Analysis of Climate Variability and Trends in Southern Ethiopia

Abrham Belay,John W Recha,Christopher Oludhe,Lydia A Olaka,Teferi Demissie,Zerihun Berhane,Dawit Solomon,Philip M Osano

doi:10.3390/cli9060096

Abstract

This study investigated the trends and variability of seasonal and annual rainfall and temperature data over southern Ethiopia using time series analysis for the period 1983–2016. Standard Anomaly Index (SAI), Coefficient of Variation (CV), Precipitations Concentration Index (PCI), and Standard Precipitation Index (SPI) were used to examine rainfall variability and develop drought indices over southern Ethiopia. Temporal changes of rainfall trends over the study period were detected using Mann Kendall (MK) trend test and Sen’s slope estimator. The results showed that the region experienced considerable rainfall variability and change that resulted in extended periods of drought and flood events within the study period. Results from SAI and SPI indicated an inter-annual rainfall variability with the proportions of years with below and above normal rainfall being estimated at 56% and 44% respectively. Results from the Mann Kendall trend test indicated an increasing trend of annual rainfall, Kiremt (summer) and Bega (dry) seasons whereas the Belg (spring) season rainfall showed a significant decreasing trend (p < 0.05). The annual rate of change for mean, maximum and minimum temperatures was found to be 0.042 °C, 0.027 °C, and 0.056 °C respectively. The findings from this study can be used by decision-makers in taking appropriate measures and interventions to avert the risks posed by changes in rainfall and temperature variability including extremes in order to enhance community adaptation and mitigation strategies in southern Ethiopia.

Highlights

Climate change is consideredone of the biggest challenges facing the world in the21st century [1,2,3]
The results showed an increasing trend of drought years with decreasing trends of both Belg and Kiremt rainfall patterns while changes in temperature showed an increasing trend
The major share of the annual rainfall was received in Kiremt (55.45%) and Belg (33.20%)

Summary

Introduction

Climate change is consideredone of the biggest challenges facing the world in the21st century [1,2,3]. The natural causes include changes in solar activities, orbital parameters and volcanic eruptions, while the anthropogenic causes arise from various activities that emit greenhouse gases [4]. To combat this global environmental problem, the United Nations Framework Convention on Climate Change (UNFCCC) approved the. The framework focuses on low carbon development strategies with policy obligations for all the countries to keep the level of global warming to below 2 degrees Celsius [5,6]. Climate change is severely affecting many developing countries whose main economic activities largely depend on climate-sensitive sectors with low adaptative capacity [7]

Methods

Results

Conclusion