A Comprehensive Approach to Assess the Hydrological Drought of Inland River Basin in Northwest China

Abstract

How to measure and quantitatively assess hydrological drought (HD) in the inland river basins of Northwest China is a difficult problem because of the complicated geographical environment and climatic processes. To address this problem, we conducted a comprehensive approach and selected the Aksu River Basin (ARB) as a typical inland river basin to quantitatively assess the hydrological drought based on the observed data and reanalysis data during the period of 1980–2010. We used two mutual complementing indicators, i.e., the standardized runoff index (SRI) and standardized terrestrial water storage index (SWSI), to quantitatively measure the spatio-temporal pattern of HD, where the SRI calculated from the observed runoff data indicate the time trend of HD of the whole basin, while SWSI extracted from the reanalysis data indicate the spatial pattern of HD. We also used the auto-regressive distribution lag model (ARDL) to show the autocorrelation of HD and its dependence on precipitation, potential evapotranspiration (PET), and soil moisture. The main conclusions are as follows: (a) the western and eastern regions of the ARB were prone to drought, whereas the frequency of drought in the middle of the ARB is relatively lower; (b) HD presents significant autocorrelation with two months’ lag, and soil moisture is correlated with SWSI with two months’ lag, whereas PET and precipitation are correlated with SWSI with 1 month’ lag; (c) the thresholds of HD for annual PET, annual precipitation, and annual average soil moisture are greater than 844.05 mm, less than 134.52 mm, and less than 411.07 kg/m2, respectively. A drought early warning system that is based on the thresholds was designed.

Spatiotemporal Response of Hydrological Drought to Meteorological Drought on Multi-Time Scales Concerning Endorheic Basin

“…Ma et al [10] distinguished the lag time of hydrological drought in relation to meteorological drought through the correlation between the two and separated the contribution rate of human activities and climate change, according to the lag time. Likewise, scholars have administered various studies on the response of the hydrological drought to the meteorological drought at the Tarim River Basin [17][18][19]. However, due to the deficiency of meteorological and hydrological data regarding the Tarim River Basin, scholars have mostly targeted the temporal response of hydrological drought to meteorological drought without determining the spatial response.…”

Downscaling Precipitation in the Data-Scarce Inland River Basin of Northwest China Based on Earth System Data Products

“…The variations of precipitation and its impacts on ecosystems have gradually become crucial issues in hydrology and ecology, especially in Northwest China [5]. The ecosystems based on the supply of precipitation and meltwater in the arid regions of Northwest China are more vulnerable under global warming [6][7][8]. Northwest China is rich in natural resources with an extremely vulnerable ecological environment due to its limited water resources [6,7].…”

“…The ecosystems based on the supply of precipitation and meltwater in the arid regions of Northwest China are more vulnerable under global warming [6][7][8]. Northwest China is rich in natural resources with an extremely vulnerable ecological environment due to its limited water resources [6,7]. Under the background of global warming, the climate change in Northwest China has presented a warm-wet trend during the past decades [4,6,9].…”

Spatiotemporal Change of Plum Rains in the Yangtze River Delta and Its Relation with EASM, ENSO, and PDO During the Period of 1960–2012

“…When facing global climate change and frequent extreme climate events [36], how to understand the particularity and generality of the local Plum Rains and the relationship between the Plum Rains and atmospheric circulation on different time scales is an important scientific issue. For the above reasons, we select Shanghai, the Jiangsu province, and the Zhejiang province as a typical region.…”