Atmospheric Temperature Changes and their Drivers (ATC)

Activity leaders

Andrea Steiner
Wegener Center for Climate and Global Change, Graz, Austria

Stephen Po-Chedley
Lawrence Livermore National Laboratory, CA, USA

Amanda Maycock (2016 – 2021)
University of Leeds, Leeds, UK

Team members

In memory of our deeply missed colleague Chantal Claud, LMD, Ecole Polytechnique, CNRS, Palaiseau, France!

  • Jiawei Biao, Institute of Science and Technology (IST), Austria
  • Lukas Brunner, Climate Extremes Group, University of Hamburg, Germany
  • Martin Dameris, Institute of Atmospheric Physics, DLR, Oberpfaffenhofen, Germany (APARC CCMI contact)
  • Qiang Fu, Department of Atmospheric Sciences, University of Washington, Seattle, USA
  • Nathan Gillett, Canadian Center for Climate Modeling and Analysis, Victoria, BC, Canada
  • Hans Gleisner, Danish Meteorological Institute, Copenhagen, Denmark
  • Leopold Haimberger, Institute for Meteorology and Geophysics, University of Vienna, Austria
  • Ben Ho, NOAA NESDIS/STAR/SMCD Center for Weather and Climate Prediction, Washington D.C., USA
  • Philippe Keckhut, LATMOS, Université Pierre-et-Marie-Curie, Paris, France
  • Florian Ladstädter, Wegener Center for Climate and Global Change, Graz, Austria
  • Alexandra Laeng, Karlsruhe Institute of Technology, DE
  • Thierry Leblanc, JPL, Pasadena, USA (GCOS GRUAN contact)
  • Carl Mears, Remote Sensing Systems, Santa Rosa, USA
  • Osamu Miyawaki, Union College, Schenectady, NY, USA
  • Stephen Po-Chedley, PCMDI, Lawrence Livermore National Laboratory, Livermore, USA
  • Lorenzo M. Polvani, Columbia University, New York, NY, USA
  • William (Bill) Randel,  NCAR, Boulder, USA
  • Ben Santer, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
  • Torsten Schmidt, Helmholtz Centre, German Research Centre for Geosciences, Potsdam, Germany
  • Michael Schwartz, JPL, Pasadena, USA
  • Martin Singh, Monash University, Clayton, Victoria, Australia
  • Viktoria Sofieva, Finnish Meteorological Institute, Helsinki, Finland
  • Matthias Stocker, Wegener Center University of Graz, Austria
  • Aodhan Sweeney, University of Washington, Seattle, USA
  • Dave Thompson, Colorado State University, Fort Collins, USA
  • Jun Zhou, CISESS, University of Maryland, College Park, MD, USA
  • Cheng-Zhi Zou, George Mason University, Fairfax, VA, USA

Upcoming Events

APARC ATC Spring Meeting, April 23–25, 2025 in Graz, Austria at the Wegener Center for Climate and Global Change, University of Graz

The goal of our APARC ATC Spring meeting is to present our latest research results, to identify key science problems that we can collectively address, and to organize and contribute to community organized papers.
Please fill out this form for attendance.

Activity description

The focus of the Atmospheric Temperature Changes and their Drivers (ATC) activity is on characterising observed temperature changes and their uncertainties from different measurements, and on disentangling the drivers of past and future temperature changes in observations and global models. The ATC activity has evolved and broadened out from the work of the long-standing SPARC Stratospheric Temperature Trends activity. The science objectives of the new ATC activity align with the themes in SPARC’s new Implementation Plan on ‘Long-term Records for Climate Understanding’, ‘Chemistry and Climate’, and ‘Atmospheric Dynamics and Predictability’. Output from the group provides key information for UNEP/WMO Ozone Assessments and the Intergovernmental Panel on Climate Change (IPCC) Reports, as well as for other SPARC activities including CCMI and S-RIP.

Atmospheric temperature variability and trends, and their uncertainty in climate records

The IPCC AR5 states as a key uncertainty: “There is only medium to low confidence in the rate of change of tropospheric warming and its vertical structure…. There is low confidence in the rate and vertical structure of the stratospheric cooling”. The aim of the ATC activity is to gain a better insight into atmospheric climate variability and trends from the troposphere to the mesosphere. This includes the evaluation of the inter-consistency of atmospheric temperature observations, comparison with (chemistry) climate models and reanalyses, and the provision of uncertainty information. Specific foci include: (1) extension of region of interest to the troposphere and the mesosphere; (2) inclusion of emerging novel observational records (such as radio occultation and Global Climate Observing System (GCOS) Reference Upper-Air Network (GRUAN) radiosondes); and (3) improving uncertainty information towards enhancing the maturity and benchmarking of climate records.

Radiative and dynamical contributions to observed and modelled temperature changes

Understanding the causes of temperature variations and trends requires knowledge of dynamical and radiative processes. Considerable effort has been placed in comparing model simulations of atmospheric temperatures to observations, but these studies have not attempted to assess the consistency between changes in temperature, composition (e.g. water vapour and ozone) and dynamics. The ATC activity is focused on assessing these contributions and their effect on observed and simulated atmospheric temperature trends. Specific foci include: (1) the contribution of greenhouse gases, ozone, and water vapour to temperature trends; (2) the role of natural variations (solar cycle, volcanoes, dynamical variability) in determining temperature variability; and (3) determining the drivers of temperature variability and trends on seasonal and regional scales.

Published results

Contributions to the IPCC AR 6:

Gulev et al. (2021). Changing state of the climate system. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. [Masson-Delmotte, V., et al. (eds)], Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 287–422, https://doi.org/10.1017/9781009157896.004

Arias, P.A., et al. (2021): Technical Summary. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Masson-Delmotte, V., et al. (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 33−144. https://doi.org/10.1017/9781009157896.002

Recent ATC community paper:

Steiner, A. K., F. Ladstädter, W. J. Randel, A. C. Maycock, Q. Fu, C. Claud, H. Gleisner, L. Haimberger, S.-P. Ho, P. Keckhut, T. Leblanc, C. Mears, L. Polvani, B. Santer, T. Schmidt, V. Sofieva, R. Wing, and C.-Z. Zou (2020), Observed temperature changes in the troposphere and stratosphere from 1979 to 2018, J. Climate, 33(19), 8165–8194. https://doi.org/10.1175/JCLI-D-19-0998.1

Journal publications:
2024

Po-Chedley, S., J. R. Christy, L. Haimberger, C. A. Mears, and C.-Z. Zou (2024), Tropospheric temperature, In: State of the Climate in 2023, Section 2 Global Climate, Bull. Amer. Meteor. Soc., 105(8),  https://doi.org/10.1175/BAMS-D-24-0116.1

Randel, W. J., C. Covey, L. Polvani, and A. K. Steiner (2024), Stratospheric temperature, In: State of the Climate in 2023, Section 2 Global Climate, Bull. Amer. Meteor. Soc., 105(8), https://doi.org/10.1175/BAMS-D-24-0116.1

Shi, J-C., B. D. Santer, Y-O. Kwon, and S. E. Wijffels (2024), The emerging human influence on the seasonal cycle of surface temperature, Nature Climate Change, https://doi.org/10.1038/s41558-024-01958-8

Stocker, M., A. K. Steiner, F. Ladstädter, U. Foelsche, and W. J. Randel (2024), Observed impacts of the Hunga Tonga eruption on stratospheric temperature, Commun. Earth Environ., (in revision).

Sweeney, A., and Q. Fu, (2024), Interannual variability of zonal mean temperature, water vapor, and clouds in the tropical tropopause layer, J. Geophys. Res. 129(3), e2023JD039002, https://doi.org/10.1029/2023JD039002

Sweeney, A. J., Q. Fu, S. Po-Chedley, H. Wang, and M. Wang (2024), Unique global temperature trend pattern associated with internally driven arctic warming and global cooling during 1980-2022, Geophys. Res. Lett., 51, e2024GL108798, https://doi.org/10.1029/2024GL108798

Zhou, J., S.-P. Ho, X. Zhou, et al. (2024), Construction of temperature climate data records in the upper troposphere and lower stratosphere using multiple RO missions from 2006 to 2023 at NESDIS/STAR, April 12, 2024, ESS Open Archive (in review), https://doi.org/10.22541/essoar.171288985.57901527/v1

2023

Ladstädter, F., Steiner, A. K., & Gleisner, H. (2023). Resolving the 21st century temperature trends of the upper troposphere–lower stratosphere with satellite observations. Scientific Reports, 13(1), 1306. https://doi.org/10.1038/s41598-023-28222-x

Santer, B. D., Po-Chedley, S., Zhao, L., Zou, C.-Z., Fu, Q., Solomon, S., et al. (2023). Exceptional stratospheric contribution to human fingerprints on atmospheric temperature. Proc. National Academy of Sciences, 120(20), e2300758120. https://doi.org/10.1073/pnas.2300758120

Sigmond, M., Polvani, L. M., Fyfe, J. C., Smith, C. J., Cole, J. N. S., & England, M. R. (2023). Large Contribution of Ozone‐Depleting Substances to Global and Arctic Warming in the Late 20th Century. Geophys. Res. Letters, 50(5), e2022GL100563. https://doi.org/10.1029/2022GL100563

Von Schuckmann, K., Minière, A., Gues, F., Cuesta-Valero, F. J., Kirchengast, G., Adusumilli, S., et al. (2023). Heat stored in the Earth system 1960–2020: where does the energy go? Earth Syst. Sci. Data, 15(4), 1675–1709. https://doi.org/10.5194/essd-15-1675-2023

Zou, C.-Z., Xu, H., Hao, X., & Liu, Q. (2023). Mid-Tropospheric Layer Temperature Record Derived From Satellite Microwave Sounder Observations With Backward Merging Approach. J Geophys Res, 128(6), e2022JD037472. https://doi.org/10.1029/2022JD037472

2022

Dunn, R. J. H., F. Aldred, N. Gobron, J. B Miller, and K. M. Willett, Eds. (2022), Global Climate, In: State of the Climate in 2021, Bull. Amer. Meteor. Soc., 103 (8), S11–S142, https://doi.org/10.1175/BAMS-D-22-0092.1

Haimberger, L., M. Mayer, and V. Schenzinger (2022), Upper-air winds, In: State of the Climate in 2021, Section 2 Global Climate, Dunn et al. (Eds.), Bull. Amer. Meteor. Soc., 103(8), S11–S142, https://doi.org/10.1175/BAMS-D-22-0092.1

Mariaccia, A., Keckhut, P., Hauchecorne, A., Claud, C., Le Pichon, A., Meftah, M., & Khaykin, S. (2022). Assessment of ERA-5 Temperature Variability in the Middle Atmosphere Using Rayleigh LiDAR Measurements between 2005 and 2020. Atmosphere, 13(2), 242. https://doi.org/10.3390/atmos13020242

Mears, C. A., J. P. Nicolas, O. Bock, S. P. Ho, and X. Zhou (2022), Total column water vapor, In: State of the Climate in 2021, Section 2 Global Climate, Dunn et al. (Eds.), Bull. Amer. Meteor. Soc., 103(8), S11–S142, https://doi.org/10.1175/BAMS-D-22-0092.1

Randel, W. J., C. Covey, L. Polvani, and A. K. Steiner (2022), Stratospheric temperature, In: State of the Climate in 2021, Section 2 Global Climate, Dunn et al. (Eds.), Bull. Amer. Meteor. Soc., 103(8), S11–S142, https://doi.org/10.1175/BAMS-D-22-0092.1

Po-Chedley, S., J. R. Christy, L. Haimberger, and C. A. Mears (2022), Tropospheric temperature, , In: State of the Climate in 2021, Section 2 Global Climate, Dunn et al. (Eds.), Bull. Amer. Meteor. Soc., 103(8), S11–S142, https://doi.org/10.1175/BAMS-D-22-0092.1

Santer, B. D., Po-Chedley, S., Feldl, N., Fyfe, J. C., Fu, Q., Solomon, S., et al. (2022). Robust Anthropogenic Signal Identified in the Seasonal Cycle of Tropospheric Temperature. J. Climate, 35(18), 6075–6100. https://doi.org/10.1175/JCLI-D-21-0766.1

2021

Banerjee, A., Fyfe, J.C., Polvani, L.M. et al. A pause in Southern Hemisphere circulation trends due to the Montreal Protocol. Nature 579, 544–548 (2020). https://doi.org/10.1038/s41586-020-2120-4

Marlton, G., Charlton-Perez, A., Harrison, G., Polichtchouk, I., Hauchecorne, A., Keckhut, P., Wing, R., Leblanc, T., and Steinbrecht, W. (2021). Using a network of temperature lidars to identify temperature biases in the upper stratosphere in ECMWF reanalyses. Atmospheric Chemistry and Physics, 21(8), 6079–6092. https://doi.org/10.5194/acp-21-6079-2021

Meng, L., Liu, J., Tarasick, D. W., Randel, W. J., Steiner, A. K., Wilhelmsen, H., et al. (2021). Continuous rise of the tropopause in the Northern Hemisphere over 1980–2020. Science Advances, 7(45), eabi8065. https://doi.org/10.1126/sciadv.abi8065

Pisoft, P., Sacha, P., Polvani, L. M., Añel, J. A., Torre, L. de la, Eichinger, R., Foelsche, U., Huszar, P., Jacobi, C., Karlicky, J., Kuchar, A., Miksovsky, J., Zak, M., and Rieder, H. E. (2021). Stratospheric contraction caused by increasing greenhouse gases. Environmental Research Letters, 16(6), 064038. https://doi.org/10.1088/1748-9326/abfe2b

Po-Chedley, S., Santer, B. D., Fueglistaler, S., Zelinka, M. D., Cameron-Smith, P. J., Painter, J. F., & Fu, Q. (2021). Natural variability contributes to model–satellite differences in tropical tropospheric warming. Proc. National Academy of Sciences, 118(13). https://doi.org/10.1073/pnas.2020962118

Randel, W. J., Wu, F., & Podglajen, A. (2021). Equatorial Waves, Diurnal Tides and Small-Scale Thermal Variability in the Tropical Lower Stratosphere From COSMIC-2 Radio Occultation. J. Geophys. Res., 126(7), https://doi.org/10.1029/2020JD033969

Rieger, L. A., Randel, W. J., Bourassa, A. E., & Solomon, S. (2021). Stratospheric Temperature and Ozone Anomalies Associated With the 2020 Australian New Year Fires. Geophysical Research Letters, 48(24), e2021GL095898. https://doi.org/10.1029/2021GL095898

Santer, B. D., Po-Chedley, S., Mears, C., Fyfe, J. C., Gillett, N., Fu, Q., et al. (2021). Using Climate Model Simulations to Constrain Observations. J. Climate, 34(15), 6281–6301. https://doi.org/10.1175/JCLI-D-20-0768.1

Scherllin-Pirscher, B., Steiner, A. K., Anthes, R. A., Alexander, M. J., Alexander, S. P., Biondi, R., et al. (2021). Tropical Temperature Variability in the UTLS: New Insights from GPS Radio Occultation Observations. J. Climate, 34(8), 2813–2838. https://doi.org/10.1175/JCLI-D-20-0385.1

Shao, X., Ho, S., Zhang, B., Cao, C., & Chen, Y. (2021). Consistency and Stability of SNPP ATMS Microwave Observations and COSMIC-2 Radio Occultation over Oceans. Remote Sensing, 13(18), 3754. https://doi.org/10.3390/rs13183754

Smith, J. W., Haynes, P. H., Maycock, A. C., Butchart, N., & Bushell, A. C. (2021). Sensitivity of stratospheric water vapour to variability in tropical tropopause temperatures and large-scale transport. Atmospheric Chemistry and Physics, 21(4), 2469–2489. https://doi.org/10.5194/acp-21-2469-2021

Stocker, M., Ladstädter, F., & Steiner, A. K. (2021). Observing the climate impact of large wildfires on stratospheric temperature. Scientific Reports, 11(1), 22994. https://doi.org/10.1038/s41598-021-02335-7

Yu, P., Davis, S. M., Toon, O. B., Portmann, R. W., Bardeen, C. G., Barnes, J. E., Telg, H., Maloney, C., and Rosenlof, K. H. (2021). Persistent Stratospheric Warming Due to 2019–2020 Australian Wildfire Smoke. Geophys. Res. Letters, 48(7), e2021GL092609. https://doi.org/10.1029/2021GL092609

Zambri, B., Solomon, S., Thompson, D. W. J., & Fu, Q. (2021). Emergence of Southern Hemisphere stratospheric circulation changes in response to ozone recovery. Nature Geoscience, 14(9), 638–644. https://doi.org/10.1038/s41561-021-00803-3

Zou, C.-Z., Xu, H., Hao, X., & Fu, Q. (2021). Post-millennium atmospheric temperature trends observed from Satellites in stable orbits. Geophys. Res. Letters, 48(13), e2021GL093291. https://doi.org/10.1029/2021GL093291

2020

Ho, S., Anthes, R. A., Ao, C. O., Healy, S., Horanyi, A., Hunt, D., et al. (2020). The COSMIC/FORMOSAT-3 Radio Occultation Mission after 12 Years: Accomplishments, Remaining Challenges, and Potential Impacts of COSMIC-2. Bull. Amer. Meteor. Soc., 101(7), E1107–E1136. https://doi.org/10.1175/BAMS-D-18-0290.1

Mitchell, D. M., Lo, Y. T. E., Seviour, W. J. M., Haimberger, L., and Polvani, L. M. (2020). The vertical profile of recent tropical temperature trends: Persistent model biases in the context of internal variability, Environmental Research Letters, https://doi.org/10.1088/1748-9326/ab9af7

Steiner, A. K., F. Ladstädter, W. J. Randel, A. C. Maycock, Q. Fu, C. Claud, H. Gleisner, L. Haimberger, S.-P. Ho, P. Keckhut, T. Leblanc, C. Mears, L. Polvani, B. Santer, T. Schmidt, V. Sofieva, R. Wing, and C.-Z. Zou (2020), Observed temperature changes in the troposphere and stratosphere from 1979 to 2018, J. Climate, 33(19), 8165–8194. https://doi.org/10.1175/JCLI-D-19-0998.1 (ATC community paper).

Steiner, A. K., Ladstädter, F., Ao, C. O., Gleisner, H., Ho, S.-P., Hunt, D., et al. (2020). Consistency and structural uncertainty of multi-mission GPS radio occultation records. Atmos. Meas. Tech., 13(5), 2547–2575. https://doi.org/10.5194/amt-13-2547-2020

von Schuckmann, K., L. Cheng, M. D. Palmer, J. Hansen, C. Tassone, V. Aich, S. Adusumilli, H. Beltrami, T. Boyer, F. J. Cuesta-Valero, D. Desbruyères, C. Domingues, A. García-García, P. Gentine, J. Gilson, M. Gorfer, L. Haimberger, M. Ishii, G. C. Johnson, R. Killik, B. A. King, G. Kirchengast, N. Kolodziejczyk, J. Lyman, B. Marzeion, M. Mayer, M. Monier, D. P. Monselesan, S. Purkey, D. Roemmich, A. Schweiger, S. I. Seneviratne, A. Shepherd, D. A. Slater, A. K. Steiner, F. Straneo, M.-L. Timmermans, and S. E. Wijffels (2020), Heat stored in the Earth system: where does the energy go? Earth Syst. Sci. Data, 12, 2013–2041, https://doi.org/10.5194/essd-12-2013-2020

2012 – 2020

Ding, Q., & Fu, Q. (2017). A warming tropical central Pacific dries the lower stratosphere. Climate Dynamics. https://doi.org/10.1007/s00382-017-3774-y

Funatsu, B. M., Claud, C., Keckhut, P., Hauchecorne, A., & Leblanc, T. (2016). Regional and seasonal stratospheric temperature trends in the last decade (2002–2014) from AMSU observations. Journal of Geophysical Research: Atmospheres, 2015JD024305. https://doi.org/10.1002/2015JD024305

Garfinkel, C. I., Son, S.-W., Song, K., Aquila, V., & Oman, L. D. (2017). Stratospheric variability contributed to and sustained the recent hiatus in Eurasian winter warming. Geophysical Research Letters, 44(1), 2016GL072035. https://doi.org/10.1002/2016GL072035

Hauchecorne, A. Blanot, L., Wing, R., Keckhut, P., Khaykin, S., Bertaux, J-L., Meftah, M., Claud, C., & Sofieva, V. (2018). A new MesosphEO dataset of temperature profiles from 35 to 85 km using Rayleigh scattering at limb from GOMOS/ENVISAT daytime observations. Atmospheric Measurement Techniques Discussion, https://doi.org/10.5194/amt-2018-241

Ho, S.-P., Peng, L., & Vömel, H. (2017). Characterization of the long-term radiosonde temperature biases in the upper troposphere and lower stratosphere using COSMIC and Metop-A/GRAS data from 2006 to 2014. Atmospheric Chemistry and Physics, 17(7), 4493–4511. https://doi.org/10.5194/acp-17-4493-2017

Ivy, D. J., Solomon, S., & Rieder, H. E. (2015). Radiative and Dynamical Influences on Polar Stratospheric Temperature Trends. Journal of Climate. https://doi.org/10.1175/JCLI-D-15-0503.1

Ivy, D. J., Solomon, S., Calvo, N., & Thompson, D. W. J. (2017). Observed connections of Arctic stratospheric ozone extremes to Northern Hemisphere surface climate. Environmental Research Letters, 12(2), 024004

Khaykin, S. M., Funatsu, B. M., Hauchecorne, A., Godin-Beekmann, S., Claud, C., Keckhut, P., et al. (2017). Postmillennium changes in stratospheric temperature consistently resolved by GPS radio occultation and AMSU observations. Geophysical Research Letters, 44(14), 2017GL074353. https://doi.org/10.1002/2017GL074353

Li, J., Thompson, D. W. J., Barnes, E. A., & Solomon, S. (2017). Quantifying the Lead Time Required for a Linear Trend to Emerge from Natural Climate Variability. Journal of Climate. https://doi.org/10.1175/JCLI-D-16-0280.1

Long, C. S., Fujiwara, M., Davis, S., Mitchell, D. M., & Wright, C. J. (2017). Climatology and interannual variability of dynamic variables in multiple reanalyses evaluated by the SPARC Reanalysis Intercomparison Project (S-RIP). Atmos. Chem. Phys., 17(23), 14593–14629. https://doi.org/10.5194/acp-17-14593-2017

Maycock, A. C. (2016). The contribution of ozone to future stratospheric temperature trends. Geophysical Research Letters, 2016GL068511. https://doi.org/10.1002/2016GL068511

Maycock, A. C., & Hitchcock, P. (2015). Do split and displacement sudden stratospheric warmings have different annular mode signatures? Geophysical Research Letters, 2015GL066754. https://doi.org/10.1002/2015GL066754

Maycock, A. C., Randel, W. J., Steiner, A. K., Karpechko, A. Y., Cristy, J., Saunders, R., Thompson, D. W. J., Zou, C.-Z., Chrysanthou, A., Abraham, N. L., Akiyoshi, H., Archibald, A. T., Butchart, N., Chipperfield, M., Dameris, M., Deushi, M., Dhomse, S., Genova, G. D., Jöckel, P., Kinnison, D. E., Kirner, O., Ladstädter, F., Michou, M., Morgenstern, O., O’Connor, F., Oman, L., Pitari, G., Plummer, D. A., Revell, L. E., Rozanov, E., Stenke, A., Visioni, D., Yamashita, Y. and Zeng, G. (2018). Revisiting the mystery of recent stratospheric temperature trends. Geophysical Research Letters. https://doi.org/10.1029/2018GL078035 (Frontier article).

McLandress, C., Shepherd, T. G., Jonsson, A. I., von Clarmann, T., & Funke, B. (2015). A method for merging nadir-sounding climate records, with an application to the global-mean stratospheric temperature data sets from SSU and AMSU. Atmospheric Chemistry and Physics, 15(16), 9271–9284. https://doi.org/10.5194/acp-15-9271-2015

Mears, C. A., & Wentz, F. J. (2017). A Satellite-Derived Lower-Tropospheric Atmospheric Temperature Dataset Using an Optimized Adjustment for Diurnal Effects. Journal of Climate, 30(19), 7695–7718. https://doi.org/10.1175/JCLI-D-16-0768.1

Ming, A., Maycock, A. C., Hitchcock, P., & Haynes, P. (2017). The radiative role of ozone and water vapour in the annual temperature cycle in the tropical tropopause layer. Atmos. Chem. Phys., 17(9), 5677–5701. https://doi.org/10.5194/acp-17-5677-2017

Nash, J., & Saunders, R. (2013). A review of Stratospheric Sounding Unit radiance observations in support of climate trends investigations and reanalysis (Met Office Technical Report No. 586) (pp. 58).

Nash, J., & Saunders, R. (2015). A review of Stratospheric Sounding Unit radiance observations for climate trends and reanalyses. Quarterly Journal of the Royal Meteorological Society, 141(691), 2103–2113. https://doi.org/10.1002/qj.2505

Polvani, L. M., Abalos, M.; Garcia, R., Kinnison, D. & Randel, W. J. (2018). Significant weakening of Brewer-Dobson circulation trends over the 21st century as a consequence of the Montreal Protocol. Geophys. Res. Lett., 45, 401–409. https://doi.org/10.1002/2017GL075345

Polvani, L. M., Wang, L., Aquila, V., Waugh, D.W., & Randel, W. J. (2018). The impact of ozone-depleting substances on tropical upwelling, as revealed by the absence of lower-stratospheric cooling since the late 1990s. J. Climate, 30, 2523–2534. https://doi.org/10.1175/JCLI-D-16-0532

Randel, W. J., Smith, A. K., Wu, F., Zou, C.-Z., & Qian, H. (2016). Stratospheric temperature trends over 1979-2015 derived from combined SSU, MLS and SABER satellite observations. Journal of Climate. https://doi.org/10.1175/JCLI-D-15-0629.1

Randel, W. J., Polvani, L., Wu, F., Kinnison, D. E., Zou, C.-Z., & Mears, C. (2017). Troposphere-Stratosphere Temperature Trends Derived From Satellite Data Compared With Ensemble Simulations From WACCM. Journal of Geophysical Research: Atmospheres, 122(18), 2017JD027158. https://doi.org/10.1002/2017JD027158

Randel, W. J. (2018). The seasonal fingerprint of climate change. Science, 361, 227–228. doi:10.1126/science.aat9097

Santer, B. D., Solomon, S., Pallotta, G., Mears, C., Po-Chedley, S., Fu, Q., et al. (2016). Comparing tropospheric warming in climate models and satellite data. Journal of Climate. https://doi.org/10.1175/JCLI-D-16-0333.1

Santer, B. D., Fyfe, J. C., Pallotta, G., Flato, G. M., Meehl, G. A., England, M. H., et al. (2017). Causes of differences in model and satellite tropospheric warming rates. Nature Geosci, 10(7), 478–485

Santer, B. D., Solomon, S., Wentz, F. J., Fu, Q., Po-Chedley, S., Mears, C., et al. (2017). Tropospheric Warming Over The Past Two Decades. Scientific Reports, 7(1), 2336. https://doi.org/10.1038/s41598-017-02520-7

Santer, B. D., Po-Chedley, S., Zelinka, M. D., Cvijanovic, I., Bonfils, C., Durack, P. J., Fu, Q., Kiehl, J., Mears, C., Painter, J., Pallotta, G., Solomon, S., Wentz, F. J., & Zou, C.-Z. (2018). Human influence on the seasonal cycle of tropospheric temperature. Science, 361(6399), eaas8806. https://doi.org/10.1126/science.aas8806

Scherllin-Pirscher, B., Randel, W. J., & Kim, J. (2017). Tropical temperature variability and Kelvin-wave activity in the UTLS from GPS RO measurements. Atmospheric Chemistry and Physics, 17(2), 793–806. https://doi.org/10.5194/acp-17-793-2017

Schmidt, T., Schoon, L., Dobslaw, H., Matthes, K., Thomas, M., & Wickert, J. (2016). UTLS temperature validation of MPI-ESM decadal hindcast experiments with GPS radio occultations. Meteorologische Zeitschrift, 25(6), 673–683. https://doi.org/10.1127/metz/2015/0601

Seidel, D. J., Li, J., Mears, C., Moradi, I., Nash, J., Randel, W. J., et al. (2016). Stratospheric temperature changes during the satellite era. Journal of Geophysical Research: Atmospheres, 121(2), 2015JD024039. https://doi.org/10.1002/2015JD024039

Shultz, D. (2018), Satellite observations validate stratosphere temperature models, Eos, https://doi.org/10.1029/2018EO109113, published on 21 November 2018.

Steiner, A. K., Lackner, B. C., & Ringer, M. A. (2018). Tropical convection regimes in climate models: evaluation with satellite observations. Atmospheric Chemistry and Physics, 18, 4657–4672, https://doi.org/10.5194/acp-18-4657-2018

Thompson, D. W. J., Seidel, D. J., Randel, W. J., Zou, C.-Z., Butler, A. H., Mears, C., et al. (2012). The mystery of recent stratospheric temperature trends. Nature, 491(7426), 692–697. https://doi.org/10.1038/nature11579

Wilhelmsen, H., Ladstädter, F., Scherllin-Pirscher, B., & Steiner, A. K. (2018). Atmospheric QBO and ENSO indices with high vertical resolution from GNSS radio occultation temperature measurements. Atmos. Meas. Tech., 11(3), 1333–1346. https://doi.org/10.5194/amt-11-1333-2018

Zou, C.-Z., Qian, H., Wang, W., Wang, L., & Long, C. (2014). Recalibration and merging of SSU observations for stratospheric temperature trend studies. Journal of Geophysical Research: Atmospheres, 119(23), 2014JD021603. https://doi.org/10.1002/2014JD021603

Zou, C.-Z., & Qian, H. (2016). Stratospheric Temperature Climate Data Record from Merged SSU and AMSU-A Observations. Journal of Atmospheric and Oceanic Technology, 33(9), 1967–1984. https://doi.org/10.1175/JTECH-D-16-0018.1

Zou, C.-Z., Goldberg, M. D., & Hao, X. (2018). New generation of U.S. satellite microwave sounder achieves high radiometric stability performance for reliable climate change detection. Science Advances, 4(10), eaau0049. https://doi.org/10.1126/sciadv.aau0049

SPARC activity reports:
  • SPARC Newsletter No. 56 (2021), p. 14: Current state of atmospheric temperature trends from observations – Milestone achieved by the Atmospheric Temperature Changes and their Drivers (ATC) Activity, A. K. Steiner.
  • SPARC Newsletter No. 47 (2016), p. 36: Report on the 1st Atmospheric Temperature Changes and their Drivers (ARC) Activity Workshop, by Maycock A.C., A.K. Steiner, and B. Randel
  • SPARC Newsletter No. 45 (2015), p. 31: SPARC workshop on Stratospheric Temperature Trends, Randel, B., D. Seidel, and D. Thompson.

Website for further information

  • Presentations from the 1st ATC Workshop held in April 2016 in Graz Austria, are available on request.
  • Presentations from the 2nd ATC Workshop held in June 2018 in Paris, France, are available on request.
  • Presentations from the 3rd ATC Workshop held in on 31 May and 1 June 2022, Helsinki, Finland are available on request.