Assessment of Satellite Precipitation Datasets Over Nepal and Its Application in Landslide Study: 

Present study evaluated IMERG V06 and V07 against Department of Hydrology and Meteorology (DHM) gauges data across Nepal’s complex topographis zones and additional point validation at Amrit Science Campus in Kathmandu. We further integrated IMERG rainfall with AMSR2 soil moisture to identify hydro-meteorological thresholds preceding nine rain-induced landslides. Results show that IMERG V07 consistently outperformed V06, reducing biases from as large as ±13 mm in the Himalayas and ±12 mm in the Mid-Hills to within about ±3 mm, and improving event detection rates with probabilities of detection of ~0.92–0.99 across all zones. Improvements were strongest in the Mid-Hills, the most landslide-prone belt. Validation at ASCOL further confirmed IMERG’s reliability during the monsoon. Landslide analyses revealed that failures were consistently preceded by extreme cumulative rainfall (often >100 mm within 1–3 days) and soil moisture levels approaching saturation (≥95–99%), underscoring their combined role as critical precursors. By demonstrating the enhanced accuracy of IMERG V07 and the value of integrating rainfall with soil moisture thresholds, this study strengthens early warning systems in Nepal.