Atmospheric Circulation (Prof. Sebastian Schemm)
Overview and News
High-resolution global climate simulation with ICON and two two-way nests over the Gulf Stream. Shown is the wind speed at the 300 hPa level.
The Atmospheric Circulation group was an ERC Starting Grant (2000–2024) supported research group led by Prof. Sebastian Schemm. It consisted of four postdoctorcal researchers, five main- plus two co-supervised PhD students, two student research assistant and supervised a total of 14 MA theses, 8 BA theses and 6 semester theses.
Its research focus on weather and climate dynamics, high-resolution atmospheric modeling and machine learning. This is done by modeling at different complexity, the use of observations, deep learning techniques and theory and the development of diagnostic tools in particular online diagnostics for high-resolution weather and climate models.
Recently, we have been working on the development of purely machine learning-based basic models for the climate system, for example, as part of the external page Swiss AI initiative, external page ECMWF's WeatherGenerator and as a means for high-resolution downscaling. More details can be found on the research page and below.
- More information about our research on the individual project pages.
- List of group members
- List of publications
- List of Bachelor and Master thesis
News
For details on our publications see bottom of this page.
New projects
- (2025) HiRAD-Gen (High-Resolution Atmospheric Downscaling Using Generative Machine Learning Models) funded by external page PASC will start on 1. Jan. 2025
- (2024) We are an associated partner in the EU-funded Horizon project called external page WeatherGenerator led by ECMWF.
- (2024) external page Swiss AI has started and together with SAM and SPCL we aim to develope a novel foundation model for the climate system.
- (2023) An ETH collaborative project grant jointly with ETH's Seminar for Applied Mathematics (group of Mishra Siddhartha) on machine learning-enhanced Bayesian inversion for turbulence modeling was granted. More details can be found on the project page.
- (2023) Our ETH-Weizmann Bridge project proposal was funded, we look forward to our collaboration with external page Yohai Kaspi, external page Shira Raveh-Rubin at external page Weizmann Institute and the atmospheric dynamics group at ETH.
- (2022) A newly external page SNSF funded research project will allow us to investigate how storm tracks will change in high-resolution simulations of future climates. More details can be found on the project page.
- (2022) Together with the Swiss Data Science Center (external page SDSC), we explore how to use machine learning to accelerated high-resolution weather and climate models and subgrid-scale physics. More details on the project page.
Activities:
- Jan Zibell and Nora Zilibotti presented their research at the external page 20th Cyclone Workshop in St. Sauveur, Quebec, Canada.
- Two new publications from our external page SNSF funded project with external page Alejandro Hermoso as lead author. The first is a detailed analysis of the dynamical mechanisms underlying the recent intensification trend of the North Atlantic jet stream (external page Journal of Climate) and the second presents a deep-learning method to disentangle forced trends in the North Atlantic jet from natural variability (external page JGR-A) (August 2024).
- The final statement of the external page EVE conference held in Berlin (3-7 July 2023) is now external page available.
- The group presented many of their research projects at the external page 2022 EMS Annual meeting [external page EMS2022-419, external page EMS2022-276, external page EMS2022-40]
- The external page 2022 storm track workshop took place on Oléron Island, France (29 May to 3 June 2022). We presented our work on idealized external page storm tracks in future climates.
- Stefan Rüdisühli and Katherine Osterrried (C2SM) participated in the external page CSCS/NVIDIA GPU Hackathon [September 2020]. A short article about how the event unfolded: "Following the air on GPUs".
- The external page EGU has launched an international not-for-profit scientific journal external page Weather and Climate Dynamics and Sebastian Schemm serves as Co-Editor of this open-access journal, which is dedicated to the publication and public discussion of high-quality research on dynamical processes in the atmosphere [August 2019].
Other news
- The Jetstream and our research featured in an external page NZZ article.
- Bjorn Stevens wrote an external page AGU EOS Editor highlight summary of our recent study on a persistent storm track bias [March 2023].
- Raphael Portmann wrote a behind the paper blog entry on external page Nature's community platform [October 2022] about his recent work on external page large-scale afforestation and deforestation.
- In June 2022 the D-USYS conference took place in Davos, with a contribution on Data Assimilation by our group.
- Research and family combined [ETH News Item, August 2020]
- Our group is an associated member of the ETH AI center, which offers Ph.D. and postdoc fellowships. Get in contact with us if you consider applying. [ETH AI center, December 2020]
- At the interface between weather and climate [USYS News Item, March 2020]
- European Meteorological Society Young Scientist Award awarded to Sebastian Schemm [USYS News Item, external page EMS News, June 2019]
New publications from the group
- Influence of adiabatic and diabatic processes on the jet stream: The influence of adiabatic and diabatic processes on the midlatitude circulation is a formidable research question, especially considering their projected changes under global warming. This new study external page published in the Quarterly Journal of the Royal Meteorological Society presents the prospects, merits and caveats of a potential vorticity (PV) gradient perspective as a means to disentangle the contributions of adiabatic and diabatic processes affecting the midlatitude circulation. We outline our method in two case studies of jet streak evolution in a simulation with 1.1 km grid spacing performed with the GPU-enabled numerical weather prediction model COSMO featuring online air parcel trajectories that we developed last year. [June 2023]
- [Editor Highlight] Journal of Advances in Modeling Earth Systems: Generations of climate models exhibit biases in their representation of North Atlantic storm tracks, which tend to be too far near the equator and too zonal. Additionally, models have difficulties simulating explosive cyclone growth. This study explores the hypothesis that diabatic processes on the storm scale are one root cause of all three biases and that kilometer-scale models have the potential to overcome it. external page Toward eliminating the decades-old “too zonal and too equatorward” storm-track bias in climate models. [Feb 2023] Read also the external page EOS.org highlight.
- Weather and Climate Dynamics: For the North Atlantic storm track, Coupled Model Intercomparison Project (CMIP) data indicate a tripole pattern of change under the RCP8.5 scenario. In this study, we reproduce the patterns by introducing local asymmetry in a zonally symmetric ICON aquaplanet simulation and examine the response of storm tracks to global warming downstream of the SST asymmetry. We find that regionally baroclinic conversion has the largest impact, while diabatic processes are of first order importance on the global scale. The lifetime of cyclones is decreasing and so are their numbers, but the most intense cyclones are becoming more intense. The study appears in external page EGU's Weather and Climate Dynamics. [May 2022]
- [Featured Article] Cloud-circulation interactions: Clouds are not passively moved in the atmosphere by the wind. Instead, clouds actively influence the flow field in their immediate vicinity. In this study, the flow field generated by clouds is quantified. It is shown that clouds create a flow that is directed against the direction of the wind in which they grow. Hence, clouds propagate more slowly than a passive object, and they are more stationary. This can influence the regional cloud and precipitation distribution. In this article external page published in the Quarterly Journal of the Royal Meteorological Society, we outline how to quantify the circulation influence of clouds.[February 2021] [external page Wiley Twitter]