EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

The role of the Laurentide ice-sheet topography in the Alpine hydro-climate at glacial times

Patricio Velasquez1,2,3, Martina Messmer2,3, and Christoph C. Raible2,3
Patricio Velasquez et al.
  • 1Institute for Atmospheric and Climate Science, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland (
  • 2Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
  • 3Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland

In this study, we investigate the sensitivity of the glacial Alpine hydro-climate to changes of the Laurentide ice sheet (LIS). Bridging the scale gap by using a chain of global and regional climate models, we perform sensitivity simulations of up to 2 km horizontal resolution over the Alps for the Last Glacial Maximum and the Marine Isotope Stage 4. In winter, we find wetter conditions in the southern part of the Alps during glacial conditions compared to present day, to which dynamical processes, i.e.  changes in the wind speed and direction, substantially contribute. During summer, we find the expected drier conditions in most of the Alpine region during glacial conditions, as thermodynamics suggests drier conditions under lower temperatures. The sensitivity simulations of the LIS changes show that an increase of the ice-sheet thickness leads to a significant intensification of glacial Alpine hydro-climate conditions, which is mainly explained by dynamical processes. The findings demonstrate that the Laurentide ice-sheet topography plays an important role in regulating the Alpine hydro-climate and thus permits a better understanding of the precipitation patterns in the complex Alpine terrain at glacial times.

How to cite: Velasquez, P., Messmer, M., and Raible, C. C.: The role of the Laurentide ice-sheet topography in the Alpine hydro-climate at glacial times, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-1635,, 2022.


Display file

Comments on the display

to access the discussion