Trends in daily observed temperature and precipitation extremes over three Ethiopian eco‐environments

Abstract

Ethiopia has wide eco-environmental diversity ranging from extreme heat at one of the lowest places in the world to one of the coolest summits in Africa. Associated with this environmental diversity and climate change, climatic extremes are expected to change over time and also vary across eco-environments in the country. This study was conducted to examine the trends of past precipitation and temperature extremes over three eco-environments in Ethiopia. The study involved analysis of 20 extreme indices computed from daily temperature and precipitation data spanning over 42 years . The climate data were obtained from 11 stations selected from three major eco-environments (pastoral, agropastoral and highland). The results indicated positive trends for maximum value of the maximum temperature (TXx), warm days (TX90p), warm nights (TN90p) and warm spell duration indicators (WSDI) and negative trends for cool days (TX10p), cool nights (TN10p) and cold spell duration indicators (CSDI) in more than 8 of the 11 stations studied. However, most of the trends were not significant at many of the stations and the significant trends were not uniquely differentiated by eco-environments. Unlike temperature extremes, precipitation extreme trends showed high variability among nearby stations within eco-environments and were not significant at many of the stations studied. It is concluded that trends of temperature and precipitation extremes vary considerably among stations located within a given eco-environment indicating that the response of local climate to global warming could be different in physiographically diverse regions.

Effects of long-term deforestation and remnant forests on rainfall and temperature in the Central Rift Valley of Ethiopia

“…The warming trend indicated in this study is consistent with previous studies that reported a warming trend in the Central Rift Valley (Kassie et al 2013;Mekasha et al 2013). However, the highland stations Butajira and Kulumsa, showed a significant decrease in the annual minimum temperature.…”

“…However, the highland stations Butajira and Kulumsa, showed a significant decrease in the annual minimum temperature. A similar result was also reported by Mekasha et al (2013) for Kulumsa station where it showed a decreasing tendency in daily minimum temperature during a similar study period. Generally, most previous studies reported a warming trends in Ethiopia over the past few decades for both maximum and minimum temperatures (McSweeney et al 2008;Taye and Zewdu 2012;Tesso et al 2012;Jury and Funk 2013).…”

Trend analysis of temperature and precipitation extremes in major grain producing area of China

“…The climate extreme indices recommended by ETCCDMI (Expert Team on Climate Change Detection and Indices) (Peterson and Manton, 2008) are used in this study, which have been developed as a suite of indices derived from daily temperature and precipitation data and used in many regions around the world (Dos Santos et al, 2011;Casanueva et al, 2014;Mekasha et al, 2014;Wu et al, 2014). According to the characteristics of the climate in the study area, we select 15 indices from ETCCDMI, including 8 temperature indices and 7 precipitation indices ( Table 1).…”

Regional Hydrological Cycle over the Red Sea in ERA-Interim

“…In this respect, further analysis of the precipitation variability using all available data will be desirable. We noted above that Mekasha et al (2014) and Kumar et al (2015) reported the growing intensity of heavy precipitation over the East African Rift Valley and the Arabian Peninsula. The mechanisms through which increased moisture export can affect precipitation over the adjacent continents are quite complicated, given that the moisture recycling in this region is modulated by various atmospheric processes in a heavily undersaturated atmosphere.…”

“…Nevertheless, moisture transports from the Red Sea and the Arabian Sea result in heavy precipitation events even over the hyperarid Arabian Peninsula (Kumar et al 2015). While Viste et al (2013) reported an intensification of drying conditions over northeastern Africa, Mekasha et al (2014) demonstrated that heavy precipitation events intensified over the last three decades, particularly in the East African Rift Valley.…”