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| Titel |
Extreme future central European droughts in a high-resolution global climate model |
| VerfasserIn |
Rein Haarsma, Eveline C. van der Linden, Frank Selten, Gerard van der Schrier |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250149747
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| Publikation (Nr.) |
 EGU/EGU2017-14128.pdf |
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| Zusammenfassung |
| Future climate change is projected to induce strong central European summer drying. Using high resolution (~25 km) climate simulations we have investigated the occurrence of droughts at the end of the 21th century under a RCP4.5 emission scenario. Dynamic mechanisms and local feedbacks are responsible for a strong increase of extreme droughts in central Europe. This increase is much larger than for the standard (~150 km) resolution of the same model. The dynamical cause is a stronger anomalous high over the UK in late spring that induces enhanced subsidence with reduced precipitation. This reduces the soil moisture content, thereby pre-conditioning the occurrence of local feedbacks that enhance the drought conditions. These local feedbacks are a reduction of the evaporative fraction that induces an enhancement of surface temperature, increase of dry days and solar radiation. The pre-conditioning and enhancement by local feedbacks induce a clustering of extreme droughts and is a source of predictability. The extreme character of the droughts affects the ground water storage and the run-off in the following year. An additional effect of the increase of drought induced summer temperatures is that a larger fraction of the precipitation falls as heavy rain. |
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