Publications

Thapa, S; Pokhrel, R; Banjara, B; Nyaupane, B; Dhakal, A (2025). Seasonal and topographical dynamics of precipitable water vapor in Nepal: A GNSS-based assessment. DYNAMICS OF ATMOSPHERES AND OCEANS, 110, 101548.

Abstract
Precipitable water vapor (PWV), a key indicator of atmospheric moisture, plays a vital role in weather forecasting, climate studies, and understanding atmospheric thermodynamics. This study utilizes ground-based GNSS technology to estimate PWV and Zenith Tropospheric Delay (ZTD) across three distinct topographical regions of Nepal: Terai, Hilly, and Himalayan, over four seasons: winter, spring, summer, and autumn. The analysis reveals that the Terai region, characterized by lower elevations, consistently exhibits higher PWV and ZTD values compared to the high-altitude Himalayan region, with the Hilly region showing intermediate levels. Seasonal variations indicate the highest PWV and ZTD during the summer and the lowest during winter, reflecting the influence of monsoonal moisture. Diurnal variability analysis further shows significant fluctuations in PWV, with a minimum in the early morning (21:45-00:45 UTC) and at night (17:15-18:15 UTC) and a maximum during the warmest part of the day (6:15-9:15 UTC). These findings underscore the effectiveness of GNSS technology in monitoring atmospheric water vapor and highlight the significant impact of topography and seasonal cycles on PWV distribution in Nepal. Such research and insights are crucial for improving weather forecasting, advancing climate change research, and enhancing atmospheric monitoring in regions with diverse topographical features.

DOI:
10.1016/j.dynatmoce.2025.101548

ISSN:
1872-6879