Observed Changes in Meteorological Drought Events during 1981–2020 over Rwanda, East Africa

Jacqueline Uwimbabazi,Yuanshu Jing,Vedaste Iyakaremye,Brian Ayugi,Irfan Ullah

doi:10.3390/su14031519

Abstract

Drought is one of the most complex natural phenomena affecting the life and livelihood of people, especially in the current time of human-induced climate change. This research employs ground-based observations to assess the recent spatiotemporal characteristics of meteorological drought events over Rwanda. The drought is examined based on the Standardized Precipitation Evapotranspiration Index (SPEI) and Standardized Precipitation Index (SPI) at seasonal and annual time scales from 1981 to 2020. The Man–Kendal test was used to evaluate the trends in rainfall, temperature, and SPEI values at the annual scale and during the March to May (MAM) and October to December (OND) seasons. The analysis revealed nonsignificant trends in annual (8.4 mm/decade), MAM (−3.4 mm/decade), and OND (4.5 mm/decade) rainfall, while an apparent significant increasing trend in surface air temperature was obtained during the MAM (0.19 °C/decade), OND (0.2 °C/decade), and annual (0.23 °C/decade) time slices. Overall, the SPEI characteristics indicated that the country is more prone to moderate drought events than severe and extreme drought events during MAM and OND seasons. However, the intensity, duration, and frequency differ spatially among seasons. The findings of this study inform policy and decision-makers on the past experienced drought behavior, which can serve as a baseline for future drought mitigation and adaptation plans.

Highlights

Introduction iationsClimate change and the high population growth rate are increasingly becoming major factors that hinder the sustainability of natural ecosystem conservation as well as human resource development
The result indicates that the country exhibits a bimodal rainfall pattern with the long rainy season from March to May (MAM) and the short rainy season from October to December (OND)
The comprehensive assessment of the historical meteorological drought could help better plan and mitigate such hazards. It is in this regard, the present study attempted to evaluate historical characteristics of meteorological drought events at various locations in Rwanda based on Standardized Precipitation Evapotranspiration Index (SPEI) and Standardized Precipitation Index (SPI) indices at seasonal and annual time scales from 1981 to 2020

Summary

Introduction

Climate change and the high population growth rate are increasingly becoming major factors that hinder the sustainability of natural ecosystem conservation as well as human resource development. In the 21st century, where human-induced climate change is altering drought characteristics, drought may no longer be regarded as a natural hazard. East Africa has frequently experienced severe and prolonged drought events leading to electric shortages and profound impacts on agricultural activities [5,6]. East African member countries, including Rwanda, depend heavily on the rain-fed agriculture that is being impacted by the changing climate [6].

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Discussion

Conclusion