The 2021 Cyclone Seroja was a category 3 storm that made landfall on Lembata Island, causing extensive damage. This study aims to identify key interpretations of sediment transport related to tropical cyclones (TC) Seroja and past floods using a geopedological approach, estimate the return period through frequency analysis, and determine the rainfall threshold for flooding using HEC-RAS software. Extreme rainfall data from global precipitation model (GPM) (2000-2023) in Wei Laing watershed were analysed alongside LiDAR terrain data, physical and chemical properties of soil, and land cover data. Based on geopedological analysis, the result shows that the erosional-transfer zone of Wei Laing Watershed has thin, loamy, and slightly sandy soils due to erosion and limited pedogenesis. The depositional zone contains flood deposits with abrupt vertical texture changes, reflecting transported coarse grains and finer in-situ sediments. The modern flood deposit (TC Seroja flood deposit) was identified by texture, CaCO3 content, organic matter, and coarse organic material. The fine-grained flood deposits (<_ 4 cm) are classified as slackwater deposits, consist of silty clay loam and silt loam textures, reflecting deposition under slow-flowing conditions. TC Seroja corresponds to a 50-year return period. Hydrological modelling indicates a 60 mm/day rainfall threshold for flooding, with 77 flood events recorded between 2000-2023. The model is confirmed by thick past flood deposits enriched with coarse organic materials. These findings provide insight into flood dynamics and sedimentary responses, supporting future flood risk mitigation efforts.

Recent research on the Himalayan cryosphere has increasingly been focused on climate uncertainty and regional variations, considering features such as glacier recession, lake expansion, outburst floods, and regional hazards. The Bhilangana river basin, located in the central Himalayas, is predominantly characterized by increased elevation-dependent warming and declining seasonal precipitation. Our study shows that high-elevation temperature increased from 2000 to 2022 (0.05(degrees)C/year, p = 20 m/sec). Quantification of the regional hazard reveals potentially severe downstream challenges for low-to-medium-scale hydropower stations, local settlements, and road and railway bridges near Devling and Ghuttu villages.

Due to recent rainfall extremes and tropical cyclones that form over the Bay of Bengal during the pre- and post-monsoon seasons, the Nagavali and Vamsadhara basins in India experience frequent floods, causing significant loss of human life and damage to agricultural lands and infrastructure. This study provides an integrated hydrologic and hydraulic modeling system that is based on the Soil and Water Assessment Tool model and the 2-Dimensional Hydrological Engineering Centre-River Analysis System, which simulates floods using Global Forecasting System rainfall forecasts with a 48-h lead time. The integrated model was used to simulate the streamflow, flood area extent, and depth for the historical flood events (i.e., 1991-2018) with peak discharges of 1200 m3/s in the Nagavali basin and 1360 m3/s in the Vamsadhara basin. The integrated model predicted flood inundation depths that were in good agreement with observed inundation depths provided by the Central Water Commission. The inundation maps generated by the integrated modeling system with a 48-h lead time for tropical cyclone Titli demonstrated an accuracy of more than 75%. The insights gained from this study will help the public and government agencies make better decisions and deal with floods.