The Impact of Climate Change on Rice Production in Nepal

This paper examines the sensitivity of rice yield in Nepal to changes in climate variables and the magnitude of potential impacts on rice productivity in the future. Our findings draw attention to the differential impacts on rice yield depending on which stage of rice development is affected. We estimate that a 1°C rise in day-time maximum temperature during the ripening phase of rice increases harvest by 27 kg. Ha-1, but our analyses also suggests that productivity declines when the daytime maximum temperature goes beyond 29.9°C. Since the average maximum temperature is already higher than this threshold, rice yield will likely diminish with any further increases in maximum temperature. Rainfall appears to have a strong negative effect on yield if it occurs when rice plants are in the nursery stage. Overall, under a double CO2 scenario predicted for 2100, rice yield in Nepal is expected to drop by about 4.2 per cent relative to current production levels. However, this prediction is does not account for any long-term positive effects from adaptation and carbon fertilization or negative effects from extreme events triggered by climate change.