1
|
Tropopause Characteristics Based on Long-Term ARM Radiosonde Data: A Fine-Scale Comparison at the Extratropical SGP Site and Arctic NSA Site. ATMOSPHERE 2022. [DOI: 10.3390/atmos13060965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The variations in the characteristics of the tropopause are sensitive indicators for the climate system and climate change. By using Atmospheric Radiation Measurement (ARM) radiosonde data that were recorded at the extratropical Southern Great Plains (SGP) and Arctic North Slope of Alaska (NSA) sites over an 18-year period (January 2003 to December 2020), this study performs a fine-scale comparison of the climatological tropopause features between these two sites that are characterized by different climates. The static stability increases rapidly above the tropopause at both sites, indicating the widespread existence of a tropopause inversion layer. The structures of both the tropopause inversion layer and the stability transition layer are more obvious at NSA than at SGP, and the seasonal variation trends of the tropopause inversion layer and stability transition layer are distinctly different between the two sites. A fitting method was used to derive the fitted tropopause height and tropopause sharpness (λ). Although this fitting method may determine a secondary tropopause rather than the primary tropopause when multiple tropopause heights are identified on one radiosonde profile, the fitted tropopause heights generally agree well with the observed tropopause heights. Broad tropopause sharpness values (λ > 2 km) occur more frequently at SGP than at NSA, resulting in a greater average tropopause sharpness at SGP (1.0 km) than at NSA (0.6 km). Significant positive trends are exhibited by the tropopause heights over the two sites, with rates of increase of 23.7 ± 6.5 m yr−1 at SGP and 28.0 ± 4.0 m yr−1 at NSA during the study period.
Collapse
|
2
|
Homeyer CR, Bowman KP. A 22-Year Evaluation of Convection Reaching the Stratosphere Over the United States. JOURNAL OF GEOPHYSICAL RESEARCH. ATMOSPHERES : JGR 2021; 126:e2021JD034808. [PMID: 34322360 PMCID: PMC8312763 DOI: 10.1029/2021jd034808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 06/17/2021] [Indexed: 06/13/2023]
Abstract
Stratosphere-reaching moist convection can significantly alter the dynamics, chemistry, and climate of the Earth system. This study seeks to add to the emerging understanding of the frequency, depth, and stratospheric impact of such events using 22 years (1996-2017) of ground-based radar observations in the contiguous United States. While most prior studies identify such storms using the temperature lapse-rate tropopause (LRT) as a troposphere-stratosphere boundary, this study is the first to identify convection that reaches into stratospheric air below the LRT (tropopause depressions, excluding folds) as well. It is found that tropopause depression (TD) overshooting and LRT overshooting occur at similar frequency over the United States, with TD overshooting being more episodic in nature than LRT overshooting. TD overshooting is also found more often throughout the cooler months of the year, while LRT overshooting dominates all overshooting in the summer months. Stratospheric residence of overshoot material, as estimated using trajectory calculations driven by large-scale winds, suggests that the vast majority of TD overshoot material does not remain in the stratosphere within 5 days downstream and rarely impacts altitudes more than 1 km above the LRT. Conversely, the majority of LRT overshoot material remains in the stratosphere downstream and routinely impacts altitudes >1 and >2 km above the tropopause.
Collapse
Affiliation(s)
| | - Kenneth P Bowman
- Department of Atmospheric Sciences, Texas A&M University, College Station, TX, USA
| |
Collapse
|
3
|
Fix A, Steinebach F, Wirth M, Schäfler A, Ehret G. Development and application of an airborne differential absorption lidar for the simultaneous measurement of ozone and water vapor profiles in the tropopause region. APPLIED OPTICS 2019; 58:5892-5900. [PMID: 31503903 DOI: 10.1364/ao.58.005892] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 06/17/2019] [Indexed: 06/10/2023]
Abstract
A new, combined, lidar system has been developed that is able to simultaneously measure profiles of ozone and water vapor onboard aircraft. The concurrent measurement of these complementary trace species in the upper troposphere and lower stratosphere allows inferring exchange processes in the tropopause region. Whereas an advanced H2O differential absorption lidar at 935 nm has successfully been developed and extensively tested at DLR in the past, we describe here an amendment of this lidar by the addition of an ultraviolet (UV) channel to measure ozone. The transmitter of the ozone differential absorption lidar (DIAL) is based on a near-IR optical parametric oscillator that is frequency-converted into the UV spectral range by intracavity sum frequency mixing. Hereby, a continuous UV tuning range of ∼297-317 nm has been achieved. The average output power in this range is higher than 1 W corresponding to more than 10 mJ per pulse at a repetition rate of 100 Hz. The ozone DIAL system has been carefully characterized both on the ground and in flight. The first simultaneously measured two-dimensional cross-sections of ozone and water vapor in the upper troposphere and lower stratosphere have been recorded during the Wave-driven Isentropic Exchange (WISE) field campaign in 2017 demonstrating the high potential of this system for studying exchange processes in this region of the atmosphere.
Collapse
|
4
|
Lawrence ZD, Manney GL, Wargan K. Reanalysis intercomparisons of stratospheric polar processing diagnostics. ATMOSPHERIC CHEMISTRY AND PHYSICS 2018; 18:13547-13579. [PMID: 30581457 PMCID: PMC6299841 DOI: 10.5194/acp-18-13547-2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We compare herein polar processing diagnostics derived from the four most recent full-input reanalysis datasets: the National Centers for Environmental Prediction Climate Forecast System Reanalysis / Climate Forecast System, version 2 (CFSR/CFSv2), the European Centre for Medium-Range Weather Forecasts Interim Reanalysis (ERA-Interim), the Japanese Meteorological Agency's Japanese 55-year Reanalysis (JRA-55), and the National Aeronautics and Space Administration's Modern Era Retrospective-analysis for Research and Applications version 2 (MERRA-2). We focus on diagnostics based on temperatures and potential vorticity (PV) in the lower to middle stratosphere that are related to formation of polar stratospheric clouds (PSCs), chlorine activation, and the strength, size, and longevity of the stratospheric polar vortex. Polar minimum temperatures (Tmin) and the area of regions having temperatures below PSC formation thresholds (APSC) show large persistent differences between the reanalyses, especially in the southern hemisphere (SH), for years prior to 1999. Average absolute differences of the reanalyses from the reanalysis ensemble mean (REM) in Tmin are as large as 3 K at some levels in the SH (1.5 K in the NH), and absolute differences of reanalysis APSC from the REM up to 1.5% of a hemisphere (0.75% of a hemisphere in the NH). After 1999, the reanalyses converge toward better agreement in both hemispheres, dramatically so in the SH: Average Tmin differences from the REM are generally less than 1 K in both hemispheres, and average APSC differences less than 0.3% of a hemisphere. The comparisons of diagnostics based on isentropic PV for assessing polar vortex characteristics, including maximum PV gradients (MPVG) and the area of the vortex in sunlight (or sunlit vortex area, SVA), show more complex behavior: SH MPVG showed convergence toward better agreement with the REM after 1999, while NH MPVG differences remained largely constant over time; differences in SVA remained relatively constant in both hemispheres. While the average differences from the REM are generally small for these vortex diagnostics, understanding such differences among the reanalyses is complicated by the need to use different methods to obtain vertically-resolved PV for the different reanalyses. We also evaluated other winter season summary diagnostics, including the winter mean volume of air below PSC thresholds, and vortex decay dates. For the volume of air below PSC thresholds, the reanalyses generally agree best in the SH, where relatively small interannual variability has led to many winter seasons with similar polar processing potential and duration, and thus low sensitivity to differences in meteorological conditions among the reanalyses. In contrast, the large interannual variability of NH winters has given rise to many seasons with marginal conditions that are more sensitive to reanalysis differences. For vortex decay dates, larger differences are seen in the SH than in the NH; in general the differences in decay dates among the reanalyses follow from persistent differences in their vortex areas. Our results indicate that the transition from the reanalyses assimilating Tiros Operational Vertical Sounder (TOVS) data to Advanced TOVS and other data around 1998 - 2000 resulted in a profound improvement in the agreement of the temperature diagnostics presented (especially in the SH) and to a lesser extent the agreement of the vortex diagnostics. We present several recommendations for using reanalyses in polar processing studies, particularly related to the sensitivity to changes in data inputs and assimilation. Because of these sensitivities, we urge great caution for studies aiming to assess trends derived from reanalysis temperatures. We also argue that one of the best ways to assess the sensitivity of scientific results on polar processing is to use multiple reanalysis datasets.
Collapse
Affiliation(s)
- Zachary D Lawrence
- New Mexico Institute of Mining and Technology, Socorro, NM USA
- NorthWest Research Associates, Socorro, NM USA
| | - Gloria L Manney
- NorthWest Research Associates, Socorro, NM USA
- New Mexico Institute of Mining and Technology, Socorro, NM USA
| | - Krzysztof Wargan
- NASA/Goddard Space Flight Center, Greenbelt, MD USA
- Science Systems and Applications Inc., Lanham, MD, USA
| |
Collapse
|
5
|
Langille JA, Solheim B, Bourassa A, Degenstein D, Brown S, Shepherd GG. Measurement of water vapor using an imaging field-widened spatial heterodyne spectrometer. APPLIED OPTICS 2017; 56:4297-4308. [PMID: 29047854 DOI: 10.1364/ao.56.004297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Spatial heterodyne spectroscopy (SHS) has been successfully applied to measure variations in water vapor pressure in the lab. An imaging system is combined with a monolithic field-widened SHS to observe a white-light source through a 1 m length water vapor cell that is designed to produce predictable variations in the water vapor pressure. The performance of the spectrometer design is examined by comparing spectra simulated using a radiative transfer model to observed spectra at several cell pressures. The intended application of the instrument to vertically resolve the water vapor profile in the upper troposphere and lower stratosphere using limb-scattered radiation in a vibrational band of water (1363-1366 nm) is also introduced.
Collapse
|
6
|
Kunz A, Pan LL, Konopka P, Kinnison DE, Tilmes S. Chemical and dynamical discontinuity at the extratropical tropopause based on START08 and WACCM analyses. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd016686] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. Kunz
- Institut für Energie- und Klimaforschung: Stratosphäre, Forschungszentrum Jülich; Jülich Germany
- National Center for Atmospheric Research; Boulder Colorado USA
| | - L. L. Pan
- National Center for Atmospheric Research; Boulder Colorado USA
| | - P. Konopka
- Institut für Energie- und Klimaforschung: Stratosphäre, Forschungszentrum Jülich; Jülich Germany
| | - D. E. Kinnison
- National Center for Atmospheric Research; Boulder Colorado USA
| | - S. Tilmes
- National Center for Atmospheric Research; Boulder Colorado USA
| |
Collapse
|
7
|
Santee ML, Manney GL, Livesey NJ, Froidevaux L, Schwartz MJ, Read WG. Trace gas evolution in the lowermost stratosphere from Aura Microwave Limb Sounder measurements. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd015590] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
8
|
Whitt DB, Jacobson MZ, Wilkerson JT, Naiman AD, Lele SK. Vertical mixing of commercial aviation emissions from cruise altitude to the surface. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd015532] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
9
|
Vogel B, Pan LL, Konopka P, Günther G, Müller R, Hall W, Campos T, Pollack I, Weinheimer A, Wei J, Atlas EL, Bowman KP. Transport pathways and signatures of mixing in the extratropical tropopause region derived from Lagrangian model simulations. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014876] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
10
|
Schmidt T, Cammas JP, Smit HGJ, Heise S, Wickert J, Haser A. Observational characteristics of the tropopause inversion layer derived from CHAMP/GRACE radio occultations and MOZAIC aircraft data. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd014284] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- T. Schmidt
- Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences; Potsdam Germany
| | - J.-P. Cammas
- Laboratoire d'Aerologie; Observatoire Midi-Pyrénées, CNRS; Toulouse France
| | - H. G. J. Smit
- Institute for Energy and Climate Research: Troposphere; Research Centre Jülich; Jülich Germany
| | - S. Heise
- Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences; Potsdam Germany
| | - J. Wickert
- Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences; Potsdam Germany
| | - A. Haser
- Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences; Potsdam Germany
| |
Collapse
|
11
|
Hegglin MI, Gettelman A, Hoor P, Krichevsky R, Manney GL, Pan LL, Son SW, Stiller G, Tilmes S, Walker KA, Eyring V, Shepherd TG, Waugh D, Akiyoshi H, Añel JA, Austin J, Baumgaertner A, Bekki S, Braesicke P, Brühl C, Butchart N, Chipperfield M, Dameris M, Dhomse S, Frith S, Garny H, Hardiman SC, Jöckel P, Kinnison DE, Lamarque JF, Mancini E, Michou M, Morgenstern O, Nakamura T, Olivié D, Pawson S, Pitari G, Plummer DA, Pyle JA, Rozanov E, Scinocca JF, Shibata K, Smale D, Teyssèdre H, Tian W, Yamashita Y. Multimodel assessment of the upper troposphere and lower stratosphere: Extratropics. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2010jd013884] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
12
|
Sprung D, Zahn A. Acetone in the upper troposphere/lowermost stratosphere measured by the CARIBIC passenger aircraft: Distribution, seasonal cycle, and variability. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd012099] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
13
|
Tilmes S, Pan LL, Hoor P, Atlas E, Avery MA, Campos T, Christensen LE, Diskin GS, Gao RS, Herman RL, Hintsa EJ, Loewenstein M, Lopez J, Paige ME, Pittman JV, Podolske JR, Proffitt MR, Sachse GW, Schiller C, Schlager H, Smith J, Spelten N, Webster C, Weinheimer A, Zondlo MA. An aircraft-based upper troposphere lower stratosphere O3, CO, and H2O climatology for the Northern Hemisphere. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd012731] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
14
|
Homeyer CR, Bowman KP, Pan LL. Extratropical tropopause transition layer characteristics from high-resolution sounding data. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013664] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
15
|
Kunz A, Konopka P, Müller R, Pan LL, Schiller C, Rohrer F. High static stability in the mixing layer above the extratropical tropopause. ACTA ACUST UNITED AC 2009. [DOI: 10.1029/2009jd011840] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|