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The Clausius‐Clapeyron relationship holds that the atmospheric water vapor content enhances with warming temperatures, suggesting intensifications of precipitable water and also altering runoff generation. Drought conditions are determined by variations in water fluxes such as precipitation and runoff, which tightly connect with temperature scaling characteristics. However, whether and how water fluxes' scaling with temperatures may affect the evolution of droughts under climate change has not yet been systematically investigated. This study develops a cascade modeling chain consisting of the climate model ensemble, bias correction technique, and hydrological models to investigate the precipitation and runoff scaling relationships with warming temperatures under the current (1961–2005) and future periods (2011–2055 and 2056–2100), as well as their implications on future drought changes across 151 catchments in China. The results show that (1) precipitation (runoff) scaling relationships with temperatures are stable during different time periods; (2) return level analysis indicates drought risks are projected to become (1–10 times) more severe across central and southern catchments, where the precipitation (runoff) strengthens with rising temperatures up to a peak point and then decline in a hotter environment. The northeastern and western catchments, where a monotonic increasing scaling type dominated, are accompanied by drought mitigations for two future periods; (3) future changes in hydrological droughts relative to the baseline are (1–5 times) larger than those in meteorological droughts. These results imply that changes in future drought risks are highly dependent on the present precipitation (runoff)‐temperature relationships, suggesting a meaningful implication of scaling types for future drought prediction. Plain Language Summary: Drought hazards are determined by variations in water fluxes such as precipitation and runoff. Global climate warming has altered these terrestrial hydrological processes and subsequently changed drought conditions. Characterizing the responses of precipitation and runoff to warming climates and investigating their implications on future drought changes are important for drought early warning and prediction. Here we show that monthly precipitation and runoff either exhibit a monotonic increasing or the peak‐like structure (in which precipitation and runoff increase with warming temperatures up to a peak point and decline thereafter) with temperatures. The increasing relationship typically suggests future drought mitigation, while the hook structure type, which prevails in central and southern catchments in China, implies increasing drought risks. Our findings facilitate a better understanding of drought changes under climate change and provide a scientific basis for drought adaptation to climate change. Key Points: Monthly precipitation and runoff typically exhibit a monotonic increasing or hook structure with temperature scaling in ChinaThe hook structures typically imply future intensifying drought hazards, whereas the increasing scaling types infer drought mitigationsFuture changes in hydrological droughts relative to the historical baseline are larger than those in meteorological droughts [ABSTRACT FROM AUTHOR]

Long‐range water planning is complicated by factors that are rapidly changing in the 21st century, including climate, population, and water use. Here, we analyze climate factors and drought projections for Texas as an example of a diverse society straddling an aridity gradient to examine how the projections can best serve water stakeholder needs. We find that climate models are robust in projecting drying of summer‐season soil moisture and decreasing reservoir supplies for both the eastern and western portions of Texas during the 21st century. Further, projections indicate drier conditions during the latter half of the 21st century than even the most arid centuries of the last 1,000 years that included megadroughts. To illustrate how accounting for drought nonstationarity may increase water resiliency, we consider generalized case studies involving four key stakeholder groups: agricultural producers, large surface water suppliers, small groundwater management districts, and regional water planning districts. We also examine an example of customized climate information being used as input to long‐range water planning. We find that while stakeholders value the quantitative capability of climate model outputs, more specific climate‐related information better supports resilience planning across multiple stakeholder groups. New suites of tools could provide necessary capacity for both short‐ and long‐term, stakeholder‐specific adaptive planning. Key Points: Water stakeholders should prepare for future droughts that will be unlike past droughtsInformation available from climate projections often does not align with the detailed information needed for water planningBetter awareness of the mismatch between available and needed information will help inform efforts to close this gap [ABSTRACT FROM AUTHOR]

Drought is one of the most widespread and destructive hazards over the Loess Plateau (LP) of China. Due to climate change, extremely high temperature accompanied with drought (expressed as hot drought) may lead to intensive losses of both properties and human deaths in future. A hot drought probabilistic recognition system is developed to investigate how potential future climate changes will impact the simultaneous occurrence of drought and hot extremes (hot days exceeding certain values) on the LP. Two regional climate models, coupled with multiple bias‐correction techniques and multivariate probabilistic inference, are innovative integrated into the hot drought probabilistic recognition system to reveal the concurrence risk of droughts and hot extremes under different Representative Concentration Pathway (RCP) scenarios. The hot‐day index, TX90p, indicating the number of days with daily maximum temperature (Tmax) exceeding the 90th percentile threshold, and the Standardized Precipitation Index are applied to identify the joint risks on the LP using copula‐based methods. The results show that precipitation will increase throughout most of the LP under both RCP4.5 and RCP8.5 scenarios of 2036–2095, while Tmax may increase significantly all over the LP (1.8–2.7 °C for RCP4.5 and 2.7–3.6 °C for RCP8.5). The joint return periods of Standardized Precipitation Index and TX90p show that fewer stations will experience severe drought with long‐term hot extremes in two future scenarios. However, some stations may experience hot droughts that are more frequent and extreme, particularly certain stations in the southwest and south‐central regions of the LP with recurrence period less than 10 years. Key Points: A modeling system is developed to investigate future characteristics of simultaneous occurrence of drought and hot extremesPrecipitation projections from PRICIS and RegCM models were jointly corrected by the multidimensional copula modelResults show that some stations in partial area of Loess Plateau may experience hot droughts that are more frequent and extreme in future [ABSTRACT FROM AUTHOR]