Search

The June‐October 2020 growing season was characterized by sustained and extreme flooding across the African Sahel. One consequence of flooding events such as this is outbreaks of vector borne diseases (VBDs) which are often associated with climate anomalies. In this study, data from the soil moisture active passive (SMAP) mission is used with other soil moisture and precipitation data to show that the 2020 Sahelian growing season was the most extreme over the past four decades, ranking first in seasonally accumulated precipitation, which on average exceeded the climatology by around 300 mm. VBD outbreaks of Rift Valley fever and Chikungunya followed in Mauritania/Senegal and Chad, respectively. In some cases, soil moisture is a better indicator of VBD outbreak risk than precipitation, which has so far been more commonly used in studies of VBD outbreaks. It is expected that this finding will inform future monitoring and prediction efforts for VBD risk. Extreme rainfall and flooding can be harmful to society in many ways; this study examines the case study of flooding that affected the African Sahel during the summer of 2020. One consequence of flooding events is the increased risk of vector‐borne diseases outbreaks. These outbreaks are often linked with anomalies in climate variables such as precipitation, temperature, and vegetation conditions which prime disease vector habitats. This study uses satellite‐measured soil moisture information to assess the 2020 Sahel flooding and its relation to outbreaks of Rift Valley fever and Chikungunya vector‐borne disease outbreaks. It is shown that this event was very extreme in the context of the historical data record, and soil moisture is shown to be a valuable information source for indicating the potential risk areas of disease outbreaks. Above‐normal precipitation of up to 600 mm locally led to flooding in the African Sahel during the 2020 growing season (June‐October)Precipitation and surface soil moisture data indicate that this event was among the most extreme in the region in recent decadesThis event is linked with disease outbreaks, and soil moisture is potentially a better indicator of outbreak risk than precipitation alone Above‐normal precipitation of up to 600 mm locally led to flooding in the African Sahel during the 2020 growing season (June‐October) Precipitation and surface soil moisture data indicate that this event was among the most extreme in the region in recent decades This event is linked with disease outbreaks, and soil moisture is potentially a better indicator of outbreak risk than precipitation alone