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Using the southern limit of snowfall recorded in Chinese documents, chronologies of tree-ring width, and tree-ring stable oxygen isotope (δO), the annual temperature anomaly in southern China during 1850-2009 is reconstructed using the method of signal decomposition and synthesis. The results show that the linear trend was 0.47°C (100 yr) over 1871-2009, and the two most rapid warming intervals occurred in 1877-1938 and 1968-2007, at rates of 0.125°C (10 yr) and 0.258°C (10 yr), respectively. The decadal variation shows that the temperature in the moderate warm interval of the 1910s-1930s was notably lower than that of the 1980s-2000s, which suggests that the warming since the 1980s was unprecedented for the past 160 years, though a warming hiatus existed in the 2000s. Additionally, there was a rapid cooling starting from the 1860s, followed by a cold interval until the early 1890s, with the coldest years in 1892 and 1893. A slight temperature decline was also found from the 1940s to the late 1960s. This study provides an independent case to validate the global warming for the past 160 years and its hiatus recently, because the proxy data are not affected by urbanization. [ABSTRACT FROM AUTHOR]

This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50-70-yr, 100-120-yr, and 200-250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3°C and 0.7°C, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870-2000, at a rate of 0.56° ± 0.42°C (100 yr); however, temperatures recorded in the 20th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981-1100 and AD 1201-70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°-30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20th century warming can primarily be attributed to a mega El Ni˜no-Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China. [ABSTRACT FROM AUTHOR]