Effect of Climate Variables on Yield of Major Food-Crops in Nepal: A Time-Series Analysis

Abstract

Therefore, this chapter assesses the effect of observed climate variables on yield of major food-crops in Nepal, namely rice, wheat, maize, millet, barley and potato based on a regression model for historical (1978–2008) climatic data and yield data for the food-crops. The yield growth rate of all the food-crops is positive. However, the growth rate for all crops, except potato and wheat, is below the population growth rate during the period. Climate variables like temperature and precipitation are the important determinants of crop yields. Trend of precipitation is neither increasing nor decreasing significantly during this period. However, the temperature is increasing by 0.7 °C during the period. Climate variables show some influences on the yield of these major food-crops in Nepal. Increase in the summer rain and maximum temperature has contributed positively to rice yield. Also, increase in the summer rain and minimum temperature has a positive impact on potato yield. However, increase in the summer rain and maximum temperature adversely affected the yield of maize and millet. Increase in wheat and barley yield is contributed by the current trend of winter rain and temperature. Consideration of spatial variation in similar type of study in Nepal that will be helpful in identifying the region more vulnerable to climate change in terms of crop yield is highly recommended.