Samuel Agele, Ayodeji Bolarinwa
Climate change or climate variability has been predicted to have significant impacts on global and regional productivity of agricultural crops, food and nutrition security and livelihoods. In Sub Saharan Africa in particular, the performance of agricultural crops is predicted as highly susceptible to variabilities in climate and weather. The records of crop yields in Nigeria from 1961-2013 and some climatic variables (rainfall and temperature) were obtained while trends were analysed, and correlation and regression relations between yields and climate parameters conducted. The trends of changes in the yield per land area (hectare), area harvested and total yearly production was determined to accertain year to year variations for the period of study. The crops were selected because they constitute priority staple food and cash commodities under the nation’s Agricultural Transformation Agenda (ATA) action plan. Crop yields and climate variables differed markedly from year to year, in particular, decadal trends in temperature and rainfall varied widely across the period of study. Between 1962 and 2013, the yield per land area (hectare), area harvested and total yearly production had increased while yield per land area had not. There had been tremendous increases in the area harvested and total yearly production for pulses (cowpea and soybean), cereals (maize, rice and sorghum) and roots and tubers (cassava and yam). The results showed that the periods when the lowest and highest yields were obtained differed among species selected for study. The highest (43.50 kg/ha) and lowest (1.085kg/ha) yields for cassava were observed in 1999 and 2001, respectively, while both highest and lowest yields for sorghum were recorded in 2012.The yield change may be attributed to changes in climate and weather patterns while the coefficients of the regression models may help crop yield change forecasting. Crop productivity was particularly vulnerable to climate change and that weather factors in particular, rainfall and temperature varaibilities have significant effects on the yield of the crops in Nigeria.