Understanding flood dynamics in the Indus River Basin: Lessons from the 2022 Pakistan deluge

The study focuses on the Indus River Basin and southern Pakistan, severely affected by flooding in 2022. This study assessed how land surface temperature, snow cover, soil moisture, and precipitation contributed to the deluge of 2022. This study mainly investigated MODIS-AIRS land surface temperature, MODIS snow cover (NDSI), SMAP soil moisture, and GPM IMERG precipitation accumulation. Furthermore, different flood visualization and mapping techniques were applied to delineate the flood extent map using Landsat 8–9, Sentinel-2 MSI, and Sentinel-1 SAR data. The region experienced some of the most anomalous climatic events in 2022, such as prolonged heatwaves as observed with higher-than-average land surface temperatures and subsequent rapid decline in snow cover extent during the spring, increased soil moisture followed by an abnormal amount of extreme monsoon precipitation in the summer. The upper subbasins experienced more than 8℃ in positive temperature anomaly, indicating a warmer climate in spring. Subsequently, the snow cover declined by more than 25 % in the upper subbasins. Further, higher surface soil moisture values (> 0.3 m 3 /m 3 ) were observed in the basin during the spring due to the rapid snow and ice melt. Furthermore, the basin received more than 200 mm of rainfall compared to the long-term average rainfall of about 98 mm, translating to about 300 % more rainfall than usual in July and August. The analysis helps understand the spatial and temporal variability within the basin and facilitates the understanding of factors and their intricate connections contributing to flooding. • Understand flood dynamics in the Indus River Basin through 2022 Pakistan Flooding. • Use satellite-based hydroclimatic data to identify potential drivers of flooding. • Warmer spring climate and decline in snow cover seen in the basin’s upper reaches. • Higher antecedent soil moisture was observed prior to the onset of the monsoon. • Extreme monsoon precipitation on already moist ground caused catastrophic flooding.