Abadi Berhane
Climate change is a real natural phenomenon. It is affecting agricultural productivity, especially in rain-fed agriculture. This paper provides comprehensive review studies on the impacts of climate change on crop and water productivity, soil water balance and food security. Global total annual anthropogenic GHG emission was grown by 70% between 1970 and 2004. The IPCC developed four emission scenarios or storylines, A1, A2, B1 and B2 and three groups of family storylines of A1FI, A1T and A1B. Climate predictions indicate a warmer world within the next 50 years, maximum and minimum temperatures increasing causing substantial yield decrease in low latitude areas; whereas, projected rainfall has no distinct variability pattern. By 2080, arid and semi-arid lands in Africa will increase by 5% to 8%. Global Climate Change Models (GCMs) have been used for different climate change impact assessment; however, due to lack of accuracy at local or smaller spatial simulation capacity; regional climate modeling, are being used to downscale climate scenarios at local and smaller scale around the world. Therefore, identifying and assessing suitable adaptation and mitigation practices have paramount importance and contributions to improve crop productivity, reduce the negative impacts of climate change on water availability and productivity. Global and regional climate models have been used as decision support tools for climate change impact assessment, and hence, application of such models to generate present and future climate data outputs for crop modeling and climate change impact assessment on crop production, water balance and food security is very essential.