Rainfall Seasonality and Standardized Precipitation Valuation of Water Resources Susceptibility to Climate Variability on the Bui Plateau, Northwest Region, Cameroon

This paper aims to assess the effects of climate variability on water resources, using Rainfall Seasonality Index (SI) and Standardized Precipitation Index (SPI). Water resources are subjected to hydro-climatic and spatial-temporal variations. They are a key constraint to economic development. Rainfall data collected were based on ground observations for stations across Bui. Water output data was also collected for a limited period from CAMWATER Jakri and Kumbo Water Authority. SI and SPI are computed using mean monthly and mean annual rainfall. The average Rainfall Seasonality Index stands at 0.915. This value falls within the class limit of 0.80–0.99. Thus, rainfall in is markedly seasonal with a long drier season. Normally, one would expect the index to be seasonal (0.60-0.79). The markedly seasonal rainfall with a long drier season is as a result of meteorological droughts that lead to a delay in the onset of first rains. standardized Precipitation Index on the other hand is a tool which was developed primarily for defining and monitoring drought. Indices for Bui range from -0.1 to -0.45 (mild to moderate drought conditions). The outcome of these extreme conditions has led to severe water shortages, especially during the dry season. Thus, there is need to enhance existing water resources and protect watersheds to ensure sustainability.

Keywords:Climate variability; Coping strategy; Precipitation; Vulnerability; Water scarcity