Changing trends of climate in Gilgit-Baltistan (GB) from 1955 to 2018

Abstract

This research aims to evaluate the long-term changing trends of climate over Gilgit-Baltistan (GB) from 1955 to 2018, over 64 years of observation data from six major stations in GB. For this purpose, Mann-Kendall and Sen’s Slope Estimator tests were employed to examine the seasonal and annual trends in key climatic parameters, temperature, and precipitation. Results signify an overall increasing trend in annual temperature at most stations, with statistically significant warming trends at Skardu and Astore at the same rate of 0.02 ^oC/year; Bunji showed a significant declining trend. Seasonal analysis revealed a consistent rise in winter temperatures at most stations, while summer temperatures declined, except at Astore, where slight increasing trend (0.01 ^oC/year) was detected.

Precipitation trends revealed spatial variability, with a significant increasing trend in Gupis, mostly during Spring, Summer, and Winter, with the highest increasing rate of 1.24 mm/year. Whereas Astore and Chilas stations showed non-significant decreasing trends in annual precipitation, -0.80 mm/year and -0.13 mm/year, respectively. The findings of this research revealed a shifting climatic regime in GB, characterized by increased seasonal precipitation and warmer winters, which has prime implications for glacier mass balance and downstream water flow. These findings specify critical scientific evidence for climate adaptation strategies and water resource management planning in the Upper Indus Basin (UIB).