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In this study, 85 tree cores from 45 Schrenk spruces (Picea schrenkiana) were used to establish a regional tree‐ring chronology. A 256‐year pJune–May precipitation (where p denotes a month from the previous year) for northern Kyrgyzstan in central Asia was reconstructed using this newly developed chronology. The tree‐ring‐based precipitation reconstruction tracks the observed data well (r =.622, p <.0001, n = 105). Spatial correlation proved that the reconstructed precipitation series contains climatic signals representative of a larger area, including eastern Kyrgyzstan and parts of Kazakhstan. A comparison between the newly reconstructed precipitation series and four tree‐ring‐based precipitation reconstructions for the surrounding areas reveals similar variations, particularly in the high‐frequency domain. Furthermore, this reconstructed precipitation series matches nine flood (1785, 1786, 1792, 1952, 1953, 1970, 1971, 1973, and 2000) and four drought (1917, 1919, 1927, and 1944) events noted in the historical documents and captures a dry decade that occurred in the 1910s in central Asia. [ABSTRACT FROM AUTHOR]

Using the reanalysis data and local weather station data, the relationship between El Niño and Southern Oscillation (ENSO) and the summer precipitation over Northwest China (SPNWC) is investigated. A pronounced rainfall response is observed in post‐ENSO summer, especially over North Xinjiang and Yili River valley. A possible mechanism is proposed for such a seasonal lagged impact. El Niño could induce Indian Ocean warming that persists into boreal spring and summer although El Niño itself has dissipated. The warmer Indian Ocean sea surface temperature (SST) would heat the tropospheric atmosphere and elevate the tropical geopotential height at the upper level. As a result, the South Asian High (SAH) exhibits a southward extension due to the increasing geopotential height in its southern flank. A southward displacement of subtropical jet is evident associated with such SAH shift, which further induces a barotropic low pressure anomaly over central Asia. Meanwhile, associated with the southward displacement of subtropical jet, the water vapor from tropical Indian Ocean tends to transport across Iranian Plateau and bring wet and warm air into central Asia. The resultant convergence of water vapor with cold and dry air from high latitude leads to the observed rainfall anomaly to the south and east of Balkhash Lake, explaining the lagged relationship between ENSO and SPNWC. Our results have potential applications on the seasonal prediction of SPNWC. [ABSTRACT FROM AUTHOR]