Warming Trends and Changing Precipitation Extremes in the Eastern Greater Himalaya: A Spatio-Temporal Analysis (1981–2025)

Rainfall variability plays a significant role in modulating both aquatic and socioeconomic systems in the Eastern Himalayas. Among the longitudinal ranges of the Himalayas, the Greater Himalaya is considered the most vulnerable due to its high climatic sensitivity and steep topography. Given this importance, the present study investigates the spatial patterns of temperature and precipitation, their trends, and the occurrence of extreme events over Eastern Greater Himalaya (EGH) during 1981–2025. High-resolution gridded datasets for temperature (0.1° × 0.1°) from ERA5-Land and precipitation (0.05° × 0.05°) from CHIRPS are used. The significance and magnitude of trends are quantified using the Mann–Kendall test and Sen’s slope, respectively. The temperature in EGH is increasing at ~0.27 °C per decade, with the most pronounced increase during winter (>0.4–0.5 °C per decade). Temperature extremes show a clear shift toward warmer conditions, with an increasing frequency of warm days and nights (TX90p: ~0.29; TN90p: ~0.64), along with rising intensity (TXx: ~0.007 °C/year; TNn: ~0.04 °C/year) and a decline in cold extremes. Precipitation exhibits high spatial variability (<500 mm to >2000 mm) but weak and statistically not significant long-term trends. The monsoon contributes the highest precipitation (~1200–2000 mm), with a shift toward drier conditions after 2010–2015. Extreme precipitation indices show declining trends in daily maximum (RX1day: ~5–140 mm), maximum 5-day (RX5day: ~8.4–240 mm), total (PRCPTOT: ~−0.23 mm/year) and intensity of (SDII: ~−0.041 mm/day) precipitation. This research indicates a significant climate shift in EGH with rapid warming along with uncertain precipitation patterns, which may have implications for water resources, aquatic systems, and dependent communities.