Tree-ring samples from Dahurian Larch (Larix gmelinii (Rupr.) Rupr.) were collected at three sites in the northern Da Hinggan Mountains. Using samples measured by X-ray densitometry, measurements of tree-ring maximum ...Tree-ring samples from Dahurian Larch (Larix gmelinii (Rupr.) Rupr.) were collected at three sites in the northern Da Hinggan Mountains. Using samples measured by X-ray densitometry, measurements of tree-ring maximum latewood density chronologies of two sites were found to be significantly correlated with summer temperature. These two sites' tree-ring series were combined to form a single standard regional chronology. This was used to reconstruct the May-August monthly mean maximum temperature for the period 1855-2008 AD, and it explained 39.5% of the total temperature variance. In the past 154 years, there were 4 cold periods (1874-1893, 1927-1948, 1951-1960 and 1992-2002) and 4 warm periods (1855-1873, 1894-1916, 1961-1991 and 2003-2008). The summer temperature rose more obviously than that of winter in this region. Having been validated by other temperature reconstructions from the surrounding area, the reconstruction could indicate the summer temperature changes of large-scale regions.展开更多
基金supported by the National Natural Science Foundation of China (40871058)the Science and Technology Ministry Commonwealth Trade (Meteorology) Scientific Research Specialized Project (YHY200806011)the National Basic S&T Project of the Ministry of Science and Technology of China (2007FY220200)
文摘Tree-ring samples from Dahurian Larch (Larix gmelinii (Rupr.) Rupr.) were collected at three sites in the northern Da Hinggan Mountains. Using samples measured by X-ray densitometry, measurements of tree-ring maximum latewood density chronologies of two sites were found to be significantly correlated with summer temperature. These two sites' tree-ring series were combined to form a single standard regional chronology. This was used to reconstruct the May-August monthly mean maximum temperature for the period 1855-2008 AD, and it explained 39.5% of the total temperature variance. In the past 154 years, there were 4 cold periods (1874-1893, 1927-1948, 1951-1960 and 1992-2002) and 4 warm periods (1855-1873, 1894-1916, 1961-1991 and 2003-2008). The summer temperature rose more obviously than that of winter in this region. Having been validated by other temperature reconstructions from the surrounding area, the reconstruction could indicate the summer temperature changes of large-scale regions.
