Enhancement of East African Monsoon Long Rainfall (March to May) Variability from Weekly to Annual Scale by Climatic Extremes — Oak Academic Publishing
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Enhancement of East African Monsoon Long Rainfall (March to May) Variability from Weekly to Annual Scale by Climatic Extremes
School of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing, China
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Key Laboratory of Meteorological Disaster of Ministry of Education (KLME), Nanjing University of Information Science and Technology, Nanjing, China
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Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing, China
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School of Science and Technology, University of Rwanda, Kigali, Rwanda
1 School of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing, China
2 Key Laboratory of Meteorological Disaster of Ministry of Education (KLME), Nanjing University of Information Science and Technology, Nanjing, China
3 Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, Nanjing University of Information Science and Technology, Nanjing, China
4 School of Science and Technology, University of Rwanda, Kigali, Rwanda
As global warming increasingly affects vulnerable regions such as Central East Africa, it is crucial to understand future changes in rainfall variability to reduce vulnerability. Despite the importance of rainfall variability, it has received less attention compared to changes in mean and extreme rainfall. This study evaluates the amplification of synoptic (weekly) to annual variability of East African Monsoon (EAM) Long Rainfall (March to May) by climatic extremes. Using band-pass filtered daily rainfall data, we found that EAM rainfall variability is anticipated to increase by 20% - 60% across the region under global warming conditions. The majority of the intermodal variability in Long Rain EAM rainfall forecasting is explained by differences in mean rainfall. Our results show that the synoptic variability of Long Rain for EAM rainfall is likely to amplify, resulting in more extreme rainfall events and longer dry spells under global warming. This amplification is attributed to the warming of the Indian Ocean and the associated changes in atmospheric circulation patterns. The projected increase in synoptic to annual variability of Long Rain for EAM rainfall has significant implications for water resources management and agriculture in the region, challenging policymakers to develop adaptive strategies that can mitigate the impacts of these extreme events. This study emphasizes the potential impacts of projected climate changes in rainfall variability on the East African region at all periods and underscores the need for effective adaptation strategies to ensure sustainable development.
KeywordsSynoptic VariabilityEast Africa Monsoon Long RainGlobal WarmingAmplification
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