ANNOUNCEMENTS
Climate change is intensifying water challenges in the Eastern Himalayas, impacting glaciers and snow melt. Bridging climate change and water demand understanding is vital, especially in India's ungauged Himalayan catchments. Limited hydrological data complicates assessments, and proposed novel methodologies aim to differentiate the changing climate and anthropogenic influences impacts on catchment hydrology. A spatiotemporal assessment of evaporative demand change using SWAT and Budyko models at the micro-watershed level, coupling climate and surface changes for local hydrology understanding is performed in this study.
Coupling climate and land-use models is crucial for comprehensive analysis, emphasising monitoring, and quantifying LULC changes' effects on water resources at the watershed scale over different years. The Budyko conceptual model, integrated with the SWAT model, enables the analysis of hydrological changes due to climate or human activities at the micro-watershed scale. The model considers climate parameters, obtained through SWAT, to differentiate the difference in two influences on water. The Budyko curve, depicting the relationship between precipitation, evapotranspiration, and runoff, aids in partitioning evaporative demand into green and blue components. Parameters like d-statistics, responsivity, and elasticity assess watershed sensitivity to land use and climate change.
The method unveiled novel catchment characteristic values within the range of 1.70 to 1.56 from 2005 to 2030, indicative of a discernible shift in hydrological patterns attributed to modifications in land cover and variables of climate. The alterations in precipitation, LULC, and temperature were identified as primary influencers on hydrological regimes, rendering watersheds increasingly susceptible to climatic variations. The investigation underscored the significant impact of LULC changes, manifesting as a reduction in snow and glacier cover alongside an augmentation in blue ET. Catchments exhibited low resilience to climate change, with six specific catchments in Arunachal Pradesh identified as particularly vulnerable. This emphasizes the exigency for targeted funding allocation, specifically through the National Mission on Climate Change, to safeguard the ecologically delicate Eastern Himalayan ecosystem.
