E_179 Land-atmosphere interactions

The replication of the coastline a few kilometers inland by convective clouds on a summer day, the enhancement of precipitation over mountainous regions or potential changes in the precipitation regime following the deforestation in Amazonia are all examples of interactions between the land surface and the atmosphere. The aim of this course is to introduce and explain the effects of the land surface on the atmosphere, with a special focus on convection and precipitation, going from the small scales to the larger scales.
The lecture will start with a brief reminder on land surface processes and how they affect the atmosphere. It will then take a process-oriented perspective explaining the requirements for strong land-atmosphere coupling and the mechanisms behind this coupling. This will include topics such as landscape-induced shallow circulations, soil moisture-precipitation feedback, soil moisture-temperature feedback, heat lows and monsoons. Finally, the lecture will use the derived concepts to understand the role of land-atmosphere interactions in the past climate record as well as for future climate changes.

Aim:

After taking this course, a student should be able to understand when and why the land surface is important, how a change in the land surface might influence the atmosphere and the climate and what the uncertainties are.