Rainfall regime across the Sahel band in the Gourma region, Mali

The Sahel is characterized by low and highly variable rainfall, which strongly affects the hydrology and the climate of the region and creates severe constraints for agriculture and water management. This study provides the first characterization of the rainfall regime for the Gourma region located in Mali, Central Sahel (14.5–17.5°N and 2–1°S). The rainfall regime is described using two datasets: the daily long term raingauge records covering the period 1950–2007, and the high frequency raingauge records collected under the African Monsoon Multidisciplinary Analysis (AMMA) project between 2005 and 2008. The first rainfall dataset was used to analyse the interannual variability and the spatial distribution of the precipitation. The second dataset is used to analyse the diurnal cycle of precipitation and the nature of the rainfall. This study is complementary to previous analyses conducted in Sahelian areas located further south, where the influence of the continental Sahara heat low is expected to be less pronounced in summer.