Unraveling the Hydrology of the Glacierized Kaidu Basin by Integrating Multisource Data in the Tianshan Mountains, Northwestern China

Abstract

Understanding the water balance, especially as it relates to the distribution of runoff components, is crucial for water resource management and coping with the impacts of climate change. However, hydrological processes are poorly known in mountainous regions due to data scarcity and the complex dynamics of snow and glaciers. This study aims to provide a quantitative comparison of gridded precipitation products in the Tianshan Mountains, located in Central Asia and in order to further understand the mountain hydrology and distribution of runoff components in the glacierized Kaidu Basin. We found that gridded precipitation products are affected by inconsistent biases based on a spatiotemporal comparison with the nearest weather stations and should be evaluated with caution before using them as boundary conditions in hydrological modeling. Although uncertainties remain in this data‐scarce basin, driven by field survey data and bias‐corrected gridded data sets (ERA‐Interim and APHRODITE), the water balance and distribution of runoff components can be plausibly quantified based on the distributed hydrological model (J2000). We further examined parameter sensitivity and uncertainty with respect to both simulated streamflow and different runoff components based on an ensemble of simulations. This study demonstrated the possibility of integrating gridded products in hydrological modeling. The methodology used can be important for model applications and design in other data‐scarce mountainous regions. The model‐based simulation quantified the water balance and how the water resources are partitioned throughout the year in Tianshan Mountain basins, although the uncertainties present in this study result in important limitations.

Changes in Snow Phenology from 1979 to 2016 over the Tianshan Mountains, Central Asia

“…Previous studies indicated that the TS have experienced a significant warming trend over the past few decades [44][45][46]. The snowfall/precipitation ratio showed a decreasing trend accompanied by increasing temperatures in the TS [47], which intensified glacier and snow melt [2], leading to increasing runoff and earlier peak runoff from glacier/snow melt in these recharging river basins [45,[48][49][50]. Several studies have investigated the impact of glacier change on water resources in the TS [42,51-53], but only a few studies have addressed the snow cover changes with optical remote sensing [54,55].…”

Evaluation of the CRU TS3.1, APHRODITE_V1101, and CFSR Datasets in Assessing Water Balance Components in the Upper Vakhsh River Basin in Central Asia

“…These findings are in agreement with the results of a study by Shen et al in the Kaidu Basin in Central Asia. Shen et al [37] used gridded products, including CFSR, APHRODITE, CRU, TRMM, ERA-Interim and MERRA-2, with the J2000 model to analyze the spatiotemporal patterns of water balance and the distribution of runoff components in the glacierized Kaidu Basin in Central Asia. The results showed that APHRODITE and CRU represented annual and seasonal precipitation dynamics that were similar to the observational dataset at most climate points [37].…”

“…Shen et al [37] used gridded products, including CFSR, APHRODITE, CRU, TRMM, ERA-Interim and MERRA-2, with the J2000 model to analyze the spatiotemporal patterns of water balance and the distribution of runoff components in the glacierized Kaidu Basin in Central Asia. The results showed that APHRODITE and CRU represented annual and seasonal precipitation dynamics that were similar to the observational dataset at most climate points [37]. Similarly, a water balance study with the application of the SWAT model and observational datasets was conducted in the Indian Ken River Basin in South Asia, from 1986 to 2005 [20].…”

Estimating the longevity of glaciers in the Xinjiang region of the Tian Shan through observations of glacier area change since the Little Ice Age using high-resolution imagery

“…The glacial meltwater in the upper Kaidu River basin directly affects the availability of water downstream seasonally for its potential uses, such as for human consumption, irrigation, industry, etc. Losses in glacier volume also influence the seasonal timing and variability of streamflow (Shen and others, 2018). These hydrological changes will influence future water management decisions in the region regarding intra- and inter-basin water transfers, irrigation and dam construction (Chipman and others, 2016).…”