Increase of Extreme Drought over Ethiopia under Climate Warming

Asaminew Teshome,Jie Zhang

doi:10.1155/2019/5235429

Abstract

Recurrent extreme drought and flood in Ethiopia lead to more economic loss. This study examines change and trends of 21 climate extremes of temperature and precipitation over Ethiopia by using indices from the World Meteorological Organization (WMO) Expert Team on Climate Change Detection and Indices (ETCCDI). The analysis was based on the records of observed meteorological data and the future projected from the CMIP5 model under RCP 4.5 and RCP 8.5 scenarios. The results of the seasonal standardized rainfall anomaly and EOF analysis show a decreasing rainfall in JJAS season and significant variability in the FMAM season. The first mode of EOF in FMAM shows that 49.6% was mostly negative with a high amount of variability. The observed precipitation extreme of annual total precipitation (PRCPTOT), consecutive wet days (CWD), and the number of heavy precipitation days (R10) show a decreasing trend, and consecutive dry days (CDD) shows an increasing trend. Additionally, temperature extremes like tropical nights (TR20) and daily maximum and minimum temperatures show a significantly increasing trend. The projected precipitation extremes of CWD, PRCPTOT, very wet day annual total (R95p), and the number of heavy precipitation days (R10) show a decreasing trend. CDD shows longer periods of dryness and a substantial increase which is conducive to the increase of drought. The projected temperature extremes of the warm spell duration indicator (WSDI), daily maximum temperature (TXx) and daily minimum temperature (TNx), summer days (SU25), and tropical nights (TR20) show an increasing trend, while the diurnal temperature range shows a decreasing trend. The projected changes in temperature and precipitation extremes are likely to have significant negative impacts on various socioeconomic activities over Ethiopia. These results highlight the need for planning and developing effective adaptation strategies for disaster prevention.

Highlights

Warming of the climate system is unequivocal, and climate affects every aspect of nature and human life [1]
E contour-based seasonal rainfall analysis of FMAM and JJAS shows that, over northeastern, central, southern, and southeastern parts of the country, the seasonal rainfall is variable (Figures 2(a) and 2(b)). e probabilistic density function (PDF) plot of the standardized rainfall anomaly shows that near-normal-to-extreme drought events occurred over Ethiopia and the frequent droughts mainly occurred during FMAM and JJAS seasons
Climate change is associated with the significant reduction in rainfall and the increase in droughts that are already apparent in some parts of Ethiopia, and droughts resulted in loss of human life, livestock, and property, as well as migration of people [54]

Summary

Introduction

Warming of the climate system is unequivocal, and climate affects every aspect of nature and human life [1]. Recent reports by the Intergovernmental Panel on Climate Change (IPCC) indicated that the intensity and frequency of extremes are likely to increase over many areas including East Africa. E frequency and intensity of extremes like droughts, floods, and heat waves are expected to change as earth’s climate changes, and these changes could occur even with relatively small mean climate changes [1,2,3,4]. Ethiopia is one of the largest humanitarian aid beneficiaries in the world and experiences significant climateinduced drought and water-related stresses on crop and livestock productivity [5]. Prolonged exposure to high-temperature extremes can cause heat-related illness, including heat cramps, heat exhaustion, heat stroke, and death. Elevated temperatures have major consequences on livestock and terrestrial biota generally [8,9,10]

Methods

Results

Conclusion