original description such as type and structure of colonies and chloroplasts. The frustule shows an asymmetry with respect to the location of the apical pore fields, one of them situated on the valvar face and the other one displaced toward the mantle; the former is involved in joining contiguous cells to form long chains. Furthermore, we present details on the ultrastructure of the cingulum that consists of three to four open copulae with one or more rows of poroids. A brief discussion on the habit and ecology of this taxon, which may be endemic to the northwest Weddell Sea, is also presented. A comparison with similar genera, such as Brandinia, Creania, Fossula, Fragilaria, Rimoneis, Synedropsis, and Ulnaria, is included with an evaluation of morphological characteristics useful to differentiate them.
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Affiliation(s)
- Martha E Ferrario
- División Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917 1033, Buenos Aires, ArgentinaDivisión Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, ArgentinaMonterey Bay Aquarium Research Institute, Moss Landing, California 95039, USAIntegrative Oceanography Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0218, USA
| | - Adrián O Cefarelli
- División Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917 1033, Buenos Aires, ArgentinaDivisión Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, ArgentinaMonterey Bay Aquarium Research Institute, Moss Landing, California 95039, USAIntegrative Oceanography Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0218, USA
| | - Bruce Robison
- División Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917 1033, Buenos Aires, ArgentinaDivisión Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, ArgentinaMonterey Bay Aquarium Research Institute, Moss Landing, California 95039, USAIntegrative Oceanography Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0218, USA
| | - María Vernet
- División Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917 1033, Buenos Aires, ArgentinaDivisión Científica Ficología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, ArgentinaMonterey Bay Aquarium Research Institute, Moss Landing, California 95039, USAIntegrative Oceanography Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, California 92093-0218, USA
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Bayer-Giraldi M, Uhlig C, John U, Mock T, Valentin K. Antifreeze proteins in polar sea ice diatoms: diversity and gene expression in the genus Fragilariopsis. Environ Microbiol 2010; 12:1041-52. [PMID: 20105220 DOI: 10.1111/j.1462-2920.2009.02149.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Fragilariopsis is a dominating psychrophilic diatom genus in polar sea ice. The two species Fragilariopsis cylindrus and Fragilariopsis curta are able to grow and divide below freezing temperature of sea water and above average sea water salinity. Here we show that antifreeze proteins (AFPs), involved in cold adaptation in several psychrophilic organisms, are widespread in the two polar species. The presence of AFP genes (afps) as a multigene family indicated the importance of this group of genes for the genus Fragilariopsis, possibly contributing to its success in sea ice. Protein phylogeny showed the potential mobility of afps, which appear to have crossed kingdom and domain borders, occurring in Bacteria, diatoms, crustaceans and fungi. Our results revealed a broad distribution of AFPs not only in polar organisms but also in taxa apparently not related to cold environments, suggesting that these proteins may be multifunctional. The relevance of AFPs to Fragilariopsis was also shown by gene expression analysis. Under stress conditions typical for sea ice, with subzero temperatures and high salinities, F. cylindrus and F. curta strongly expressed selected afps. An E/G point mutation in the Fragilariopsis AFPs may play a role in gene expression activity and protein function.
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Pieńkowski AJ, Marret F, Thomas DN, Scourse JD, Dieckmann GS. Dinoflagellates in a fast-ice covered inlet of the Riiser-Larsen Ice Shelf (Weddell Sea). Polar Biol 2009. [DOI: 10.1007/s00300-009-0630-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Population dynamics of an ice-associated diatom, Thalassiosira australis Peragallo, under fast ice near Syowa Station, East Antarctica, during austral summer. Polar Biol 2008. [DOI: 10.1007/s00300-008-0444-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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