Joint Seminar: Atmospheric Deserts: What Are They and Why Do They Matter?
Heat waves, dust events, and severe thunderstorms are weather phenomena, that can directly impact human health, infrastructure, ecosystems and economy. Although these phenomena are often investigated separately, they may share a connection trough "atmospheric deserts''. Atmospheric deserts are a concept that our group recently introduced. They are air masses originating from the hot, dry, and deep convective boundary layers of desert and arid regions, which can be transported over thousands of kilometres by the large scale flow and still remain distinct. Due to their distinct (thermodynamic) properties they can modify the vertical profiles in the target regions and therefore influence the local weather.
We analyse atmospheric deserts using a direct detection method based on Lagrangian trajectories (LAGRANTO) and atmospheric reanalysis data (ERA5). Based on statistical investigation of the 2-year period from May 2022 to April 2024, and a detailed analysis of a case study in June 2022, we gained insights into the properties, modifications and consequences of atmospheric deserts. They occur frequently in Europe (up to 60% of the time in some regions), can cover up to 72% of land-cells in Europe, and last a few days on average. They can form a lid, which is typically short-lived, so that it is unlikely for them to cause heat waves. The probability of lightning near the atmospheric desert's edge is notably increased, but the probability of thunderstorms in their centres is not simply reduced due to the presence of the lid, but influenced differently dependent on the region.
Datum
29.10.2025
Uhrzeit
13:30 h
Ort
- Bundesstr. 53, room 022/023
- Seminar Room 022/023, Ground Floor, Bundesstrasse 53, 20146 Hamburg, Hamburg