Unprecedented January–July warming recorded in a 178-year tree-ring width chronology in the Dabie Mountains, southeastern China

Abstract

Previous tree-ring studies indicate that tree growth at high elevations is strongly limited by temperatures in the southeastern China, where the climate is dominated by the East Asian monsoon. Based on this result, we built a highly replicated 202-year tree-ring width chronology from high elevation sites in the Dabie Mountains, southeastern China. The most reliable period of the chronology is from 1834 to 2011 according to a subsample signal strength cutoff of 0.85. Based on this chronology, January–July minimum temperature was reconstructed for the last 178years, with an explained variance of 57.6% during the instrumental period 1956–2010. The reconstructed temperature series matches reasonably well with three other tree-ring based temperature reconstructions at decadal time scales in the region. The coldest periods are 1891–1898 and 1904–1914, however, the longest cold period is from 1948 to 1973. The warmest period is 1990–2010. Both the recent (1990–2010) warming and recent (1948–2010) temperature increase rates are unprecedented compared with any same long period during the past 178years in the study region.