HISTORICAL LATE-SPRING-TO-EARLY-SUMMER TEMPERATURE AT QINLING MOUNTAIN RANGE INFERRED FROM MULTI-SITE TREE-RING CHRONOLOGIES ,AND THEIR RELATIONSHIP WITH NORTHERN HEMISPHERE SEA SURFACE TEMPERATURE
Tree-ring chronologies from five sites in the middle-east part of the Qinling Mountains were analyzed for regional common information using principal component analysis ( PCA ) method. The first PC ( PCI) explained the most (58. 37% )of the total variances of the five site chronologies, and hence represented a regional pattern of tree growths. PCI chronology was highly negatively correlated with the May-July mean temperature averaged from five nearby meteorological stations. Correlations of meteorological records and the PCI chronology with May-July grided temperature data ( Climatic Research Unit, CRU) were calculated to investigate if they were capable of representing regional large-scale temperature variability during 1951 ~2006. Both were significantly correlated with CRU May-July temperature over large areas of the Qinling Mountains and Huanghuai Basin (short for QMHB) .which confirmed that observed records and the PCI may reflect the regional May-July temperature variability in the QMHB. We thus consider that the PCI chronology from 1885～2006 was representative of a large area temperature history.The PCI and the meteorological records were used to investigate the influence of Northern Hemisphere SST (NHSST)on the regional temperature variability in the common period 1951 ~ 2006. The coincident significant correlation with NHSST were observed for the Western Tropical Pacific Ocean and 30° ~ 50°N Ocean region of offshore China and Japan sea warm current,and both were also correlated with the SST of West Indies of Atlantic. This result indicated that the higher SST of the above ocean domains, possibly the lower PCI and the higher temperature of QMHB region. Moreover,it suggested the possible close connection of regional temperature variations to the Warm Pool SST abnormal from the extended correlation with the warm pool in the Western Pacific. Over longer time-scale, the similar correlation patterns with SST for the western tropical Pacific Ocean were also found during the two periods ( 1885 - 1950 and 1885 ~ 2006 ) ,suggesting a close and stable connection of the regional temperature with the western tropical Pacific SST. Comparison with the weakly correlated with the offshore China, Japan sea warm current and Atlantic domains, seemed to suggest the difference of the SST domains related to regional temperature during the different period.
the Qinling Mountainstree-ring widthtemperature variabilitysea surface temperature( SST)
NETL
NSTL
万方数据
维普
