GASS Meetings and Reports


30 years after the start of GCSS (GEWEX Cloud System Study – that became GASS in 2011) and 20 years after the start of CFMIP (Cloud Feedback Model Intercomparison), a joint CFMIP-GASS conference on Clouds, Precipitation, Circulation and Climate Sensitivity was held in Paris from July 9 to 13, 2023. It brought together over 230 participants from all over the world. In addition to oral presentations and poster sessions, the meeting organized 9 breakout group discussions on GASS and/or CFMIP projects. Progress on the various projects since last year’s 3rd pan-GASS meeting was reviewed, and next steps were discussed. One of the results of this meeting is that several GASS projects are now explicitly addressing issues related to climate change (e.g. the response of cold-air outbreaks to global warming, the role of shallow convective organization in low-cloud feedbacks, or global warming experiments performed with km-scale global models). Finally, an award was given to 6 Early Career Scientists for outstanding oral or poster presentations. The meeting demonstrated the strong scientific momentum of the international community around the study of cloud processes and their role in climate and climate change.


The 3rd Pan-GASS conference, Understanding and Modeling Atmospheric Processes (UMAP 2022), took place 25–29 July, 2022 in Monterey, CA, USA. UMAP 2022 aims to bring together weather and climate scientists, including both observationalists and modelers, to discuss the key issues of atmospheric science. The program will include all aspects and methods of model development from deterministic numerics to stochastic forcing; process modeling to parametrization; observational constraints to diagnostic techniques; and idealized modeling to operational forecasting and climate predictions. The purpose of the conference is to discuss progress in understanding atmospheric processes and representing them in models, to coordinate current initiatives and make plans for the future.

For a video impression* of the three GEWEX meetings (3rd Pan-GASS, 2022 Pan-GEWEX and GEWEX SSG 34B) in Monterey, CA, USA, click here.

* Prepared by Yike Xu from the University of Arizona for, and published by, the International GEWEX Project Office under a Creative Commons Attribution 4.0 IGO License (CC BY-ND 4.0 IGO, (

The 2nd Pan-GASS conference took place 26 Feb-2 Mar 2018 in Lorne, near Melbourne, Victoria, Australia. The purpose of the conference was to plan and discuss future GASS initiatives and the future direction of research supporting atmospheric model development globally. There was a wide-ranging program of posters and presentations covering the key challenges of current and next generation atmospheric model development.

The 1st Pan-GASS Conference was held on 10-14 September 2012 in Boulder, Colorado, USA, and focused on observing, understanding, and modeling atmospheric physical processes.

GASS Annual Report, October 2012

This report details GASS activities from August 2011 to October 2012, reviewing the eleven planned and ongoing GASS projects and providing a brief overview of the 1st Pan-GASS Meeting in October 2012.

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