Projected temperature and rainfall in the semi-arid Lokere and Lokok catchments, northeastern Uganda

Trends in global warning over the past decades have been predicted to increase in the 21st Century, causing concerns for disaster preparedness in arid and semi-arid regions. This study utilized downscaled district level future temperature and rainfall scenarios for the semi-arid Lokok and Lokere Catchments in eastern Uganda, from 20 IPCC climate models embedded in the Agricultural Model Intercomparison and Improvement Project (AgMIP). The three periods are 2010-2039 (early century); 2040-2069 (midcentury), and 2070-2099 (end-century). The delta method, using a script provided in the AgMIP protocol, was applied in downscaling climate scenarios. Seasonal (DJF, MAM, JJA and SON) and annual means of station and the Catchments scale ensembles of minimum (Tmin), maximum temperature (Tmax), and rainfall for each of the three periods were computed and compared with 1980-2009 as the baseline period. Temperature is projected to increase, and change in Tmin would be higher than change in Tmax. Tmax in the Catchments would change by 0.7oC and 0.8oC; 1.3oC and 1.9oC; 1.7oC and 3.3oC; while Tmin would change by 0.9oC and 1.0oC; 1.6oC and 2.1oC; and 2.0oC and 3.8oC – for RCP4.5 and RCP8.5 in the early, mid and end-centuries, respectively. Increase in temperature would be higher in the cooler and wetter months and seasons (MAM, JJA) than in the warmer season (DJF) – which shows a temporal variation in change. While rainfall in the Catchments is projected to increase by 10% and 8%; 15% and 16%; and 20% and 30% – for RCP4.5 and RCP8.5 in the early, mid and end-centuries, respectively, the increase would be higher in the drier periods than in the wetter ones. Increase of rainfall alongside increase in temperature could result in increased evaporation to precipitation ratio over the coming years. This in turn creates a likelihood of an increased deficit in soil water and surface water flows. Therefore, crop and livestock producers would have to cope with moisture/water deficits through climate smart (soil) water management practices and crop and animal science. Key words: Climate scenarios, global warning, North-Eastern Uganda, water management