Assessment of Impacts of Climate Variability on Crop Yield over the Terai Region of Nepal

Abstract:

Agricultural sector in Nepal which alone contributes about 42 % of the total GDP have a huge influence on national economy. This sector is very much susceptible to climate change. This study is emphasized on Terai region (situated at an altitude of 60m to 300m) of Nepal which investigates the impacts of climate variability on various stages of cropping (paddy) periods such as transplant, maturity and harvest. The climate variables namely temperature and rainfall are used to explore the relationship between climate and paddy yields based on 30 years of historical observed data. Observed monthly rainfall and temperature data are collected from the department of hydrology and meteorology, and paddy yield data are collected from the Ministry of Agricultural Development. A correlation analysis will be carried out between the backward difference filtered climate parameters and the backward difference filtered rice yield. This study will also analyze average monthly and annual rainfall, and, min, max and mean temperature during the period of 1981-2010 based on 15 synoptic stations of Nepal. This study will visualize rainfall and temperature distribution over Nepal, and also evaluate the effect of change in rainfall and temperature in the paddy yield. While evaluating the impacts of climate on crop yield, this study will not consider the impact of irrigation in crop yield. The major results, climate distribution and its local/regional impacts on agriculture, could be utilized by planners, decision makers, and climate and agricultural scientists as a basis in formulating/implementing future plans, policies and projects.