Rainfall variability on the southern slope of the Bambouto mountain (West-Cameroon) and impact on the crop cultivation calendar

Abstract

A study on rainfall variability and its impact on the cultural cycle was carried out on the southern slope of the Bambouto mountain by using a long term data bank collected from 1941 to 2013 in the area. Statistical tests, including Pettitt's test, were used for the analysis. The study revealed that despite the average high rainfall (annual average rainfall of Dschang, 1846 mm and Djuttitsa 1639 mm), some drought recently occurred. The cumulated total approach indicated that these stations are located in the same climatic region. Annual rainfall for the Dschang meteorological station showed two distinct periods namely: a period of moisture excess from 1941 to 1976, and a period of moisture deficit from 1977 to 2013. The drought experienced in 1977 was characterised by a decrease in annual and monthly rainfall as well as the number of rainy days. This decrease, however, was not uniform in the year and from one year to another. There were also changes in the seasonal occurrence. Daily rainfall frequency analyses indicated that the growing season covers the period between 14 March and 12 November in Dschang, and between 22 March and 11 November in Djuttitsa. The appropriate planting date for the first season would be around 15 March in Dschang and 23 March in Djuttitsa.