A Holistic View of Water Management Impacts on Future Droughts: A Global Multimodel Analysis

Abstract

This study investigates the impacts of climate change and water management including agricultural irrigation, water withdrawal, and reservoir regulation on future meteorological, agricultural, and hydrological droughts and their connections. The analysis is based on the simulations from four global hydrological models forced with the projections from five global climate models for historical period 1971–2000 and future period 2070–2099 with and without water management. Three unified drought indices, the standardized precipitation index, standardized soil moisture index, and standardized streamflow index, are adopted to represent the meteorological, agricultural, and hydrological droughts, respectively. The analysis suggests that the climate‐induced drought changes in all three types of droughts are enhanced but in different directions, while water‐management‐induced changes in agricultural and hydrological droughts are more consistent across space and simulations. Overall, water management activities reduce both the duration and intensity of agricultural droughts by roughly 1 order of magnitude, while increase those of hydrological droughts by up to 50%. Basin‐scale analysis reveals that the higher is the intensity of irrigation, the larger will be the water‐management‐induced drought changes. Due to water management activities at some regions, the return periods of extreme agricultural droughts (in terms of severity) can change from 100 to 300 years or even longer, while typical 100‐year hydrological droughts are likely to occur more often for the regions located in 25°N–40°N and 15°S–50°S. This study provides a global view on drought modification in the Anthropocene, which will help improve adaptation strategies for future droughts.

Signatures of human intervention – or not? Downstream intensification of hydrological drought along a large Central Asian river: the individual roles of climate variability and land use change

“…This clearly underlines the argument by Haile et al (2019a), indicating that human activities such as expansion of cultivation and overexploitation of water resources, particularly for irrigation demands, have an impact on altering the hydrological processes which are directly linked to drought. Our results further illustrate that flow deficits and droughts in the HRB clearly reflect the dynamic interplay between temporally varying regional differences in hydro-meteorological variables together with subtle and temporally varying effects linked to direct human intervention (Jehanzaib et al, 2020;Jiang et al, 2019;Saidi et al, 2018;Wan et al, 2017).…”

“…Large reservoirs such as the Kajakai (ID9) and Dahla (ID10) Dam reservoirs in the HRB can considerably alter downstream flow regimes (Haddeland et al, 2014;Wada et al, 2016). This has recently received growing attention, and a number of studies have suggested methods to quantify reservoir outflow where reservoir operation rules are largely unknown (e.g., Coerver et al, 2018;Yassin et al, 2019).…”

“…In general, it is well understood that both agricultural and hydrological droughts are modulated by the interactions of climate and river basin characteristics, such as geology, as well as a human influence or any combination thereof (e.g., Van Lanen et al, 2013;Huang et al, 2016;Liu et al, 2016;Van Loon et al, 2019). For example, data show that reservoir operations can have both considerable positive and negative effects on downstream hydrological-drought pattern (e.g., Zhang et al, 2013;Piqué et al, 2016;Wu et al, 2017), which may politically be particularly sensitive for transboundary rivers in arid environments (Al-Faraj and Scholz, 2014;Wan et al, 2018).…”

Impact of Droughts on Water Supply in U.S. Watersheds: The Role of Renewable Surface and Groundwater Resources

“…Finally, the analysis in this study has been performed for the observed climate variability in the past and the impact of climate change is not assessed. Climate change is not only expected to intensify droughts in future (Wan et al, 2018; Zhai et al, 2020) but is also likely to contribute to changes in both the annual mean and seasonality of precipitation and evapotranspiration regimes in the future (Konapala et al, 2020), which can result in changes in regional drought propagation mechanisms. Therefore, future studies can investigate how the integrated use of surface and groundwater, as suggested in this study, can mitigate the effects of climate change.…”

Revisiting Water Supply Rule Curves with Hedging Theory for Climate Change Adaptation

“…Both climate change and human activities may aggregate hydrological non-stationarity [9,42]. The reservoir storage or outside characteristic may change due to sedimentation, population and economic growth, groundwater access, new hydraulic structure construction, climate-induced changes on catchment hydrology, etc.…”