Climate Variability and Agricultural Production: The Role of Temperature and Rainfall

Abstract

A time-series analysis approach was used in this study to explore the relationship between climate variability and agricultural production. Annual and seasonal temperature, rainfall and crop production data were taken for a selected agricultural area over an adequate time period, crop production data was derived from official agricultural statistics and temperature and rainfall data from meteorological observations. The data was compiled by major crop growing seasons and by this means the effects of the climatic conditions at the critical stages of crop development were taken into account. Trend analysis was initially carried out to assess temporal variation in temperature, rainfall and agricultural production, and then correlation analysis was conducted to assess the strength and direction of climate–agricultural production associations. Multiple regression analysis was then used to estimate the effect of temperature and rainfall variability on crop yield, while accounting for other production-related factors, with time-series diagnostic tests used to check the stationarity and autocorrelation of the data. The findings indicated statistically significant warming trends in both maximum and minimum temperature and decreasing trends in the amount of rainfall during the growing season were also significantly related to crop yield over the period of study. The regression results showed that an increase in temperature was accompanied by a decrease in yield, whereas an increase in growing-season rainfall and cultivated area was accompanied by an increase in yield; and the diagnostic tests showed that the estimated relationships were statistically valid (not affected by non-stationarity or autocorrelation). The study finds that seasonal climate variability is measurably influencing agricultural production in the study area and suggests the incorporation of seasonal climate forecasting and adaptation to rainfall variability in agricultural planning.