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Reliable information on the dynamics of hydrological changes is crucial for the social and economic stabilities and sustaining developments in arid Central Asia. However, the few long‐term hydrological records limit understanding of the relationship between meltwater runoff and climate changes, because the short‐term observations show a paradoxical runoff trend with climate warming across Central Asia. Here, we made a systematic analysis on the 10Be exposure ages of the river terraces developed in the eastern Tarim Basin and reconstructed the hydrological regime changes during the past 170 ka. These data, together with the ages of the river terraces in the water source areas, suggest that the exposure ages of river terraces in the eastern Tarim Basin reflect the depositional time of alluvial sediments. The meltwater runoff displays an inverse relation with the North Hemisphere Summer Insolation and temperature changes on both orbital and millennial time scale, indicating that low temperatures favor high runoff fluxes. The observed correlation between the hydrological regimes and temperature changes suggests that the runoff will decrease and thus climate will become drying with global warming in arid Central Asia. Plain Language Summary: Reliable information on the dynamics of hydrological changes is crucial for the social and economic stabilities and sustaining developments in arid Central Asia. However, the short‐term observations show a paradoxical runoff trend with climate warming across Central Asia. In order to understand the association of hydrological regimes with climate changes in arid Central Asia, particularly the hydrological changes on the context of global warming, this study reconstructs the hydrological changes in the eastern Tarim Basin over the past 170 ka. Our results show that the high runoff occurred during low temperature periods in the past. The inverse correlation between the hydrological regimes and temperatures in this study indicates that the runoff will decrease and climate will become drying with global warming in the future. More conservative water management policies should be taken for the sustaining development and water security in Central Asia. Key Points: 10Be exposure ages of river terraces in the eastern Tarim Basin reflect the depositional dates of alluvial sedimentsThe runoff in central Asia displays an inverse relation with global temperature changesHigh runoffs and humid climates occurred during cold periods over the past 170 ka, indicating a climate drying with global warming [ABSTRACT FROM AUTHOR]

The dry‐wet abrupt alternation (DWAA) event, which is defined as the phenomenon of dry (or wet) spells abruptly following wet (or dry) spells, magnifies the influence of individual wet and dry events. The dynamic evolution of DWAA events has not been studied for different climate zones of China that is particularly susceptible to dry and wet extremes. This study explores the future changes in the abrupt alternations between dry and wet extremes across 10 climate divisions of China, with a thorough assessment of dry and wet conditions using the Standardized Precipitation Evapotranspiration Index (SPEI). We take advantage of an ensemble of regional climate model simulations including the Providing Regional Climate Impacts for Studies (PRECIS) experiment and five CORDEX East Asia experiments to produce high‐resolution climate information for a baseline period of 1975–2004 and a future period of 2069–2098. Our findings disclose that a total of 70% of China's land area suffered from the DWAA events at least once during 1975–2004. The wet‐dry alternation event is projected to become more frequent in summer, and a prominent increase in the number of dry‐wet alternation events is expected to occur in spring over most parts of China. Moreover, an increasing number of DWAA events with intensified magnitude is projected to strike the North China Plain dominated by warm temperature and humid zone, which is the most densely populated region of the country and is also the largest agriculture production area. Our findings also reveal a strong positive correlation between DWAA and heavy rainfall. The 95th percentile rainfall event contributes most to the wet‐dry alternation event for most climate divisions of China. Plain Language Summary: The emerging disaster of dry‐wet abrupt alternation (DWAA) has been receiving increasing attention due to its compound effects on agricultural production and socioeconomic development. Since China is exposed to dry and wet hydrological extremes as well as their interconnections, a first attempt is made in this study to explore the historical evolution and the future change in the abrupt shifts between dry and wet extremes for different climate divisions of China. Our findings reveal that a total of 70% of China's land area suffered from DWAA events at least once from 1975 to 2004. More importantly, the DWAA is expected to occur more frequently and intense by the end of the 21st century, especially for the North China Plain which is the most densely populated region of the country and is also the largest agricultural production area. Moreover, the summertime wet‐dry alternation is expected to become more frequent for most climate divisions of China, while the dry‐wet alternation event is projected to occur more frequently in spring over East China. These findings provide meaningful insights into the development of adaptation strategies for enhancing society's resilience to compound extremes in a changing climate. Key Points: A total of 70% of China's land area suffered from the dry‐wet abrupt alternation events at least once during 1975–2004The dry‐wet abrupt alternation events are projected to occur more frequently with greater intensity in the North China PlainThe 95th percentile rainfall event contributes most to the wet‐dry alternation event for most climate divisions of China [ABSTRACT FROM AUTHOR]