Trends of winter precipitation extremes over Northwest Himalaya

Abstract

The intensity and frequency of extreme precipitation events are of great concern for water resources over the Indian Himalayas, where climate change is rapidly progressive. The long-term trends of extreme precipitation events have been examined during the winter season (November to April; 1996–2016) using the data of 10 observatories maintained by the Snow and Avalanche Study Establishment (SASE) over the Northwest Himalaya (NWH) region. The extreme events are categorized into seven indices, which are 90th and 95th percentiles, rainy days, and maximum 1-d, 3-d, 5-d and total accumulated precipitation. The analysis shows increasing trends for all seven indices for the peak month of February for all Himalayan ranges and altitudes. The rainy days are significantly increased at a 95% confidence level in the Pir-Panjal Range. The teleconnection study reveals that the negative correlation between the North Atlantic Oscillation and winter precipitation extremes is critical for the inter-monthly precipitation behaviours over the NWH. © 2021 IAHS.