Recent Changes in the Temperature and Rainfall Conditions Over Kaduna State, Nigeria
This study examines the evidence of climate change in Kaduna State, Nigeria, from the analysis of temperature and rainfall data (1971-2016) of three meteorological stations along a geographic transect in the State. Linear regression, second order polynomial, standard deviation and Cramer’s test were used to determine the changes in both the temperature and rainfall series. The result of the linear trend lines and second order polynomial revealed an increasing trend of temperature in recent years. The linear trend line revealed a mean increase in average temperature of 1.03oC for the State. The plotted standard deviation for the temperature anomalies generally showed that years of temperatures above the mean standard deviation in the last 16 years (2001-2016) were more than those below it. The Cramer’s test generally revealed an increasing temperature trend in the last two decades. The linear trend line of the annual rainfall revealed a mean increase of 303.32 mm for the State. Findings also revealed that the second order
polynomial generally showed a decreasing trend from 1971 to the late 1990s and an increasing trend afterwards up to 2016. The plotted standard deviation showed an increase in rainfall in recent years. The decadal analysis of rainfall in all the stations generally showed an increasing trend in the last two decades. The study recommends that awareness programs on recent changes in temperature and rainfall should be enhanced; greenhouse gases emission in the atmosphere
that have warming effect should be reduced; and, government policies related to agriculture, water resources, and other related sectors should take into account the increasing nature of temperature and rainfall amount in recent years.