Variation of Rainfall and Humidity in Nigeria

Abstract

Thirty-one year (1979-2010) annual rainfall and relative humidity for eight stations scattered over Nigeria have been analysed. Rainfall is highly variable in both time and space, particularly in sub-humid tropical regions like West-Africa. The analysis was done using statistical package. The mean, standard deviation and coefficient of variation for both relative humidity and rainfall for the study area were calculated. The results shows that the range of the standard deviation  for relative humidity for the study areas lie between7.0 and10.5 while its range of the coefficient of variation is between 0.02 and0.35.Coefficient of variation for the rainfall for the period of study is between 0.25and5.65, increasing  from the coastal areas into the hinterland. The monthly  analysis also show that period of highest rainfall falls between June or July and August or September for the locations nearest to the coast and those closer to the Sahara desert respectively. The trend of the rainfall in Nigeria within the study period is 0 .654per annum.

Keywords: Trend, rainfall, humidity analysis, coefficient of variation, distributional pattern