We have reconstructed the Palmer Drought Severity Index (PDSI) from 1580 to 2005 for Western Tian Shan, Central Asia, using tree rings of Picea schrenkiana. The reconstruction explains 35% of the actual January–May PDSI variance during the common period 1925–2005. Split-sample validation supports our use of the reconstruction model based on the full period of reliable observational data (1925–2005). Spatial climate correlation analyses with gridded PDSI data revealed that our PDSI reconstruction represents a strong regional drought signal for Western Tian Shan. Dry periods occurred during ad 1614–1628, 1700–1722, 1758–1790, 1806–1833, 1873–1898, 1908–1936, 1943–1951, 1960–1966 and 1973–1988; while the periods of ad 1580–1613, 1629–1699, 1723–1757, 1791–1805, 1834–1872, 1899–1907, 1937–1942, 1952–1959, 1967–1972 and 1989–present were relatively wet. Our reconstruction agrees reasonably well with the dry and wet periods previously estimated from tree rings in Tian Shan. Significant spectral peaks are identified at 2–5, 60.2 and 213 years. Our reconstructed drought is significantly correlated with sea surface temperature in the North Atlantic and Indo–West Pacific Oceans. The linkages to the North Atlantic and Indo–West Pacific Oceans suggest the connection of moisture variations of Central Asia to the westerly circulation and tropical ocean–atmosphere systems.

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In this article, we developed a tree‐ring‐width chronology of Schrenk spruce (Picea schrenkiana Fisch. et Mey) in southern Kazakhstan. Climate‐growth response result showed that the precipitation from the previous June to current May was the principal limited factor of radial growth. We also obtained a 246‐year reconstruction of June–May precipitation in southern Kazakhstan. The reconstruction explains 39.7% of the variance in precipitation records during the 1902–2013 calibration periods. In addition, the precipitation over the past 246 years in southern Kazakhstan has experienced six wetter periods and seven drier ones, and the extreme drought years were 1837, 1879, 1917 and 1945. From 1985 to 2004, precipitation has experienced longer and more rapid wetting, but the trend of precipitation has decreased in the past few years. The reconstructed series of precipitation is consistent with the historic precipitation/Palmer Drought Severity Index of the western Tianshan Mountains. Here, high precipitation variability occurred during 1770–1800 and 1900‐present, while 1800–1900 was relatively calm. Meanwhile, there was large power in the 2‐ to 7‐year short‐period and over the 34‐ to 35‐ and 40‐ to 43‐year long‐periods. We suggest the precipitation variability may be associated with large‐scale oscillations in the climate system. The reconstruction sheds new light on precipitation variability and the changes in a region where the climate history over the past several centuries is poorly understood.

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We present a tree-ring based reconstruction of water-year (October-September) streamflow for the Manasi River in the northern Tien Shan mountains in northwestern China. We developed eight Tien Shan spruce (Picea schrenkiana Fisch. et Mey.) chronologies for this purpose, which showed a common climatic signal. The hydroclimatic forcing driving tree growth variability affected streamflow with a three-to four-year lag. The model used to estimate streamflow is based on the average of three chronologies and reflects the autoregressive structure of the streamflow time series. The model explains 51% of variance in the instrumental data and allowed us to reconstruct streamflow for the period 1629-2000. This preliminary reconstruction could serve as a basis for providing a longer context for evaluating the recent (1995)(1996)(1997)(1998)(1999)(2000) increasing trends in Manasi River streamflow and enables the detection of sustained periods of drought and flood, which are particularly challenging for managing water systems. Several of the reconstructed extended dry (wet) periods of the Manasi River correspond to reconstructed periods of drought (flood) in Central Asia in general and in other Tien Shan mountain locations in particular, suggesting that the analysis of Tien Shan spruce could contribute significantly to the development of regionally explicit streamflow reconstructions.