Trends and variability of extreme climate indices in the Boucle du Mouhoun (Burkina Faso)

The main objective of this study is to analyse the trends and variability of extreme weather indices in the Boucle du Mouhoun region of Burkina Faso. To this end, meteorological data for the period 1991 to 2021 were obtained from the National Meteorological Agency of Burkina Faso. These meteorological data (rainfall, temperature) were integrated into the Rclimdex software to generate extreme climate indices (rainfall, temperature). These data were then analysed by means of homogeneity tests (Pettitt and von Neumann ratio), trend tests (Mann-Kendall, Sen's slope) and the frequency of the return period of the extreme climate indices using XLSTAT (Statistical Software for Excel) 2023. The study shows that the precipitation indices are overall homogeneous (p-value ≥ 0.05) and that there is no significance (p-value ≥ 0.05) for the trend of the extreme precipitation indices from 1991 to 2021. Conversely, the temperature indices are not homogeneous (p-value ≤ 0.05), and a significant upward trend was observed for the maximum temperature index (p-value ≤ 0.05) and the minimum temperature index (p-value ≤ 0.05). The extreme climate indices also show considerable variability over the period 1991-2021. Moreover, the return periods for the occurrence of extreme climate indices are shorter, ranging from 0 to 10 years. It is therefore important that regional authorities in the area develop strategies to consolidate water infrastructures and provide financial support to producers, especially banana producers.