Articles | Volume 13, issue 6
https://doi.org/10.5194/acp-13-3121-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-13-3121-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
15 Mar 2013
Research article |
| 15 Mar 2013
High resolution VHF radar measurements of tropopause structure and variability at Davis, Antarctica (69° S, 78° E)
S. P. Alexander
Australian Antarctic Division, Kingston, Tasmania, Australia
D. J. Murphy
Australian Antarctic Division, Kingston, Tasmania, Australia
A. R. Klekociuk
Australian Antarctic Division, Kingston, Tasmania, Australia
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EGUsphere, https://doi.org/10.5194/egusphere-2024-3125, https://doi.org/10.5194/egusphere-2024-3125, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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In this paper, we use ground-based observations to evaluate a climate model and a satellite product in simulating surface radiation and investigate how radiation biases are influenced by cloud properties over the Southern Ocean. We find that significant radiation biases exist in both the model and satellite. The cloud fraction and cloud occurrence play an important role in affecting radiation biases. We suggest further development for the model and satellite using ground-based observations.
McKenna W. Stanford, Ann M. Fridlind, Israel Silber, Andrew S. Ackerman, Greg Cesana, Johannes Mülmenstädt, Alain Protat, Simon Alexander, and Adrian McDonald
Atmos. Chem. Phys., 23, 9037–9069, https://doi.org/10.5194/acp-23-9037-2023, https://doi.org/10.5194/acp-23-9037-2023, 2023
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Clouds play an important role in the Earth’s climate system as they modulate the amount of radiation that either reaches the surface or is reflected back to space. This study demonstrates an approach to robustly evaluate surface-based observations against a large-scale model. We find that the large-scale model precipitates too infrequently relative to observations, contrary to literature documentation suggesting otherwise based on satellite measurements.
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Atmos. Chem. Phys., 23, 5735–5762, https://doi.org/10.5194/acp-23-5735-2023, https://doi.org/10.5194/acp-23-5735-2023, 2023
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Ice-nucleating particles (INPs) play an important role in cloud processes and associated precipitation. Yet, INPs are not accurately represented in climate models. This study attempts to uncover these gaps by comparing model-simulated INP concentrations against field campaign measurements in the SO for an entire year, 2017–2018. Differences in INP concentrations and variability between the model and observations have major implications for modeling cloud properties in high latitudes.
Peter Kuma, Adrian J. McDonald, Olaf Morgenstern, Simon P. Alexander, John J. Cassano, Sally Garrett, Jamie Halla, Sean Hartery, Mike J. Harvey, Simon Parsons, Graeme Plank, Vidya Varma, and Jonny Williams
Atmos. Chem. Phys., 20, 6607–6630, https://doi.org/10.5194/acp-20-6607-2020, https://doi.org/10.5194/acp-20-6607-2020, 2020
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We evaluate clouds over the Southern Ocean in the climate model HadGEM3 and reanalysis MERRA-2 using ship-based ceilometer and radiosonde observations. We find the models underestimate cloud cover by 18–25 %, with clouds below 2 km dominant in reality but lacking in the models. We find a strong link between clouds, atmospheric stability and sea surface temperature in observations but not in the models, implying that sub-grid processes do not generate enough cloud in response to these conditions.
Jesse W. Greenslade, Simon P. Alexander, Robyn Schofield, Jenny A. Fisher, and Andrew K. Klekociuk
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Sonya L. Fiddes, Matthew T. Woodhouse, Marc D. Mallet, Liam Lamprey, Ruhi S. Humphries, Alain Protat, Simon P. Alexander, Hakase Hayashida, Samuel G. Putland, Branka Miljevic, and Robyn Schofield
EGUsphere, https://doi.org/10.5194/egusphere-2024-3125, https://doi.org/10.5194/egusphere-2024-3125, 2024
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The interaction between natural marine aerosols, clouds and radiation in the Southern Ocean is a major source of uncertainty in climate models. We evaluate the Australian climate model using aerosol observations and find it underestimates aerosol number often by over 50 %. Model changes were tested to improve aerosol concentrations, but some of our changes had severe negative effects on the larger climate system, highlighting issues in aerosol-cloud interaction modelling.
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Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2024-13, https://doi.org/10.5194/angeo-2024-13, 2024
Revised manuscript under review for ANGEO
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Gunter Stober, Sharon L. Vadas, Erich Becker, Alan Liu, Alexander Kozlovsky, Diego Janches, Zishun Qiao, Witali Krochin, Guochun Shi, Wen Yi, Jie Zeng, Peter Brown, Denis Vida, Neil Hindley, Christoph Jacobi, Damian Murphy, Ricardo Buriti, Vania Andrioli, Paulo Batista, John Marino, Scott Palo, Denise Thorsen, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Kathrin Baumgarten, Johan Kero, Evgenia Belova, Nicholas Mitchell, Tracy Moffat-Griffin, and Na Li
Atmos. Chem. Phys., 24, 4851–4873, https://doi.org/10.5194/acp-24-4851-2024, https://doi.org/10.5194/acp-24-4851-2024, 2024
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On 15 January 2022, the Hunga Tonga-Hunga Ha‘apai volcano exploded in a vigorous eruption, causing many atmospheric phenomena reaching from the surface up to space. In this study, we investigate how the mesospheric winds were affected by the volcanogenic gravity waves and estimated their propagation direction and speed. The interplay between model and observations permits us to gain new insights into the vertical coupling through atmospheric gravity waves.
Sonya L. Fiddes, Marc D. Mallet, Alain Protat, Matthew T. Woodhouse, Simon P. Alexander, and Kalli Furtado
Geosci. Model Dev., 17, 2641–2662, https://doi.org/10.5194/gmd-17-2641-2024, https://doi.org/10.5194/gmd-17-2641-2024, 2024
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Ralph Latteck and Damian J. Murphy
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This paper gives an overview of continuous measurements of polar mesophere summer echoes (PMSE) by VHF radars at Andøya (69° N) and Davis (69° S). PMSE signal strengths are of the same order of magnitude; significantly fewer PMSE were observed in the Southern than the Northern Hemisphere. Compared to Andøya, the PMSE season over Davis starts ~7 d later and ends 9 d earlier; PMSE occur less frequently but with greater seasonal/diurnal occurrence variability, reaching higher peak altitudes.
Zhangcheng Pei, Sonya L. Fiddes, W. John R. French, Simon P. Alexander, Marc D. Mallet, Peter Kuma, and Adrian McDonald
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In this paper, we use ground-based observations to evaluate a climate model and a satellite product in simulating surface radiation and investigate how radiation biases are influenced by cloud properties over the Southern Ocean. We find that significant radiation biases exist in both the model and satellite. The cloud fraction and cloud occurrence play an important role in affecting radiation biases. We suggest further development for the model and satellite using ground-based observations.
McKenna W. Stanford, Ann M. Fridlind, Israel Silber, Andrew S. Ackerman, Greg Cesana, Johannes Mülmenstädt, Alain Protat, Simon Alexander, and Adrian McDonald
Atmos. Chem. Phys., 23, 9037–9069, https://doi.org/10.5194/acp-23-9037-2023, https://doi.org/10.5194/acp-23-9037-2023, 2023
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Aishwarya Raman, Thomas Hill, Paul J. DeMott, Balwinder Singh, Kai Zhang, Po-Lun Ma, Mingxuan Wu, Hailong Wang, Simon P. Alexander, and Susannah M. Burrows
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Ice-nucleating particles (INPs) play an important role in cloud processes and associated precipitation. Yet, INPs are not accurately represented in climate models. This study attempts to uncover these gaps by comparing model-simulated INP concentrations against field campaign measurements in the SO for an entire year, 2017–2018. Differences in INP concentrations and variability between the model and observations have major implications for modeling cloud properties in high latitudes.
Ruhi S. Humphries, Melita D. Keywood, Jason P. Ward, James Harnwell, Simon P. Alexander, Andrew R. Klekociuk, Keiichiro Hara, Ian M. McRobert, Alain Protat, Joel Alroe, Luke T. Cravigan, Branka Miljevic, Zoran D. Ristovski, Robyn Schofield, Stephen R. Wilson, Connor J. Flynn, Gourihar R. Kulkarni, Gerald G. Mace, Greg M. McFarquhar, Scott D. Chambers, Alastair G. Williams, and Alan D. Griffiths
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Observations of aerosols in pristine regions are rare but are vital to constraining the natural baseline from which climate simulations are calculated. Here we present recent seasonal observations of aerosols from the Southern Ocean and contrast them with measurements from Antarctica, Australia and regionally relevant voyages. Strong seasonal cycles persist, but striking differences occur at different latitudes. This study highlights the need for more long-term observations in remote regions.
Adrien Guyot, Alain Protat, Simon P. Alexander, Andrew R. Klekociuk, Peter Kuma, and Adrian McDonald
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Ceilometers are instruments that are widely deployed as part of operational networks. They are usually not able to detect cloud phase. Here, we propose an evaluation of various methods to detect supercooled liquid water with ceilometer observations, using an extensive dataset from Davis, Antarctica. Our results highlight the possibility for ceilometers to detect supercooled liquid water in clouds.
Jill Brouwer, Alexander D. Fraser, Damian J. Murphy, Pat Wongpan, Alberto Alberello, Alison Kohout, Christopher Horvat, Simon Wotherspoon, Robert A. Massom, Jessica Cartwright, and Guy D. Williams
The Cryosphere, 16, 2325–2353, https://doi.org/10.5194/tc-16-2325-2022, https://doi.org/10.5194/tc-16-2325-2022, 2022
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Alexander D. Fraser, Robert A. Massom, Mark S. Handcock, Phillip Reid, Kay I. Ohshima, Marilyn N. Raphael, Jessica Cartwright, Andrew R. Klekociuk, Zhaohui Wang, and Richard Porter-Smith
The Cryosphere, 15, 5061–5077, https://doi.org/10.5194/tc-15-5061-2021, https://doi.org/10.5194/tc-15-5061-2021, 2021
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Landfast ice is sea ice that remains stationary by attaching to Antarctica's coastline and grounded icebergs. Although a variable feature, landfast ice exerts influence on key coastal processes involving pack ice, the ice sheet, ocean, and atmosphere and is of ecological importance. We present a first analysis of change in landfast ice over an 18-year period and quantify trends (−0.19 ± 0.18 % yr−1). This analysis forms a reference of landfast-ice extent and variability for use in other studies.
Camilla K. Crockart, Tessa R. Vance, Alexander D. Fraser, Nerilie J. Abram, Alison S. Criscitiello, Mark A. J. Curran, Vincent Favier, Ailie J. E. Gallant, Christoph Kittel, Helle A. Kjær, Andrew R. Klekociuk, Lenneke M. Jong, Andrew D. Moy, Christopher T. Plummer, Paul T. Vallelonga, Jonathan Wille, and Lingwei Zhang
Clim. Past, 17, 1795–1818, https://doi.org/10.5194/cp-17-1795-2021, https://doi.org/10.5194/cp-17-1795-2021, 2021
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We present preliminary analyses of the annual sea salt concentrations and snowfall accumulation in a new East Antarctic ice core, Mount Brown South. We compare this record with an updated Law Dome (Dome Summit South site) ice core record over the period 1975–2016. The Mount Brown South record preserves a stronger and inverse signal for the El Niño–Southern Oscillation (in austral winter and spring) compared to the Law Dome record (in summer).
William R. Hobbs, Andrew R. Klekociuk, and Yuhang Pan
Atmos. Chem. Phys., 20, 14757–14768, https://doi.org/10.5194/acp-20-14757-2020, https://doi.org/10.5194/acp-20-14757-2020, 2020
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Reanalysis products are an invaluable tool for representing variability and long-term trends in regions with limited in situ data. However, validation of these products is difficult because of that lack of station data. Here we present a novel assessment of eight reanalyses over the polar Southern Ocean, leveraging the close relationship between trends in sea ice cover and surface air temperature, that provides clear guidance on the most reliable product for Antarctic research.
W. John R. French, Andrew R. Klekociuk, and Frank J. Mulligan
Atmos. Chem. Phys., 20, 8691–8708, https://doi.org/10.5194/acp-20-8691-2020, https://doi.org/10.5194/acp-20-8691-2020, 2020
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We explore a quasi-quadrennial oscillation (QQO; 3–4 K amplitude, ~ 4-year period) in mesopause region temperatures observed in 24 years of hydroxyl airglow measurements over Davis, Antarctica (68° S, 78° E). Correlation and composite analysis using meteorological reanalysis and satellite data reveals complex patterns on the QQO timescale in both hemispheres. Modulation of the meridional circulation, linked to the propagation of gravity waves, plays a significant role in producing the QQO response.
Peter Kuma, Adrian J. McDonald, Olaf Morgenstern, Simon P. Alexander, John J. Cassano, Sally Garrett, Jamie Halla, Sean Hartery, Mike J. Harvey, Simon Parsons, Graeme Plank, Vidya Varma, and Jonny Williams
Atmos. Chem. Phys., 20, 6607–6630, https://doi.org/10.5194/acp-20-6607-2020, https://doi.org/10.5194/acp-20-6607-2020, 2020
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We evaluate clouds over the Southern Ocean in the climate model HadGEM3 and reanalysis MERRA-2 using ship-based ceilometer and radiosonde observations. We find the models underestimate cloud cover by 18–25 %, with clouds below 2 km dominant in reality but lacking in the models. We find a strong link between clouds, atmospheric stability and sea surface temperature in observations but not in the models, implying that sub-grid processes do not generate enough cloud in response to these conditions.
W. John R. French, Frank J. Mulligan, and Andrew R. Klekociuk
Atmos. Chem. Phys., 20, 6379–6394, https://doi.org/10.5194/acp-20-6379-2020, https://doi.org/10.5194/acp-20-6379-2020, 2020
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In this study, we analyse 24 years of atmospheric temperatures from the mesopause region (~87 km altitude) derived from ground-based spectrometer observations of hydroxyl airglow at Davis station, Antarctica (68° S, 78° E). These data are used to quantify the effect of the solar cycle and the long-term trend due to increasing greenhouse gas emissions on the atmosphere at this level. A record-low winter-average temperature is reported for 2018 and comparisons are made with satellite observations.
Julie M. Nicely, Bryan N. Duncan, Thomas F. Hanisco, Glenn M. Wolfe, Ross J. Salawitch, Makoto Deushi, Amund S. Haslerud, Patrick Jöckel, Béatrice Josse, Douglas E. Kinnison, Andrew Klekociuk, Michael E. Manyin, Virginie Marécal, Olaf Morgenstern, Lee T. Murray, Gunnar Myhre, Luke D. Oman, Giovanni Pitari, Andrea Pozzer, Ilaria Quaglia, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Kane Stone, Susan Strahan, Simone Tilmes, Holger Tost, Daniel M. Westervelt, and Guang Zeng
Atmos. Chem. Phys., 20, 1341–1361, https://doi.org/10.5194/acp-20-1341-2020, https://doi.org/10.5194/acp-20-1341-2020, 2020
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Differences in methane lifetime among global models are large and poorly understood. We use a neural network method and simulations from the Chemistry Climate Model Initiative to quantify the factors influencing methane lifetime spread among models and variations over time. UV photolysis, tropospheric ozone, and nitrogen oxides drive large model differences, while the same factors plus specific humidity contribute to a decreasing trend in methane lifetime between 1980 and 2015.
Yuke Wang, Valerii Shulga, Gennadi Milinevsky, Aleksey Patoka, Oleksandr Evtushevsky, Andrew Klekociuk, Wei Han, Asen Grytsai, Dmitry Shulga, Valery Myshenko, and Oleksandr Antyufeyev
Atmos. Chem. Phys., 19, 10303–10317, https://doi.org/10.5194/acp-19-10303-2019, https://doi.org/10.5194/acp-19-10303-2019, 2019
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The major sudden stratospheric warming (SSW) dramatically changed atmospheric conditions. This event is accompanied by a sharp increase in the polar stratosphere temperature, zonal wind reverse, and strong changes in the polar mesosphere. These changes affect even the midlatitude mesosphere, which is not widely covered by observations. Our newly installed microwave radiometer allowed for studying mesospheric zonal wind and CO variations to understand the SSW 2018 effects at midlatitudes.
Wen Yi, Xianghui Xue, Iain M. Reid, Damian J. Murphy, Chris M. Hall, Masaki Tsutsumi, Baiqi Ning, Guozhu Li, Robert A. Vincent, Jinsong Chen, Jianfei Wu, Tingdi Chen, and Xiankang Dou
Atmos. Chem. Phys., 19, 7567–7581, https://doi.org/10.5194/acp-19-7567-2019, https://doi.org/10.5194/acp-19-7567-2019, 2019
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The seasonal variations in the mesopause densities, especially with regard to its global structure, are still unclear. In this study, we report the climatology of the mesopause density estimated using multiyear observations from nine meteor radars from Arctic to Antarctic latitudes. The results reveal a significant AO and SAO in mesopause density, an asymmetry between the two polar regions and evidence of intraseasonal oscillations (ISOs), perhaps associated with the ISOs of the troposphere.
Sven Wilhelm, Gunter Stober, Vivien Matthias, Christoph Jacobi, and Damian J. Murphy
Ann. Geophys., 37, 1–14, https://doi.org/10.5194/angeo-37-1-2019, https://doi.org/10.5194/angeo-37-1-2019, 2019
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This study shows that the mesospheric winds are affected by an expansion–shrinking of the mesosphere and lower thermosphere that takes place due to changes in the intensity of the solar radiation, which affects the density within the atmosphere. On seasonal timescales, an increase in the neutral density occurs together with a decrease in the eastward-directed zonal wind. Further, even after removing the seasonal and the 11-year solar cycle variations, we show a connection between them.
Blanca Ayarzagüena, Lorenzo M. Polvani, Ulrike Langematz, Hideharu Akiyoshi, Slimane Bekki, Neal Butchart, Martin Dameris, Makoto Deushi, Steven C. Hardiman, Patrick Jöckel, Andrew Klekociuk, Marion Marchand, Martine Michou, Olaf Morgenstern, Fiona M. O'Connor, Luke D. Oman, David A. Plummer, Laura Revell, Eugene Rozanov, David Saint-Martin, John Scinocca, Andrea Stenke, Kane Stone, Yousuke Yamashita, Kohei Yoshida, and Guang Zeng
Atmos. Chem. Phys., 18, 11277–11287, https://doi.org/10.5194/acp-18-11277-2018, https://doi.org/10.5194/acp-18-11277-2018, 2018
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Stratospheric sudden warmings (SSWs) are natural major disruptions of the polar stratospheric circulation that also affect surface weather. In the literature there are conflicting claims as to whether SSWs will change in the future. The confusion comes from studies using different models and methods. Here we settle the question by analysing 12 models with a consistent methodology, to show that no robust changes in frequency and other features are expected over the 21st century.
Jesse W. Greenslade, Simon P. Alexander, Robyn Schofield, Jenny A. Fisher, and Andrew K. Klekociuk
Atmos. Chem. Phys., 17, 10269–10290, https://doi.org/10.5194/acp-17-10269-2017, https://doi.org/10.5194/acp-17-10269-2017, 2017
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An analysis of data from ozonesondes released at three southern oceanic sites shows the impact of stratospheric ozone in this region. Using a novel method of transport classification, this work estimates the seasonality and quantity of stratospherically sourced ozone. We find that ozone is transported most frequently in summer due to regional-scale low-pressure weather systems. We also estimate a stratospheric ozone source of 2.0–3.3 Tg/year over three Southern Ocean regions.
Chris S.~M. Turney, Andrew Klekociuk, Christopher J. Fogwill, Violette Zunz, Hugues Goosse, Claire L. Parkinson, Gilbert Compo, Matthew Lazzara, Linda Keller, Rob Allan, Jonathan G. Palmer, Graeme Clark, and Ezequiel Marzinelli
The Cryosphere Discuss., https://doi.org/10.5194/tc-2017-51, https://doi.org/10.5194/tc-2017-51, 2017
Revised manuscript not accepted
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We demonstrate that a mid-twentieth century decrease in geopotential height in the southwest Pacific marks a Rossby wave response to equatorial Pacific warming, leading to enhanced easterly airflow off George V Land. Our results suggest that in contrast to ozone hole-driven changes in the Amundsen Sea, the 1979–2015 increase in sea ice extent off George V Land may be in response to reduced northward Ekman drift and enhanced (near-coast) production as a consequence of low latitude forcing.
Iain M. Reid, Andrew J. Spargo, Jonathan M. Woithe, Andrew R. Klekociuk, Joel P. Younger, and Gulamabas G. Sivjee
Ann. Geophys., 35, 567–582, https://doi.org/10.5194/angeo-35-567-2017, https://doi.org/10.5194/angeo-35-567-2017, 2017
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We measured temperatures in the atmosphere at heights near 90 km using nightglow emissions and compared them with satellite measurements and with measurements made with a meteor radar. We found good agreement between the techniques, which improved when we used the meteor radar and satellite data to measure densities at two heights separated by about 10 km to estimate the nightglow emission height.
Asen Grytsai, Andrew Klekociuk, Gennadi Milinevsky, Oleksandr Evtushevsky, and Kane Stone
Atmos. Chem. Phys., 17, 1741–1758, https://doi.org/10.5194/acp-17-1741-2017, https://doi.org/10.5194/acp-17-1741-2017, 2017
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Twenty years ago we discovered that the ozone hole shape is asymmetric. This asymmetry is minimum over the Weddell Sea region and maximum over the Ross Sea area. Later we detected that the position of the ozone minimum is shifting east. We have continued to follow this event, and a couple years ago we revealed that the shift is slowing down and starting to move back. We connect all this movement with ozone hole increase; since 2000 the ozone layer has been stabilizing and recently recovering.
Kane A. Stone, Olaf Morgenstern, David J. Karoly, Andrew R. Klekociuk, W. John French, N. Luke Abraham, and Robyn Schofield
Atmos. Chem. Phys., 16, 2401–2415, https://doi.org/10.5194/acp-16-2401-2016, https://doi.org/10.5194/acp-16-2401-2016, 2016
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This paper describes the set-up and evaluation of the Australian Community Climate and Earth System Simulator – chemistry-climate model.
Emphasis is placed on the Antarctic ozone hole, which is very important considering its role modulating Southern Hemisphere surface climate. While the model simulates the global distribution of ozone well, there is a disparity in the vertical location of springtime ozone depletion over Antarctica, highlighting important areas for future development.
Emphasis is placed on the Antarctic ozone hole, which is very important considering its role modulating Southern Hemisphere surface climate. While the model simulates the global distribution of ozone well, there is a disparity in the vertical location of springtime ozone depletion over Antarctica, highlighting important areas for future development.
R. S. Humphries, A. R. Klekociuk, R. Schofield, M. Keywood, J. Ward, and S. R. Wilson
Atmos. Chem. Phys., 16, 2185–2206, https://doi.org/10.5194/acp-16-2185-2016, https://doi.org/10.5194/acp-16-2185-2016, 2016
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This work represents the first observational study of atmospheric sub-micron aerosols in the East Antarctic pack ice region and found springtime aerosol concentrations were higher than any observed elsewhere in the Antarctic and Southern Ocean region. Further analysis suggested these aerosols formed in the Antarctic free troposphere. Their subsequent transport to the Southern Ocean, as suggest by trajectory analyses, could help to reduce the discrepancy in the radiative budget in the region.
C. S. M. Turney, C. J. Fogwill, A. R. Klekociuk, T. D. van Ommen, M. A. J. Curran, A. D. Moy, and J. G. Palmer
The Cryosphere, 9, 2405–2415, https://doi.org/10.5194/tc-9-2405-2015, https://doi.org/10.5194/tc-9-2405-2015, 2015
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Recent trends in ocean circulation, sea ice and climate over the Southern Ocean and Antarctica are highly complex. Here we report a new snow core from the South Pole alongside reanalysis of 20th century global atmospheric circulation. We demonstrate for the first time that atmospheric pressure anomalies in the mid-latitudes act as "gatekeepers" to meridional exchange over continental Antarctica, modulated by the tropical Pacific, with potentially significant impacts on surface mass balance.
R. S. Humphries, R. Schofield, M. D. Keywood, J. Ward, J. R. Pierce, C. M. Gionfriddo, M. T. Tate, D. P. Krabbenhoft, I. E. Galbally, S. B. Molloy, A. R. Klekociuk, P. V. Johnston, K. Kreher, A. J. Thomas, A. D. Robinson, N. R. P. Harris, R. Johnson, and S. R. Wilson
Atmos. Chem. Phys., 15, 13339–13364, https://doi.org/10.5194/acp-15-13339-2015, https://doi.org/10.5194/acp-15-13339-2015, 2015
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An atmospheric new particle formation event that was observed in the pristine East Antarctic pack ice during a springtime voyage in 2012 is characterised in terms of formation and growth rates. Known nucleation mechanisms (e.g. those involving sulfate, iodine and organics) were unable to explain observations; however, correlations with total gaseous mercury were found, leading to the suggestion of a possible mercury-driven nucleation mechanism not previously described.
J. M. Siddaway, S. V. Petelina, D. J. Karoly, A. R. Klekociuk, and R. J. Dargaville
Atmos. Chem. Phys., 13, 4413–4427, https://doi.org/10.5194/acp-13-4413-2013, https://doi.org/10.5194/acp-13-4413-2013, 2013
Related subject area
Subject: Dynamics | Research Activity: Remote Sensing | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
The Paris low-level jet during PANAME 2022 and its impact on the summertime urban heat island
An air quality and boundary layer dynamics analysis of the Los Angeles basin area during the Southwest Urban NOx and VOCs Experiment (SUNVEx)
Turbulent Energy Budget Analysis Based on Coherent Wind Lidar Observations
Equatorial waves resolved by balloon-borne Global Navigation Satellite System radio occultation in the Strateole-2 campaign
Wind lidars reveal turbulence transport mechanism in the wake of a tree
On the role of aerosol radiative effect in the wet season onset timing over the Congo rainforest during boreal autumn
Study of the seasonal variation in Aeolus wind product performance over China using ERA5 and radiosonde data
Measurement report: characteristics of clear-day convective boundary layer and associated entrainment zone as observed by a ground-based polarization lidar over Wuhan (30.5° N, 114.4° E)
Technical note: First comparison of wind observations from ESA's satellite mission Aeolus and ground-based radar wind profiler network of China
Assessment of vertical air motion among reanalyses and qualitative comparison with very-high-frequency radar measurements over two tropical stations
Asian summer monsoon anticyclone: trends and variability
Very high stratospheric influence observed in the free troposphere over the northern Alps – just a local phenomenon?
Long-lived high-frequency gravity waves in the atmospheric boundary layer: observations and simulations
Variability of temperature and ozone in the upper troposphere and lower stratosphere from multi-satellite observations and reanalysis data
Indications for a potential synchronization between the phase evolution of the Madden–Julian oscillation and the solar 27-day cycle
Mesoscale fine structure of a tropopause fold over mountains
Tropical convection regimes in climate models: evaluation with satellite observations
Wave modulation of the extratropical tropopause inversion layer
Planetary boundary layer height from CALIOP compared to radiosonde over China
Exploring atmospheric blocking with GPS radio occultation observations
Upper tropospheric water vapour variability at high latitudes – Part 1: Influence of the annular modes
Mixing layer height and its implications for air pollution over Beijing, China
Effect of tropical cyclones on the tropical tropopause parameters observed using COSMIC GPS RO data
New fire diurnal cycle characterizations to improve fire radiative energy assessments made from MODIS observations
Tropospheric ozone variability in the tropics from ENSO to MJO and shorter timescales
A comprehensive investigation on afternoon transition of the atmospheric boundary layer over a tropical rural site
Characterization of thermal structure and conditions for overshooting of tropical and extratropical cyclones with GPS radio occultation
Spatiotemporal variability of water vapor investigated using lidar and FTIR vertical soundings above the Zugspitze
Temperature profiling of the atmospheric boundary layer with rotational Raman lidar during the HD(CP)2 Observational Prototype Experiment
Determination and climatology of the planetary boundary layer height above the Swiss plateau by in situ and remote sensing measurements as well as by the COSMO-2 model
Comparison of the diurnal variations of warm-season precipitation for East Asia vs. North America downstream of the Tibetan Plateau vs. the Rocky Mountains
How stratospheric are deep stratospheric intrusions?
Impact of tropical land convection on the water vapour budget in the tropical tropopause layer
The thermodynamic state of the Arctic atmosphere observed by AIRS: comparisons during the record minimum sea ice extents of 2007 and 2012
Measurements of the movement of the jet streams at mid-latitudes, in the Northern and Southern Hemispheres, 1979 to 2010
Continuous detection and characterization of the Sea Breeze in clear sky conditions using Meteosat Second Generation
Thermal structure of intense convective clouds derived from GPS radio occultations
Advances and limitations of atmospheric boundary layer observations with GPS occultation over southeast Pacific Ocean
Teleconnection between Australian winter temperature and Indian summer monsoon rainfall
First results from the GPS atmosphere sounding experiment TOR aboard the TerraSAR-X satellite
Updraft and downdraft characterization with Doppler lidar: cloud-free versus cumuli-topped mixed layer
Remote sensing of the tropical rain forest boundary layer using pulsed Doppler lidar
A new ENSO index derived from satellite measurements of column ozone
Turbulence associated with mountain waves over Northern Scandinavia – a case study using the ESRAD VHF radar and the WRF mesoscale model
Jonnathan Céspedes, Simone Kotthaus, Jana Preissler, Clément Toupoint, Ludovic Thobois, Marc-Antoine Drouin, Jean-Charles Dupont, Aurélien Faucheux, and Martial Haeffelin
Atmos. Chem. Phys., 24, 11477–11496, https://doi.org/10.5194/acp-24-11477-2024, https://doi.org/10.5194/acp-24-11477-2024, 2024
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The low-level jet (LLJ) is common in Paris during summer. The LLJ core height and speed significantly influence vertical mixing in the urban boundary layer, which affects air temperature variations between the urban canopy layer and surrounding rural areas, determining the urban heat island (UHI) intensity. This study highlights the importance of wind profile observations for understanding urban boundary layer dynamics and near-surface atmospheric conditions relevant to health.
Edward J. Strobach, Sunil Baidar, Brian J. Carroll, Steven S. Brown, Kristen Zuraski, Matthew Coggon, Chelsea E. Stockwell, Lu Xu, Yelena L. Pichugina, W. Alan Brewer, Carsten Warneke, Jeff Peischl, Jessica Gilman, Brandi McCarty, Maxwell Holloway, and Richard Marchbanks
Atmos. Chem. Phys., 24, 9277–9307, https://doi.org/10.5194/acp-24-9277-2024, https://doi.org/10.5194/acp-24-9277-2024, 2024
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Large-scale weather patterns are isolated from local patterns to study the impact that different weather scales have on air quality measurements. While impacts from large-scale meteorology were evaluated by separating ozone (O3) exceedance (>70 ppb) and non-exceedance (<70 ppb) days, we developed a technique that allows direct comparisons of small temporal variations between chemical and dynamics measurements under rapid dynamical transitions.
Jinhong Xian, Zongxu Qiu, Hongyan Luo, Yuanyuan Hu, Xiaoling Lin, Chao Lu, Yan Yang, Honglong Yang, and Ning Zhang
EGUsphere, https://doi.org/10.5194/egusphere-2024-2163, https://doi.org/10.5194/egusphere-2024-2163, 2024
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The existing methods for observing turbulent kinetic energy budget term can only rely on ground-based tower. We have developed a new detection method that can directly observe and analyze the generation and dissipation mechanisms of turbulent energy at different heights in the vertical direction of the boundary layer. This research result will extend our study of turbulent kinetic energy budget terms from near ground to high altitude, providing a higher and more detailed perspective.
Bing Cao, Jennifer S. Haase, Michael J. Murphy, M. Joan Alexander, Martina Bramberger, and Albert Hertzog
Atmos. Chem. Phys., 22, 15379–15402, https://doi.org/10.5194/acp-22-15379-2022, https://doi.org/10.5194/acp-22-15379-2022, 2022
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Atmospheric waves that carry momentum from tropospheric weather systems into the equatorial stratosphere modify the winds there. The Strateole-2 2019 campaign launched long-duration stratospheric superpressure balloons to measure these equatorial waves. We deployed a GPS receiver on one of the balloons to measure atmospheric temperature profiles beneath the balloon. Temperature variations in the retrieved profiles show planetary-scale waves with a 20 d period and 3–4 d period waves.
Nikolas Angelou, Jakob Mann, and Ebba Dellwik
Atmos. Chem. Phys., 22, 2255–2268, https://doi.org/10.5194/acp-22-2255-2022, https://doi.org/10.5194/acp-22-2255-2022, 2022
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In this study we use state-of-the-art scanning wind lidars to investigate the wind field in the near-wake region of a mature, open-grown tree. Our measurements provide for the first time a picture of the mean and the turbulent spatial fluctuations in the flow in the wake of a tree in its natural environment. Our observations support the hypothesis that even simple models can realistically simulate the turbulent fluctuations in the wake and thus predict the effect of trees in flow models.
Sudip Chakraborty, Jonathon H. Jiang, Hui Su, and Rong Fu
Atmos. Chem. Phys., 21, 12855–12866, https://doi.org/10.5194/acp-21-12855-2021, https://doi.org/10.5194/acp-21-12855-2021, 2021
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Boreal autumn is the main wet season over the Congo basin. Thus, changes in its onset date have a significant impact on the rainforest. This study provides compelling evidence that the cooling effect of aerosols modifies the timing and strength of the southern African easterly jet that is central to the boreal autumn wet season over the Congo rainforest. A higher boreal summer aerosol concentration is positively correlated with the boreal autumn wet season onset timing.
Siying Chen, Rongzheng Cao, Yixuan Xie, Yinchao Zhang, Wangshu Tan, He Chen, Pan Guo, and Peitao Zhao
Atmos. Chem. Phys., 21, 11489–11504, https://doi.org/10.5194/acp-21-11489-2021, https://doi.org/10.5194/acp-21-11489-2021, 2021
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In this study, the seasonal variation in Aeolus wind product performance over China is analyzed by using L-band radiosonde detection data and ERA5 reanalysis data. The results show that the Aeolus wind product performance is affected by seasonal factors, which may be caused by seasonal changes in wind direction and cloud distribution.
Fuchao Liu, Fan Yi, Zhenping Yin, Yunpeng Zhang, Yun He, and Yang Yi
Atmos. Chem. Phys., 21, 2981–2998, https://doi.org/10.5194/acp-21-2981-2021, https://doi.org/10.5194/acp-21-2981-2021, 2021
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Using high-resolution lidar measurements, this process-based study reveals that the clear-day convective boundary layer evolves in four distinct stages differing in depth growth rate and depth fluctuation magnitudes. The accompanying entrainment zone thickness (EZT) shows a discrepancy in statistical mean and standard deviation for different seasons and developing stages. Common EZT characteristics also exist. These findings help us understand the atmospheric boundary layer evolution.
Jianping Guo, Boming Liu, Wei Gong, Lijuan Shi, Yong Zhang, Yingying Ma, Jian Zhang, Tianmeng Chen, Kaixu Bai, Ad Stoffelen, Gerrit de Leeuw, and Xiaofeng Xu
Atmos. Chem. Phys., 21, 2945–2958, https://doi.org/10.5194/acp-21-2945-2021, https://doi.org/10.5194/acp-21-2945-2021, 2021
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Vertical wind profiles are crucial to a wide range of atmospheric disciplines. Aeolus is the first satellite mission to directly observe wind profile information on a global scale. However, Aeolus wind products over China have thus far not been evaluated by in situ comparison. This work is expected to let the public and science community better know the Aeolus wind products and to encourage use of these valuable data in future research and applications.
Kizhathur Narasimhan Uma, Siddarth Shankar Das, Madineni Venkat Ratnam, and Kuniyil Viswanathan Suneeth
Atmos. Chem. Phys., 21, 2083–2103, https://doi.org/10.5194/acp-21-2083-2021, https://doi.org/10.5194/acp-21-2083-2021, 2021
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Reanalysis data of vertical wind (w) are widely used by the atmospheric community to determine various calculations of atmospheric circulations, diabatic heating, convection, etc. There are no studies that assess the available reanalysis data with respect to observations. The present study assesses for the first time all the reanalysis w by comparing it with 20 years of radar data from Gadanki and Kototabang and shows that downdrafts and peaks in the updrafts are not produced in the reanalyses.
Ghouse Basha, M. Venkat Ratnam, and Pangaluru Kishore
Atmos. Chem. Phys., 20, 6789–6801, https://doi.org/10.5194/acp-20-6789-2020, https://doi.org/10.5194/acp-20-6789-2020, 2020
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This study explores the variability of the Asian summer monsoon anticyclone (ASMA) spatial variability and trends using long-term observational and reanalysis data sets. The decadal variability of the anticyclone is very large at the edges compared with the core region. We propose that the transport process over the Tibetan Plateau and the Indian region is significant in active monsoon, strong monsoon and strong La Niña years. Thus, different phases of the monsoon are important in UTLS analyses.
Thomas Trickl, Hannes Vogelmann, Ludwig Ries, and Michael Sprenger
Atmos. Chem. Phys., 20, 243–266, https://doi.org/10.5194/acp-20-243-2020, https://doi.org/10.5194/acp-20-243-2020, 2020
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Ozone transfer from the stratosphere to the troposphere seems to to have grown over the past decade, parallel to global warming. Lidar measurements, carried out in Garmisch-Partenkirchen, Germany, between 2007 and 2016 show a considerable stratospheric influence in the free troposphere over these sites, with observations of stratospheric layers in the troposphere on 84 % of the measurement days. This high fraction is almost reached also in North America, but frequently not throughout the year.
Mingjiao Jia, Jinlong Yuan, Chong Wang, Haiyun Xia, Yunbin Wu, Lijie Zhao, Tianwen Wei, Jianfei Wu, Lu Wang, Sheng-Yang Gu, Liqun Liu, Dachun Lu, Rulong Chen, Xianghui Xue, and Xiankang Dou
Atmos. Chem. Phys., 19, 15431–15446, https://doi.org/10.5194/acp-19-15431-2019, https://doi.org/10.5194/acp-19-15431-2019, 2019
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Gravitational waves (GWs) with periods ranging from 10 to 30 min over 10 h and 20 wave cycles are detected within a 2 km height in the atmospheric boundary layer (ABL) by a coherent Doppler wind lidar. Observations and computational fluid dynamics (CFD) simulations lead to a conclusion that the GWs are excited by the wind shear of a low-level jet under the condition of light horizontal wind. The GWs are trapped in the ABL due to a combination of thermal and Doppler ducts.
Ming Shangguan, Wuke Wang, and Shuanggen Jin
Atmos. Chem. Phys., 19, 6659–6679, https://doi.org/10.5194/acp-19-6659-2019, https://doi.org/10.5194/acp-19-6659-2019, 2019
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A significant warming in the troposphere and cooling in the stratosphere are found in satellite measurements (2002–2017). The newest ERA5 data are first used for analyzing temperature and ozone trends in the UTLS and show the best quality compared to other reanalyses. According to model simulations, the temperature increase in the troposphere and ozone decrease in the NH stratosphere are mainly connected to a surface warming of the ocean and subsequent changes in atmospheric circulation.
Christoph G. Hoffmann and Christian von Savigny
Atmos. Chem. Phys., 19, 4235–4256, https://doi.org/10.5194/acp-19-4235-2019, https://doi.org/10.5194/acp-19-4235-2019, 2019
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We examine a possible statistical linkage between atmospheric variability in the tropical troposphere on the intraseasonal timescale, which is known as Madden–Julian oscillation, and known variability of the solar radiation with a period of 27 days. This helps to understand tropospheric variability in more detail, which is generally of interest, e.g., for weather forecasting. We find indications for such a linkage; however, more research has to be conducted for an unambiguous attribution.
Wolfgang Woiwode, Andreas Dörnbrack, Martina Bramberger, Felix Friedl-Vallon, Florian Haenel, Michael Höpfner, Sören Johansson, Erik Kretschmer, Isabell Krisch, Thomas Latzko, Hermann Oelhaf, Johannes Orphal, Peter Preusse, Björn-Martin Sinnhuber, and Jörn Ungermann
Atmos. Chem. Phys., 18, 15643–15667, https://doi.org/10.5194/acp-18-15643-2018, https://doi.org/10.5194/acp-18-15643-2018, 2018
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GLORIA observations during two crossings of the polar front jet stream resolve the fine mesoscale structure of a tropopause fold in high detail. Tracer–tracer correlations of H2O and O3 are presented as a function of potential temperature and reveal an active mixing region. Our study confirms conceptual models of tropopause folds, validates the high quality of ECMWF IFS forecasts, and suggests that mountain waves are capable of modulating exchange processes in the vicinity of tropopause folds.
Andrea K. Steiner, Bettina C. Lackner, and Mark A. Ringer
Atmos. Chem. Phys., 18, 4657–4672, https://doi.org/10.5194/acp-18-4657-2018, https://doi.org/10.5194/acp-18-4657-2018, 2018
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We evaluate the representation of tropical convection regimes in atmospheric climate models with satellite-based observations from GPS radio occultation. We find that models have large temperature biases in the tropopause region. In moist convection regions, models underestimate moisture up to 40 % over oceans whereas in dry regions they overestimate it by 100 %. Our findings show that RO observations are a valuable data source for the evaluation and development of next generation climate models.
Robin Pilch Kedzierski, Katja Matthes, and Karl Bumke
Atmos. Chem. Phys., 17, 4093–4114, https://doi.org/10.5194/acp-17-4093-2017, https://doi.org/10.5194/acp-17-4093-2017, 2017
Wanchun Zhang, Jianping Guo, Yucong Miao, Huan Liu, Yong Zhang, Zhengqiang Li, and Panmao Zhai
Atmos. Chem. Phys., 16, 9951–9963, https://doi.org/10.5194/acp-16-9951-2016, https://doi.org/10.5194/acp-16-9951-2016, 2016
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The PBL height retrieval from CALIOP aboard CALIPSO can significantly complement the traditional ground-based methods, which is only for one site. Our study, to our current knowledge, is the first intercomparison study of PBLH on a large scale using long-term radiosonde observations in China. Three matchup schemes were proposed based on the position of radiosondes relative to CALIPSO ground tracks in China. Results indicate that CALIOP is promising for reliable PBLH retrievals.
Lukas Brunner, Andrea K. Steiner, Barbara Scherllin-Pirscher, and Martin W. Jury
Atmos. Chem. Phys., 16, 4593–4604, https://doi.org/10.5194/acp-16-4593-2016, https://doi.org/10.5194/acp-16-4593-2016, 2016
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Atmospheric blocking refers to persistent high-pressure systems which block the climatological flow at midlatitudes. We explore blocking with observations from GPS radio occultation (RO), a satellite-based remote-sensing system. Using two example cases, we find that RO data robustly capture blocking, highlighting the potential of RO observations to complement models and reanalysis as a basis for blocking research.
Christopher E. Sioris, Jason Zou, David A. Plummer, Chris D. Boone, C. Thomas McElroy, Patrick E. Sheese, Omid Moeini, and Peter F. Bernath
Atmos. Chem. Phys., 16, 3265–3278, https://doi.org/10.5194/acp-16-3265-2016, https://doi.org/10.5194/acp-16-3265-2016, 2016
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The AM (annular mode) is the most important internal mode of climatic variability at high latitudes. Upper tropospheric water vapour (UTWV) at high latitudes increases by up to ~ 50 % during the negative phase of the AMs. The response of water vapour to the AMs vanishes above the tropopause. The ultimate goal of the study was to improve UTWV trend uncertainties by explaining shorter-term variability, and this was achieved by accounting for the AM-related response in a multiple linear regression.
Guiqian Tang, Jinqiang Zhang, Xiaowan Zhu, Tao Song, Christoph Münkel, Bo Hu, Klaus Schäfer, Zirui Liu, Junke Zhang, Lili Wang, Jinyuan Xin, Peter Suppan, and Yuesi Wang
Atmos. Chem. Phys., 16, 2459–2475, https://doi.org/10.5194/acp-16-2459-2016, https://doi.org/10.5194/acp-16-2459-2016, 2016
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This is the first paper to validate and characterize mixing layer height and discuss its relationship with air pollution, using a ceilometer in Beijing. The novelty, originality, and importance of this paper are as follows: (1) the applicable conditions of the ceilometer; (2) the variations of mixing layer height; (3) thermal/dynamic structure inside mixing layers with different degrees of pollution; and (4) critical meteorological conditions for the formation of heavy air pollution.
S. Ravindra Babu, M. Venkat Ratnam, G. Basha, B. V. Krishnamurthy, and B. Venkateswararao
Atmos. Chem. Phys., 15, 10239–10249, https://doi.org/10.5194/acp-15-10239-2015, https://doi.org/10.5194/acp-15-10239-2015, 2015
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The effect of tropical cyclones (TCs) that occurred over the north Indian Ocean in the last decade on the tropical tropopause parameters has been quantified for the first time. The vertical structure of temperature and tropopause parameters within the 5º radius away from the cyclone centre during TC period is also presented. The water vapour variability in the vicinity of TC is investigated.
It is demonstrated that the TCs can significantly affect the tropical tropopause and thus STE processes.
N. Andela, J. W. Kaiser, G. R. van der Werf, and M. J. Wooster
Atmos. Chem. Phys., 15, 8831–8846, https://doi.org/10.5194/acp-15-8831-2015, https://doi.org/10.5194/acp-15-8831-2015, 2015
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The polar orbiting MODIS instruments provide four daily observations of the fire diurnal cycle, resulting in erroneous fire radiative energy (FRE) estimates. Using geostationary SEVIRI data, we explore the fire diurnal cycle and its drivers for Africa to develop a new method to estimate global FRE in near real-time using MODIS. The fire diurnal cycle varied with climate and vegetation type, and including information on the fire diurnal cycle in the model significantly improved the FRE estimates.
J. R. Ziemke, A. R. Douglass, L. D. Oman, S. E. Strahan, and B. N. Duncan
Atmos. Chem. Phys., 15, 8037–8049, https://doi.org/10.5194/acp-15-8037-2015, https://doi.org/10.5194/acp-15-8037-2015, 2015
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Aura OMI and MLS measurements are combined to produce daily maps of tropospheric ozone beginning October 2004. We show that El Niño Southern Oscillation (ENSO) related inter-annual change in tropospheric ozone in the tropics is small compared to combined intra-seasonal/Madden-Julian Oscillation (MJO) and shorter timescale variability. Outgoing Longwave Radiation indicates that deep convection is the primary driver of the observed ozone variability on all timescales.
A. Sandeep, T. N. Rao, and S. V. B. Rao
Atmos. Chem. Phys., 15, 7605–7617, https://doi.org/10.5194/acp-15-7605-2015, https://doi.org/10.5194/acp-15-7605-2015, 2015
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The afternoon-evening transition (AET) in the atmospheric boundary layer has been studied in an integrated approach using 3 years of tower, sodar and wind profiler measurements. Such a long-term data set has been used for the first time to understand the behavior of AET. It allowed us to study the seasonal variation. In contrast to the common belief that the transition evolves from bottom to top, the present study clearly showed that the start time of transition follows top-to-bottom evolution.
R. Biondi, A. K. Steiner, G. Kirchengast, and T. Rieckh
Atmos. Chem. Phys., 15, 5181–5193, https://doi.org/10.5194/acp-15-5181-2015, https://doi.org/10.5194/acp-15-5181-2015, 2015
H. Vogelmann, R. Sussmann, T. Trickl, and A. Reichert
Atmos. Chem. Phys., 15, 3135–3148, https://doi.org/10.5194/acp-15-3135-2015, https://doi.org/10.5194/acp-15-3135-2015, 2015
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We quantitatively analyzed the spatiotemporal variability (minutes to hours, 500m to 10km) of water vapor (IWV and profiles) in the free troposphere recorded at the Zugspitze (Germany) with lidar and solar FTIR. We found that long-range transport of heterogeneous air masses may cause relative short-term variations of the water-vapor density which exceed the impact of local convection by 1 order of magnitude. Our results could be useful for issues of model parametrization and co-location.
E. Hammann, A. Behrendt, F. Le Mounier, and V. Wulfmeyer
Atmos. Chem. Phys., 15, 2867–2881, https://doi.org/10.5194/acp-15-2867-2015, https://doi.org/10.5194/acp-15-2867-2015, 2015
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Measurements and upgrades of the rotational Raman lidar of the University of Hohenheim during the HD(CP)2 Observational Prototype Experiment are presented in this paper. This includes 25h long time series of temperature gradients and water vapor mixing ratio. Through simulation, optimum wavelengths for high- and low-background cases were identified and tested successfully. Low-elevation measurements were performed to measure temperature gradients at altitudes around 100m above ground level.
M. Collaud Coen, C. Praz, A. Haefele, D. Ruffieux, P. Kaufmann, and B. Calpini
Atmos. Chem. Phys., 14, 13205–13221, https://doi.org/10.5194/acp-14-13205-2014, https://doi.org/10.5194/acp-14-13205-2014, 2014
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An operational planetary boundary layer height detection method with several remote sensing instruments (wind profiler, Raman lidar, microwave radiometer) and algorithms (Parcel and bulk Richardson number methods, surface-based temperature inversion, aerosol and humidity gradient analysis) was validated against radio sounding. A comparison with the numerical weather prediction model COSMO-2 and the seasonal cycles of the day- and nighttime PBL for two stations on the Swiss plateau are presented.
Yuanchun Zhang, Fuqing Zhang, and Jianhua Sun
Atmos. Chem. Phys., 14, 10741–10759, https://doi.org/10.5194/acp-14-10741-2014, https://doi.org/10.5194/acp-14-10741-2014, 2014
T. Trickl, H. Vogelmann, H. Giehl, H.-E. Scheel, M. Sprenger, and A. Stohl
Atmos. Chem. Phys., 14, 9941–9961, https://doi.org/10.5194/acp-14-9941-2014, https://doi.org/10.5194/acp-14-9941-2014, 2014
F. Carminati, P. Ricaud, J.-P. Pommereau, E. Rivière, S. Khaykin, J.-L. Attié, and J. Warner
Atmos. Chem. Phys., 14, 6195–6211, https://doi.org/10.5194/acp-14-6195-2014, https://doi.org/10.5194/acp-14-6195-2014, 2014
A. Devasthale, J. Sedlar, T. Koenigk, and E. J. Fetzer
Atmos. Chem. Phys., 13, 7441–7450, https://doi.org/10.5194/acp-13-7441-2013, https://doi.org/10.5194/acp-13-7441-2013, 2013
R. D. Hudson
Atmos. Chem. Phys., 12, 7797–7808, https://doi.org/10.5194/acp-12-7797-2012, https://doi.org/10.5194/acp-12-7797-2012, 2012
I. M. Lensky and U. Dayan
Atmos. Chem. Phys., 12, 6505–6513, https://doi.org/10.5194/acp-12-6505-2012, https://doi.org/10.5194/acp-12-6505-2012, 2012
R. Biondi, W. J. Randel, S.-P. Ho, T. Neubert, and S. Syndergaard
Atmos. Chem. Phys., 12, 5309–5318, https://doi.org/10.5194/acp-12-5309-2012, https://doi.org/10.5194/acp-12-5309-2012, 2012
F. Xie, D. L. Wu, C. O. Ao, A. J. Mannucci, and E. R. Kursinski
Atmos. Chem. Phys., 12, 903–918, https://doi.org/10.5194/acp-12-903-2012, https://doi.org/10.5194/acp-12-903-2012, 2012
S.-Y. Lee and T. Y. Koh
Atmos. Chem. Phys., 12, 669–681, https://doi.org/10.5194/acp-12-669-2012, https://doi.org/10.5194/acp-12-669-2012, 2012
G. Beyerle, L. Grunwaldt, S. Heise, W. Köhler, R. König, G. Michalak, M. Rothacher, T. Schmidt, J. Wickert, B. D. Tapley, and B. Giesinger
Atmos. Chem. Phys., 11, 6687–6699, https://doi.org/10.5194/acp-11-6687-2011, https://doi.org/10.5194/acp-11-6687-2011, 2011
A. Ansmann, J. Fruntke, and R. Engelmann
Atmos. Chem. Phys., 10, 7845–7858, https://doi.org/10.5194/acp-10-7845-2010, https://doi.org/10.5194/acp-10-7845-2010, 2010
G. Pearson, F. Davies, and C. Collier
Atmos. Chem. Phys., 10, 5891–5901, https://doi.org/10.5194/acp-10-5891-2010, https://doi.org/10.5194/acp-10-5891-2010, 2010
J. R. Ziemke, S. Chandra, L. D. Oman, and P. K. Bhartia
Atmos. Chem. Phys., 10, 3711–3721, https://doi.org/10.5194/acp-10-3711-2010, https://doi.org/10.5194/acp-10-3711-2010, 2010
S. Kirkwood, M. Mihalikova, T. N. Rao, and K. Satheesan
Atmos. Chem. Phys., 10, 3583–3599, https://doi.org/10.5194/acp-10-3583-2010, https://doi.org/10.5194/acp-10-3583-2010, 2010
Cited articles
Arnault, J. and Kirkwood, S.: Dynamical influence of gravity waves generated by the {V}estfjella {M}ountains in {A}ntarctica: radar observations, fine-scale modelling and kinetic energy budget analysis, Tellus A, 64, 17261, https://doi.org/10.3402/tellusa.v64i0.17261, 2012.
Bertin, F., Campistron, B., Caccia, J. L., and Wilson, R.: Mixing processes in a tropopause fold observed by a network of ST radar and lidar, Ann.\ Geophysicae, 19, 953–963, 2001.
Bethan, S., Vaughan, G., and Reid, S. J.: A comparison of ozone and thermal tropopause heights and the impact of tropopause definition on quantifying the ozone content of the troposphere, Q. J. R. Meteorol. Soc., 122, 929–944, 1996.
Birner, T.: Fine-scale structure of the extratropical tropopause region, J.\ Geophys. Res., 111, D04104, https://doi.org/10.1029/2005JD006301, 2006.
Birner, T., Dörnbrack, A., and Schumann, U.: How sharp is the tropopause at midlatitudes?, Geophys. Res. Lett., 29, 1700, https://doi.org/10.1029/2002GL015142, 2002.
Caccia, J. L., Bertin, F., Campistron, B., Klaus, V., Pointin, Y., van Baelen, J., and Wilson, R.: Cut-off low monitoring by the F}rench {VHF-ST radar network during the ESTIME campaign, J. Atmos. Sol. Terr. Phys., 62, 639–651, 2000.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P. , Bechtold, P., Beljaars, A. C. M., van de Berg, L., Bidlot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S. B. Hersbach, H. , Holm, E. V., Isaksen, L. , Kallberg, P., Kohler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K., Peubey, C., de Rosnay, P., Tavolato, C. Thepaut, J.-N., and Vitart, F.: The {ERA-I}nterim reanalysis: configuration and performance of the data assimilation system, Q. J. R. Meteorol. Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011.
Doviak, R. J. and Zrnic, D. S.: Doppler radar and weather observations, Academic Press, 1984.
Gage, K. S. and Green, J. L.: Tropopause detection by partial specular reflection with very high frequency radar, Science, 203, 1238–1240, 1979.
Gage, K. S. and Green, J. L.: An objective method for the determination of tropopause height from VHF radar observations, J. Appl. Meteor., 21, 1150–1154, 1982.
Gettelman, A., Hoor, P., Pan, L. L., Randel, W. J., Hegglin, M. I., and Birner, T.: The extratropical upper troposphere and lower stratosphere, Rev.\ Geophys., 49, RG3003, https://doi.org/10.1029/2011RG000355, 2011.
Hall, C. M., Röttger, J., Kuyeng, K., Sigernes, F., Claes, S., and Chau, J.: First results of the refurbished SOUSY radar: {T}ropopause altitude climatology at $78^\circ$ N, $16^\circ$ E, 2008, Radio Sci., 44, RS5008, https://doi.org/10.1029/2009RS004144, 2009.
Hall, C. M., Hansen, G., Sigernes, F., and Kuyeng Ruiz, K. M.: Tropopause height at $78^\circ${N} $16^\circ${E}: average seasonal variation 2007–2010, Atmos. Chem. Phys., 11, 5485–5490, https://doi.org/10.5194/acp-11-5485-2011, 2011.
Hegglin, M. I., Boone, C. D., Manney, G. L., and Walker, K. A.: A global view of the extratropical tropopause transition layer from A}tmospheric {C}hemistry {E}xperiment {F}ourier {T}ransform {S}pectrometer O3, H2O and {CO, J. Geophys. Res., 114, D00B11, https://doi.org/10.1029/2008JD009984, 2009.
Hocking, W. K., Carey-Smith, T., Tarasick, D. W., Argall, P. S., Strong, K., Rochon, Y., Zawadzki, I., and Taylor, P. A.: Detection of stratospheric ozone intrusions by windprofiler radars, Nature, 450, 281–284, https://doi.org/10.1038/nature06312, 2007.
Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R., Rood, R. B., and Pfister, L.: Stratosphere – {T}roposphere {E}xchange, Rev. Geophys., 33, 403–439, 1995.
Hooper, D. A. and Arvelius, J.: Monitoring of the A}rctic winter tropopause: {A comparison of radiosonde, ozonesonde and MST radar observations, in: 9th international workshop on technical and scientific aspects of MST radar, Sci. Comm. on Sol. Terr. Phys., Toulouse, France, 2000.
Hoskins, B. J., McIntyre, M. E., and Robertson, A. W.: On the use and significance of isentropic potential vorticity maps, Q. J. R. Meteorol.\ Soc., 111, 877–946, 1985.
Lucas, C., May, P. T., and Vincent, R. A.: An algorithm for the detection of fronts in wind profiler data, Weather Forecast., 16, 234–247, 2001.
May, P. T., Yamamoto, M., Fukao, S., Sato, T., Kato, S., and Tsuda, T.: Wind and reflectivity fields around fronts observed with a VHF radar, Radio Sci., 26, 1245–1249, 1991.
Mihalikova, M., Kirkwood, S., Arnault, J., and Mikhaylova, D.: Observation of a tropopause fold by MARA VHF wind-profiler radar and ozonesonde at Wasa, Antarctica: comparison with ECMWF analysis and a WRF model simulation, Ann. Geophys., 30, 1411–1421, https://doi.org/10.5194/angeo-30-1411-2012, 2012.
Morris, R. J., Murphy, D. J., Vincent, R. A., Holdsworth, D. A., Klekociuk, A. R., and Reid, I. M.: Characteristics of the wind, temperature and PMSE field above {D}avis, {A}ntarctica, J. Atmos. Sol. Terr. Phys., 68, 418–435, 2006.
Nastrom, G. D., Green, J. L., Peterson, M. R., and Gage, K. S.: Tropopause folding and the variability of the tropopause height as seen by the F}latland {VHF radar, J. Appl. Meteor., 28, 1271–1281, 1989.
Ottersten, H.: Atmospheric structure and radar backscattering in clear air, Radio Sci., 4, 1247–1249, 1969.
Pan, L. L. and Munchak, L. A.: Relationship of cloud top to the tropopause and jet structure from CALIPSO data, J. Geophys. Res., 116, D12201, https://doi.org/10.1029/2010JD015462, 2011.
Pan, L. L., Randel, W. J., Gary, B. L., Mahoney, M. J., and Hintsa, E. J.: Definitions and sharpness of the extratropical tropopause: A trace gas perspective, J. Geophys. Res., 109, D23103, https://doi.org/10.1029/2004JD004982, 2004.
Pan, L. L., Randel, W. J., Gille, J. C., Hall, W. D., Nardi, B., Massie, S., Yudin, V., Khosravi, R., Konopka, P., and Tarasick, D.: Tropospheric intrusions associated with the secondary tropopause, J. Geophys. Res., 114, D10302, https://doi.org/10.1029/2008JD011374, 2009.
Randel, W. J. and Wu, F.: The polar summer tropopause inversion layer, J.\ Atmos. Sci., 67, 2572–2581, https://doi.org/10.1175/2010JAS3430.1, 2010.
Randel, W. J., Wu, F., and Forster, P.: The extratropical tropopause inversion layer: G}lobal observations with {GPS data, and a radiative forcing mechanism, J. Atmos. Sci., 64, 4489–4496, 2007.
Rao, T. N., Arvelius, J., and Kirkwood, S.: Climatology of tropopause folds over a {E}uropean {A}rctic station ({E}srange), J. Geophys. Res., 113, D00B03, https://doi.org/10.1029/2007JD009638, 2008.
Reid, H. J. and Vaughan, G.: Convective mixing in a tropopause fold, Q. J.\ R. Meteorol. Soc., 130, 1195–1212, https://doi.org/10.1256/qj.03.21, 2004.
Sprenger, M., Maspoli, M. C., and Wernli, H.: Tropopause folds and cross-tropopause exchange: A global investigation based upon ECMWF analyses for the time period {M}arch 2000 to {F}ebruary 2001, J. Geophys.\ Res., 108, 8518, https://doi.org/10.1029/2002JD002587, 2003.
Sprenger, M., Wernli, H., and Bourqui, M.: Stratosphere – troposphere exchange and its relation to potential vorticity streamers and cutoffs near the extratropical tropopause, J. Atmos. Sci., 64, 1587–1603, https://doi.org/10.1175/JAS3911.1, 2007.
Stohl, A., Bonasoni,P., Cristofanelli, P., Collins, W., Feichter, J., Frank, A., Forster, C., Gerasopoulos, E., Gaggeler,H., James, P., Kentarchos, T., Kromp-Kolb, H., Kruger, B., Land, C., Meloen, J., Papayannis, A., Priller, A., Seibert, P., Sprenger, M., Roelofs, G. J., Scheel, H. E., Schnabel, C., Siegmund, P., Tobler, L., Trickl, T., Wernli, H., Wirth, V., Zanis, P., and Zerefos, C.: Stratosphere-troposphere exchange: A review, and what we have learned from STACCATO, J. Geophys. Res., 8516, https://doi.org/10.1029/2002JD002490, 2003.
Tomikawa, Y., Nishimura, Y., and Yamanouchi, T.: Characteristics of tropopause and tropopause inversion layer in the polar region, Sci. Online Lett.\ Atmos., 5, 141–144, https://doi.org/10.2151/sola.2009-036, 2009.
Tsuda, T., May, P. T., Sato, T., Kato, S., and Fukao, S.: Simultaneous observations of reflection echoes and refractive index gradient in the troposphere and lower stratosphere, Radio Sci., 23, 655–665, 1988.
Valkonen, T., Vihma, T., Kirkwood, S., and Johansson, M.: Fine-scale modelling simulation of gravity waves generated by {B}asen nunatak in {A}ntarctica, Tellus, 62A, 319–332, 2010.
Vaughan, G. and Timmis, C.: Transport of near-tropopause air into the lower midlatitude stratosphere, Q. J. R. Meteorol. Soc., 124, 1559–1578, 1998.
Vaughan, G. and Worthington, R. M.: Break-up of a stratospheric streamer observed by MST radar, Q. J. R. Meteorol. Soc., 126, 1751–1769, 2000.
Vaughan, G., Howells, A., and Price, J. D.: Use of MST radars to probe the mesoscale structure of the tropopause, Tellus, 47A, 759–765, 1995.
Wernli, H. and Sprenger, M.: Identification and {ERA}-15 climatology of potential vorticity streamers and cutoffs near the extratropical tropopause, J. Atmos. Sci., 64, 1569–1586, https://doi.org/10.1175/JAS3912.1, 2007.
Wilcox, L. J., Hoskins, B. J., and Shine, K. P.: A global blended tropopause based on ERA data. {P}art {I}: {C}limatology, Q. J. R. Meteorol. Soc., 138, 561–575, 2011.
Wirth, V.: Thermal versus dynamical tropopause in upper-tropospheric balanced flow anomalies, Q. J. R. Meteorol. Soc., 299–317, 2000.
Wirth, V.: Cyclone – {A}nticyclone asymmetry concerning the height of the thermal and the dynamical tropopause, J. Atmos. Sci., 58, 26–37, 2001.
Wirth, V.: Static stability in the extratropical region, J. Atmos. Sci., 60, 1395–1409, 2003.
World Meteorological Organization: Meteorology – a three-dimensional science: {S}econd session of the {C}ommission for {A}erology, 1957.
Zängl, G. and Hoinka, K. P.: The tropopause in the polar regions, J.\ Climate, 14, 3117–3139, 2001.
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