A 564-year annual minimum temperature reconstruction for the east central Tibetan Plateau from tree rings

Minimum temperatures have increased rapidly on the Tibetan Plateau (TP) in recent decades, but there is still a lack of long-term background information to evaluate the nature of the anomaly. Here we present a 709-year tree-ring width chronology from Sabina tibetica Kom. on the east central TP, with reliable coverage from 1451 to 2014. Based on the significant relationship between tree growth and annual minimum temperature (Tmin), from previous April to current March, we reconstruct the pApril-cMarch Tmin for the past 564 years. The reconstruction shows six major warm (1490-1623, 1713-1729, 1784-1812, 1868-1877, 1918-1954, 1989-2014) and six major cold (1451-1489, 1624-1712, 1730-1783, 1813-1853, 1878-1917, 1955-1988) periods during the past five hundred years. The level of warming from 1989 to 2014 is unprecedented over the past five centuries. Comparison with other minimum temperature records indicates that our Tmin reconstruction represents large-scale temperature changes on the eastern TP. The positive correlation between the Tmin reconstruction and the Atlantic Multidecadal Oscillation (AMO) suggests that the latter may have played a crucial role on multidecadal temperature variations over the east central TP, with high temperatures coincident with the warm phases of the AMO, and low temperatures related to the cold phases of the AMO, respectively.