Trend Of Rainfall In Abeokuta, Ogun State,Nigeria: A 2-Year Experience (2006-2007)
Keywords:
rainfall, Mann-Kendall, t-test, season, trendAbstract
Rainfall influences a lot of human activities like farming, sports and open air campaigns. It also influences environmental factors like level of water bodies and erosion. A 2-year rainfall data of Abeokuta between 2006 - 2007 was analysed using various statistical applications like the Mann-Kendall non-parametric test and the parametric student t-test for two separate time series of monthly total rainfall and rainy days. The result revvealed that the pattern of rainfall rises to a peak before falling to the 'August break', and rises to a mini peak before falling again into extinction. The results also showed an increasing trend from both the non-parametric and parametric tests with a rate of increase of 3.21mm/month using the total amount of rainfall time series, aside showing the seasonality of the location which possibly would not have been revealed if yearly data of large size were considered.
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