Analysis of Current Climate Variability and Future Change in the Great Rift Valley Region of Ethiopia

Climate variability and change have significant direct and indirect consequences for crop production and nitrous oxide (N2O) emissions in rainfed agriculture-based developing countries, such as Ethiopia. This study aimed to understand and analyze the spatio-temporal dynamics of rainfall and temperature and the implications on crop production and N2O emission in the baseline (1988-2017) and future climate periods (2040 and 2060) based on six General Circulation Models (GCMs) under two emission scenarios, Shared Socioeconomic Pathways (SSP245 and SSP585), in the Great Rift Valley (GRV) of Ethiopia. Baseline variabilities and trends of annual and seasonal rainfall and temperature were analyzed. Projected changes in rainfall and temperature were evaluated. Rainfall onset and cessation, and length of growing periods (LGPs) were determined. The results indicated that there was a high rainfall variability and an increasing trend in rainfall and temperature in all seasons and sites. Future annual rainfall would increase by 24% in 2040 and by 66% in 2060. Annual maximum and minimum temperatures, respectively, are also expected to increase by 0.10 and 0.12°C in 2040 by 0.16 and 0.19°C in 2060. The LGP is expected to increase by 8 days in 2040, by 32 days in 2060. However, there is a spatial variability, ranging from 89 to 118 days in 2040 and from 115 to 157 days in 2060. In this context, designing location- and season-specific management options is crucial to reduce the negative effects of current climate variability and change.