| Autor: |
Lars Hoffmann, Jennifer Schröter, Roland Ruhnke, Peter Braesicke, Oliver Kirner, Michael Weimer |
| Rok vydání: |
2020 |
| Předmět: |
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| DOI: |
10.5194/egusphere-egu2020-2451 |
| Popis: |
Polar Stratospheric Clouds (PSCs) play a key role in explaining ozone depletion on largescales as well as on regional scales. Mountain waves can be formed in the lee of a mountainin a stably stratified atmosphere. They can propagate upwards into the stratosphere andinduce temperature changes in the order of 10 to 15 K. Thus, large PSCs localised around themountain ridge can be formed, leading to increased chlorine activation and subsequently toa larger ozone depletion. It was estimated that 30 % of the southern hemispheric PSCs canbe explained by mountain waves. However, for the direct simulation of mountain-waveinduced PSCs, the mountains have to be represented adequately in global chemistry climatemodels which was a challenge in the past due to too low horizontal resolution.The ICOsahedral Nonhydrostatic (ICON) modelling framework with its extension for Aerosolsand Reactive Trace gases (ART) includes a PSC scheme coupled to the atmospheric chemistryin the model. The PSC scheme calculates the formation of all three PSC types independentlyresulting in the calculation of the heterogeneous reaction rates of chlorine and brominespecies on the surface of PSCs. ICON-ART provides the possibility of local grid refinementwith two-way interaction. With this, the grid around a mountain can be refined so thatmountain waves can be directly simulated in this region with a feedback to the coarserglobal resolution.In this study, we show the formation of mountain-wave induced PSCs with ICON-ART for theexample of a mountain wave event in July 2008 around the Antarctic Peninsula. It isevaluated with satellite measurements of AIRS and CALIOP and its impact on chlorine andbromine activation as well as on the ozone depletion in the southern hemisphere areanalysed. We demonstrate that the effect of mountain-wave induced PSCs can berepresented in the coarser global grid by using local grid refinement with two-wayinteraction. Thus, this study bridges the gap between directly simulated mountain-waveinduced PSCs and their representation in a global simulation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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