Impact of climate change on crop water requirements and adaptation strategies Challenges and opportunities in Agrometeorology

Abstract

Water is an important for all forms of life and it is becoming scarce natural resource in the future owing to climate variability / change which aggravates the situation. Water resources are inextricably linked with climate. Climate change and variability would be the principal source of fluctuation in global food production, particularly in the semi-arid tropical countries of the developing world. In conjunction with other physical, social and political-economic factors, climate variability contributes to vulnerability to economic loss, hunger, famine and dislocation in the developing countries. Climate change impact studies reveal that annual average river runoff and water availability are projected to increase by 10-40% at high latitudes and in some wet tropical areas, and decrease by 10---30% over some dry regions at mid-latitudes and in the dry tropics. Crop water availability shortage and excess affects the growth and development of the plants, yields and quality of produces. Climate change, which affect the water availability resources, which in turn affect agriculture in many ways. For instance in soil plant processes with an increase in soil water deficit by changes in soil water balance. Long term climate change and its effect on crop water requirements of major cereal crops like wheat, maize, sorghum and millet in 1990,2020 and 2050 were estimated by FAO CROPW AT program and the adaptation strategies to be taken to combat climate change effect were also discussed in this paper.