Abstract:
Observed rainfall data (1961–2016) were used to analyze variability, trends and changes
of extreme precipitation indices over Benin. Nine indices out of the ones developed by the Expert
Team on Climate Change Detection and Indices (ETCCDI) were used. The results indicate a mix of
downward and upward trends for maximum 1-day precipitation (RX1day) and maximum 5-days
precipitation (RX5day). Decrease trends are observed for annual total precipitation of wet days
(P), while significant increases are found for the simple daily intensity index (SDII). The number of
wet days (RR1) and maximum consecutive dry days (CDD) show a mix of increase/decrease trends.
However, the number of heavy (R10) and very heavy (R20) wet days and maximum consecutive
wet days (CWD) show decreased trends. All wet indices increased over 1991–2010 in relation to
1971–1990. The increase in all wet indices over Benin could explain the intensification of hydrology,
and the increase in the frequency and the intensity of floods. It caused damages such as soil erosion,
crop destruction, livestock destruction, displacement of populations, proliferation of waterborne
diseases and loss of human life. Some adaptive strategies are suggested to mitigate the impacts of
changes in extreme rainfall.
