Articles | Volume 4, issue 3
https://doi.org/10.5194/wcd-4-725-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-4-725-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
31 Aug 2023
Research article |
| 31 Aug 2023
| 31 Aug 2023
Adverse impact of terrain steepness on thermally driven initiation of orographic convection
Matthias Göbel
CORRESPONDING AUTHOR
Department of Atmospheric and Cryospheric Sciences, University of Innsbruck, Innsbruck, Austria
Regional Office Salzburg and Upper Austria, GeoSphere Austria, Salzburg, Austria
Stefano Serafin
Department of Meteorology and Geophysics, University of Vienna, Vienna, Austria
Mathias W. Rotach
Department of Atmospheric and Cryospheric Sciences, University of Innsbruck, Innsbruck, Austria
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Short summary
On summer days over mountains, upslope winds transport moist air towards mountain tops and beyond, making local rain showers more likely. We use idealized simulations to investigate how mountain steepness affects this mechanism. We find that steeper mountains lead to a delayed onset and lower intensity of the storms, because less moisture accumulates over the ridges and the thermal updraft zone at the top is narrower and thus more prone to the intrusion of dry air from the environment.
On summer days over mountains, upslope winds transport moist air towards mountain tops and...
