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Severe persistent drought events during the last 530 years are examined in Arid Central Asia (ACA) by using the data with proxy assimilation from the Last Millennium Climate Reanalysis project version 2.0 (LMR v2.0). According to the results from the LMR v2.0, six severe decadal droughts occurred in ACA during the last 530 years and five of them overlap with the results based on the independent reconstructions of Asian summer precipitation, such as the droughts of 1519–1538 CE, 1545–1561 CE, 1621–1658 CE, 1822–1846 CE, and 1964–1983 CE. The climate anomaly patterns are characterized by opposite anomalies between the high‐latitude and midlatitude Eurasia during the first four well‐agreement droughts, with negative precipitation and positive surface level pressure and 500‐hPa geopotential height anomalies located over midlatitude Eurasia and opposite anomalies over high‐latitude Eurasia. Whereas, during the last well‐agreement drought, opposing pattern of the climate variation observed between in ACA and in the Mediterranean with negative precipitation anomalies and positive 500‐hPa geopotential height anomalies in ACA and opposite anomalies in the Mediterranean. The positive Arctic Oscillation/North Atlantic Oscillation influence is found to dominate the droughts of 1621–1658 CE via a northward migration of the westerlies. While the last drought of 1964–1983 CE produced by the combined impacts of the negative Atlantic Multidecadal Oscillation and Pacific Decadal Oscillation via the Silk Road pattern over the midlatitude Eurasian continent. Key Points: The LMR v2.0 was able to roughly capture five severe decadal droughts occurred in ACA during the last 530 yearsThe climate anomaly patterns over Eurasia during the first four droughts are different with these patterns during the last droughtThe positive AO/NAO influences dominate the drought of 1621–1658 CE, while the negative AMO and PDO played import role on the last drought [ABSTRACT FROM AUTHOR]

Studies of the effects of large volcanic eruptions on regional climate so far have focused mostly on temperature responses. Previous studies using proxy data suggested that coherent droughts over eastern China are associated with explosive low-latitude volcanic eruptions. Here, the authors present an investigation of the responses of summer precipitation over eastern China to large volcanic eruptions through analyzing a 1000-yr global climate model simulation driven by natural and anthropogenic forcing. Superposed epoch analyses of 18 cases of large volcanic eruption indicate that summer precipitation over eastern China significantly decreases in the eruption year and the year after. Model simulation suggests that this reduction of summer precipitation over eastern China can be attributed to a weakening of summer monsoon and a decrease of moisture vapor over tropical oceans caused by large volcanic eruptions. [ABSTRACT FROM AUTHOR]