Articles | Volume 4, issue 2
https://doi.org/10.5194/wcd-4-381-2023
© 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-4-381-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
The impact of the Agulhas Current system on precipitation in southern Africa in regional climate simulations covering the recent past and future
Helmholtz-Zentrum Hereon, Institute of Coastal Systems – Analysis and Modeling, Max-Planck-Straße 1, 21502 Geesthacht, Germany
Eduardo Zorita
Helmholtz-Zentrum Hereon, Institute of Coastal Systems – Analysis and Modeling, Max-Planck-Straße 1, 21502 Geesthacht, Germany
Birgit Hünicke
Helmholtz-Zentrum Hereon, Institute of Coastal Systems – Analysis and Modeling, Max-Planck-Straße 1, 21502 Geesthacht, Germany
Ioana Ivanciu
GEOMAR Helmholtz Centre for Ocean Research Kiel, 24105 Kiel, Germany
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Our study analyses extreme precipitation over southern Africa in regional high-resolution atmospheric simulations of the past and future. We investigated heavy precipitation over Southern Africa, coastal South Africa, Cape Town, and the KwaZulu-Natal province in eastern South Africa. Coastal precipitation extremes are projected to intensify, double in intensity in KwaZulu-Natal, and weaken in Cape Town. Extremes are not projected to occur more often in the 21st century than in the last decades.
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Short summary
As stated by the IPCC, southern Africa is one of the two land regions that are projected to suffer from the strongest precipitation reductions in the future. Simulated drying in this region is linked to the adjacent oceans, and prevailing winds as warm and moist air masses are transported towards the continent. Precipitation trends in past and future climate can be partly attributed to the strength of the Agulhas Current system, the current along the east and south coasts of southern Africa.
As stated by the IPCC, southern Africa is one of the two land regions that are projected to...