Kotikot Susan M, Smithwick Erica A H, Greatrex Helen
Department of Geography, Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA, USA.
Department of Geography, Department of Statistics, Institute for Computational and Data Sciences, The Pennsylvania State University, University Park, PA, USA.
Sci Rep. 2024 Jun 5;14(1):12915. doi: 10.1038/s41598-024-63786-2.
Understanding local patterns of rainfall variability is of great concern in East Africa, where agricultural productivity is dominantly rainfall dependent. However, East African rainfall climatology is influenced by numerous drivers operating at multiple scales, and local patterns of variability are not adequately understood. Here, we show evidence of substantial variability of local rainfall patterns between 1981 and 2021 at the national and county level in Kenya, East Africa. Results show anomalous patterns of both wetting and drying in both the long and short rainy seasons, with evidence of increased frequency of extreme wet and dry events through time. Observations also indicate that seasonal and intraseasonal variability increased significantly after 2013, coincident with diminished coherence between ENSO (El Nino Southern Oscillation) and rainfall. Increasing frequency and magnitude of rainfall variability suggests increasing need for local-level climate change adaptation strategies.
了解当地降雨变率模式在东非备受关注，该地区农业生产力主要依赖降雨。然而，东非降雨气候学受到多种在多个尺度上起作用的驱动因素影响，当地的变率模式尚未得到充分理解。在此，我们展示了1981年至2021年期间东非肯尼亚国家和县级层面当地降雨模式存在显著变率的证据。结果表明，在长雨季和短雨季都出现了异常的湿润和干燥模式，且有证据显示极端湿润和干燥事件的频率随时间增加。观测还表明，2013年后季节性和季节内变率显著增加，这与厄尔尼诺南方涛动（ENSO）和降雨之间的相关性减弱相一致。降雨变率的频率和强度不断增加，表明越来越需要制定地方层面的气候变化适应策略。
