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Co-occurring extreme heat, drought, and moisture events are increasing under global warming and pose serious threats to ecosystem and food security. However, how to effectively link compound agrometeorological disasters (CADs) with climate change has not been well assessed. In this study, we focus on the comprehensive influence of large-scale climate factors on CADs rather than extreme meteorological elements. The results indicate that there are two main CADs of spring maize in Shenyang, Northeast China (NEC), including concurrent drought and cold damage (DC) and drought in multiple growth periods (MD). The related circulation anomalies at mid–high latitudes are identified as four patterns, namely, the Northeast Asia Low (NEAL) and Ural High (UH) patterns affecting DC, the Baikal High and Okhotsk Low (BHOL), and the Northeast Asia High (NEAH) patterns leading to MD. The vertical profile and water vapor transport anomalies further demonstrate the influence mechanism of large-scale circulation on compound heat–moisture stresses. This study highlights the role of atmospheric circulation, which can provide effective predictors for these synergistic agrometeorological disasters. [ABSTRACT FROM AUTHOR]

The frequency of extreme drought events in northeastern China (NEC) has increased since the 2000s, and such a decadal anomalous trend may lead to significant stress on agriculture and economic development. The correlation between Arctic sea ice loss in spring and extreme summer droughts over NEC was investigated. The results show that the loss of sea ice over the Barents Sea in spring is associated with extreme droughts and positive height anomalies over NEC in summer. The physical processes include two pathways. First, sea ice loss from the Barents Sea to the Kara Sea results in reducing baroclinicity over the ice loss region but increasing baroclinicity over the ice melting region, which is favorable to the wave ridge over northern Europe and negative-phase Summer North Atlantic Oscillation (SNAO). One wave train originates from negative-phase SNAO over North Atlantic–Europe and spreads to central Europe, central Asia, and NEC. Second, another wave motion flux originates from the Barents–Kara Sea propagating eastward, and then disperses southward to NEC. Both wave trains lead to anomalous anticyclonic circulation and westward subtropical high, which favors descending motion and less water vapor flux, thereby contributing to extreme drought. [ABSTRACT FROM AUTHOR]

The prolonged droughts that frequently occur in northern China are related to persistent anomalies of circulation and the low‐frequency waves. To explore the formation of the low‐frequency waves and the related internal variability and external forcing, the intra‐seasonal kinetic energy (KE) and the corresponding energy transfer terms are investigated algorithmically with multiscale energy and vorticity analysis. The results show two major energy sources located over the central North Atlantic (NA) and Europe, with increasing baroclinicity and energy conversion. The major energy conversion is from basic flow to intra‐seasonal KE, which corresponds to a southeastern extension of NA jet stream (JS) exit and the northward shift in the entrance of Afro Asian JS. JS shifts are helpful to the conjunction of both JS, and thereby enhance JS waveguide and wave energy dispersion. In addition, with increasing surface temperature and diabatic heating over Europe and the Mediterranean Sea, there are increase baroclinicity that facilitates the buoyancy energy conversion, ascending KE flux and positive pressure flux in the lower troposphere, those result in higher mid‐upper‐troposphere KE. The divergent energy contributes to the development and enhancement of the low‐frequency waves, favouring the extratropical eddy, wave structure, and quasi‐stationary waves amplitude, which is thereby conducive to magnified wave amplitude and extreme droughts in northern China. The results emphasize the internal dynamics and local forcing and provide prediction reference for extratropical extremes. [ABSTRACT FROM AUTHOR]

The frequency of extreme drought events in northern China has increased since the mid‐1990s, and such a decadal anomalous trend may have a vital influence on national economics and food supply. Based on the analysis of observational datasets and experiments conducted by a linear baroclinic model, this study claims that the intraseasonal circulation anomalies related to extreme drought are linked to the eastward shift in the negative phase of the summer North Atlantic Oscillation (SNAO). When the SNAO is in a negative phase, the cyclonic eddy‐driven jet can enhance the eastward extension of the North Atlantic jet stream (NAJS), contributing to a closer connection between the NAJS and the Asian‐African jet stream and enhancing the waveguide. The cyclonic eddy in the exit of the jet stream excites anomalous Rossby wave energy that originates from the NAJS exit and spreads to the Caspian Sea, Mongolia, and northern China; this associated wave train, which is similar to the Silk Road Pattern (SRP), enhances the anticyclonic anomaly over northern China, establishing a pronounced link with extreme drought in northern China. Thus, the negative phase of the SNAO may be a contributing driver of extreme drought in northern China. Key Points: The extreme drought events in northern China are linked to the eastward shift of the summer North Atlantic Oscillation (SNAO)Cyclone eddy‐driven jet can enhance east extension of North Atlantic jet stream (NAJS) when the SNAO is in the negative phaseThe cyclonic eddy excites anomalous Rossby wave energy originating from the NAJS exit, which enhances the anticyclonic anomaly over northern China [ABSTRACT FROM AUTHOR]

• Assessed water supply risks in SSP–RCPs for climate adaptation policy development. • Combined effects of climate and LUCC to project water supply risks. • Analyzed the change of climate, LUCC and water supply by SD-PLUS-SWAT model. • Medium-radiative-force scenario showed the risk of seasonal drought and flooding. Coupling land use and climate change under shared socioeconomic pathway and representative concentration pathway (SSP–RCP) scenarios can provide more accurate predictions of water supply risks, thereby supporting decision-making for spatial planning with a focus on climate adaptation. Climate change exhibits spatial and temporal differences. To meet the requirements of spatial planning, further research is needed to assess water supply risks at different basin or regional scales. In this study, we selected four SSP–RCP scenarios for analysis, considering the temporal scale of spatial planning. The climate modeling capabilities of five global climate models (GCMs) and a multi-model ensemble (MME) were evaluated using a Taylor diagram, which assesses the performance of climate element simulations. The modeling framework that consisted of system dynamics (SD), patch-generating land-use simulations (PLUS), and Soil and Water Assessment Tool (SWAT) was employed to analyze synergistic changes in climate, land use, and water supply. The Ganjiang River Basin (GRB) serves as a case study for climate-adaptive planning at the basin scale, given its characteristics of high agricultural water demand and vulnerability to droughts and floods. The study aims to provide decision-making support for such planning. In our projections, precipitation in the GRB showed a slightly increasing trend from 2021 to 2050. Monthly precipitation increases during the flood season in August and decreases during the dry season from October to December. The maximum and minimum temperatures showed an increasing trend on both the yearly and monthly scales, with slightly higher increases during fall and winter. During the planning phase, the land use quantities of SSP126 and SSP245 showed similar variations. SSP370 experienced the most significant reduction in farmland, while SSP585 displayed a more scattered and punctuated layout of construction land. The annual water supply in the GRB showed a slightly decreasing trend from 2021 to 2035 and 2036–2050, and the largest reduction was found in SSP370. The trend of variation in the monthly water supply was complex. There was a consistent trend of decreasing water supply during the dry season, whereas the changes during the flood season were more complex. Seasonal variations in water supply are a major water security concern for the basin's future. It is necessary to strengthen the agricultural water security planning in the northern region of the basin and enhance its ability to adapt to droughts and floods. [ABSTRACT FROM AUTHOR]