Implications of climate change on grain yield of sorghum and millet over selected areas in Uganda

Climate change undoubtedly raises serious productivity and livelihood challenges in Uganda’s socio-ecological systems, which are dominated by smallholder farmers practising rainfed agriculture. While sorghum and millet are some of the key food security crops in Uganda’s socioecological systems, they have received suboptimal attention with re-spect to how they will be affected by climate change. In this study, we investigated patterns of climate change and its effect on yields of sorghum and millet in Soroti and Gulu areas of Uganda on a medium timescale of up to 2040. Downscaling and projections of future climatic conditions up to 2040 was undertaken using the PRECIS Model focussing on rainfall and temperature. Projected daily temperature and rainfall conditions were incorporated into Aqua-Crop and Penman Grindley Soil moisture balance model to simulate sorghum and millet yields for Soroti and Gulu, respectively. Results shows projected rainfall increase in Soroti, while for Gulu, a slight decrease is anticipated by 2040. In Soroti, sorghum yields are expected to respond positively to rainfall with yields increasing by up to 35% by 2040. The highest increments are second season (SON) in comparison to the first season (MAM) crops. Millet will experience dismal changes in yields 2.6%, which are projected to be negative, but tending towards red as the short rains (SON) increased. Surprisingly, there was a decline in the annual minimum and maximum temperature of 0.3 oC and 1.0 oC, respectively. More attention needs to be paid to stabilizing millet production including optimization of water use. Keywords: Climate change, crop yields, Gulu, sorghum, Soroti, Uganda