Recent Wintertime Climatic Variability over the North West Himalayan Cryosphere

This study discusses the observed long-term (1991–2015) and short-term (1991–2000 and 2001–2015) trends in winter temperature and precipitation over Northwestern Himalaya (NWH) along with its constituents, i.e. Lower Himalaya (LH), Greater Himalaya (GH) and Karakoram Himalaya (KH). An overall warming signature was observed over NWH since maximum, minimum and mean temperatures followed rising trends with a total increase of 0.9°C, 0.19°C and 0.65°C respectively, in 25 years, the increase being statistically significant for maximum and mean temperatures. However, warming was not consistent over all zones of NWH with minimum temperature at LH showing anomalous cooling by 0.83°C (statistically significant at α = 0.05) during 25 years. The rise in mean temperature was observed highest at GH, i.e. 0.87°C (1991–2015) followed by KH, i.e. 0.56°C, which is in agreement with observations of comparatively higher rate of glacier retreat over GH than KH as reported in several studies. Total precipitation (rainfall + snowfall) was found to increase whereas snowfall was found to decrease with concurrent significant increase in rainfall at all zones of NWH. The spatiotemporal winter climatic variations over NWH support the impact on recently reported findings on the Himalayan snow cover and glacier variations at different durations.