Research Projects

The proposed study seeks to improve the understanding of atmospheric moisture dynamics in the Upper Ganga Basin (UGB), a hydrologically and climatologically sensitive region of the central Himalayas. While most existing hydrological research in this area focuses on surface or subsurface components such as river discharge or groundwater, this project uniquely targets the atmospheric phase—specifically, the origin, trajectory, and transformation of moisture prior to precipitation. Precipitation in the UGB is largely governed by two major synoptic systems: the Indian Summer Monsoon (ISM) and Western Disturbances (WDs). These systems differ in terms of source regions, seasonal timing, and isotopic signatures. However, their contributions are further complicated by local hydrological processes such as evapotranspiration and soil moisture feedbacks. This study hypothesizes that the precipitation in this region is not solely a result of long-range moisture transport but is significantly modified by local moisture recycling. To investigate this, the project will involve high-resolution sampling of both atmospheric vapour and rainfall across an elevation transect from Roorkee to Uttarkashi. Stable isotope analysis (δ¹⁸O, δ²H, and d-excess) will be performed to trace moisture sources and quantify contributions. Coupled with HYSPLIT back-trajectory modeling and meteorological data, the study will identify the spatial and seasonal patterns of moisture sources—both remote and local. This integrated approach will help delineate the dynamic interaction between atmospheric circulation and land surface processes. The study will fill a critical knowledge gap in understanding the pre-precipitation phase of the hydrological cycle in the UGB. It will also provide valuable insights into how climate change and land-use changes may affect rainfall distribution, moisture recycling, and water security in the Himalayan region. The findings are expected to influence climate modeling, monsoon prediction, and ecosystem-based water resource management strategies.

Stable Isotopes, Atmospheric Moisture, Indian Summer Monsoon, Western Disturbances, Moisture Recycling, Upper Ganga Basin