ANALYSIS OF LONG-TERM METEOROLOGICAL TRENDS OVER NIGERIA-A NON-PARAMETRIC STATISTICAL APPROACH

Abstract

Nigeria, the study area, is subject to climatic variation which has a direct effect on the agricultural sector, transportation sector, telecommunication, as well as the livelihoods of the poor people who are highly dependent on agriculture. The situation, however, has been on an increase in majority of the climatic zones in Nigeria. The objective of this research is to analyse the long term meteorological trend collected by 20 weather stations spread across Nigeria. Monthly data from 1970 to 2010, and the non-parametric seasonal Mann Kendall test for the trend detection in combination with the Sen’s slope estimator were used to measure the extent of these trends. The maximum temperature, minimum temperature and rainfall are the meteorological parameters being examined. Majority of the locations exhibited an increasing trend for maximum and minimum temperature with rainfall. The Sen’s slope estimate Q that all the stations have has a positive magnitude with the order of 10^-2 which indicates an increasing trend in temperature. Results reveal that the air temperature is on an increasing trend per decade likewise the rainfall amount. Overall, the study area is under a significant warming trend with little or majorly non-significant changes in rainfall.