Paper Details

This study is an attempt to investigate the variabilities in the dry season rainstorm characteristics in Ibadan. Daily rainstorms data, particularly rainstorm events, duration and rainfall amount recorded in Ibadan during dry season between 1952 and 1982 were collected. Data collected were aggregated on monthly, annual and seasonal bases. Data were analyzed using descriptive statistics, paired sample t-test, and correlation analysis, at p≤0.05. The results among others showed that 295 rainstorms were recorded during dry season, with an average duration of 1 hour and close to 95% lasted less than two hours. The rains that accompanied the dry season rainstorms in Ibadan varied a great deal. Rainfall decreases from 125.8 mm (1976) to 12.8 mm (1982). About 9.7% of rainstorms gave less than 30 mm of rainfall; 74.2% yielded rainfall amounts of between 31.0 and 90.0 mm. Over 12% of the rainfalls were between 91.0 mm and 120 mm. Only about 3.2% of the rainfall was greater than 120 mm during dry season rainstorm events. There was significant difference between mean duration and rainfall amount (p=0.000). There was a relationship between rainstorm characteristics. In fact, the correlation coefficient produced between the rainstorm events, duration and rainfall amount showed that, duration ( .041) and rainfall amount (-.557) relatedinversely with the incidence of rainstorms. The correlation statistics further revealed that there was significant correlation between the duration and rainfall amount (.027).The results could serve as the backbone for urban, agricultural and disaster planning, all of which help to sustain man’s livelihood. Keywords: Daily Rainfall, Dry Season, Rainstorm Characteristics, Rainstorm duration, Rainfall Amount, Ibadan.