Long-term variation of temperature over North China and its links with large-scale atmospheric circulation

A May-July temperature reconstruction is based on tree-ring widths of Chinese pine (Pinus tabulaeformis) from Ningwu, Shanxi Province, China. The reconstruction explains 45.1% of the variance in observed May-July temperature. The intervals with persistent decadal warmth include 1779-1792, 1827-1839, 1853-1865, 1898-1932, 1936-1948 and 1987-2003. Intervals with persistent decadal cold include 1793-1807, 1814-1826, 1866-1888, 1949-1963 and 1976-1986. Spatial correlation between the reconstruction and the gridded temperature datasets reveals that the reconstruction is representative of temperature variability in semi-arid/arid regions of East Asia, including the Gobi Desert, the Loess Plateau and the North China Plain. The regions are referred to as North China in this study. Significant correlation with the January-August temperature reconstruction in the Helan Mountains of Northwest China for the overlapping period of 1796-1999 suggests that the reconstruction captures the regional temperature variability for a long-term period. The reconstructed temperature series has a significantly negative correlation with the monsoon rainfall series at inter-annual, decadal and multi-decadal time scales for the overlapping period of 1688-2003, suggesting an influence of the East Asian Summer Monsoon (EASM) and the dominant climate regime consisting of either cool/wet or warm/dry weather in the North China. Moreover, for the past three centuries, synchronous variations are found for the reconstructed temperature as well as the reconstructed Asian-Pacific Oscillation (APO) and the Pacific Decadal Oscillation (PDO) at decadal and multi-decadal time scales, suggesting the influences of large-scale atmospheric circulations on temperature variability in the North China. The possible mechanisms behind these links are also explained with observed climate data. (C) 2012 Elsevier Ltd and INQUA. All rights reserved.