Spring Hydroclimate Reconstruction on the South‐Central Tibetan Plateau Inferred From <i>Juniperus Pingii</i> Var. <i>Wilsonii</i> Shrub Rings Since 1605

Abstract

Abstract Alpine regions on the Tibetan Plateau are sensitive to climate change, however, little is known about their long‐term hydroclimate variability due to short and few instrumental records. Alpine shrub provides a rare opportunity to reconstruct past high‐resolution hydroclimate conditions. Here, we used living and dead juniper shrubs ( Juniperus pingii var. wilsonii ) to develop a 537‐year ring width chronology nearby the Nam Co Lake (4,725 m a.s.l.). The chronology explained 46% of variance in May–June Standardized Moisture Anomaly Index (SZI) in the period from 1970 to 2010. We reconstructed May–June SZI since 1605. The reconstructed SZI matched well with several tree‐ring based moisture or drought reconstructions for the Tibetan Plateau. In particular, two long dry May–June periods of 1637–1683 and 1708–1785 during the Little Ice Age (LIA) implied that long‐term cold temperature tends to slow down hydrological cycle in the margin areas of the Indian summer monsoon.