Spatiotemporal Variability in the Hydrometeorological Time-Series over Upper Indus River Basin of Pakistan

Abstract

This paper investigates the spatiotemporal variability in hydrometeorological time-series to evaluate the current and future scenarios of water resources availability from upper Indus basin (UIB). Mann–Kendall and Sen’s slope estimator tests were used to analyze the variability in the temperature, precipitation, and streamflow time-series data at 27 meteorological stations and 34 hydrological stations for the period of 1963 to 2014. The time-series data of entire study period were divided into two equal subseries of 26 years each (1963–1988 and 1989–2014) to assess the overlapping aspect of climate change acceleration over UIB. The results showed a warming pattern at low altitude stations, while a cooling tendency was detected at high-altitude stations. An increase in streamflow was detected during winter and spring seasons at all hydrological stations, whereas the streamflow in summer and autumn seasons exhibited decreasing trends. The annual precipitation showed a significant decreasing trend at ten stations, while a significant increasing trend was observed at Kohat station during second subseries of the study period. The most significant winter drying trends were observed at Gupis, Chitral, Garidopatta, and Naran stations of magnitude of 47%, 13%, 25%, and 18%, respectively, during the second subseries. The annual runoff exhibited significant deceasing trends over Jhelum subbasin at Azad Pattan, Chinari, Domel Kohala, Muzaffarabad, and Palote, while within Indus basin at Chahan, Gurriala, Khairabad, Karora, and Kalam in the second time-series. It is believed that the results of this study will be helpful for the decision-makers to develop strategies for planning and development of future water resources projects.

Characterization of Interannual and Seasonal Variability of Hydro-Climatic Trends in the Upper Indus Basin

“…The change point analysis marked significant variation in streamflow for Bunji and Astore river. The finding of this study is also consistent with a recent study (Yaseen et al 2020).…”

Temperature Projections over the Indus River Basin of Pakistan Using Statistical Downscaling

“…Therefore, a low-warming MS in the UIB at the end of the 21st century is possible and may further extend into the high-altitude regions under the same MS forcing. Many earlier studies, e.g., [32,33,35,37] have shown MS cooling tendencies. Although our model-ensemble did not show MS cooling except over one region, some of the individual models projected some cooling.…”

“…Note that the humidity predictors dominate the PMS regression models (Table 4), and, therefore, future changes in atmospheric humidity will strongly influence the regional temperatures. Previous studies, e.g., [33,36,39], also projected PMS warming over the UIB through T max changes.…”

“…Moreover, a decreasing diurnal temperature range (DTR), e.g., [23] and a greater increase in maximum temperatures, e.g., [24][25][26] over the UIB are different patterns than the globally increasing DTR, e.g., [27,28], and prominent warming of minimum temperatures over adjacent China and Tibetan Plateau, e.g., [29,30]. Additionally, elevation-dependent warming (EDW) is well accepted globally, e.g., [7,31], but some recent studies have argued its relevance within the UIB, e.g., [32,33].…”

Climate change projections over Indus basin using CMIP6 model simulations

“…11). The studies of Yaseen et al (2020) reported a spatiotemporal variation in temperature trends over the UIB. As UIB consists of Shyok and Shigar, Astore and Haunza, Gilgit, Jehlum, and Kabul sub-basin as part of UIB, which have different elevations, regions with low altitude face the warming trend, and the areas with high altitude show the cooling trends.…”