Comparison of instrumental and interpolated meteorological data-based summer temperature reconstructions on Mt. Taibai in the Qinling Mountains, northwestern China

Abstract

Previous dendroclimatical studies have been based on the relationship between tree growth and instrumental climate data recorded at lower land meteorological stations, but the climate conditions somehow differ between sampling sites and distant population centers. Thus, in this study, we performed a comparison between the 152-year reconstruction of June to July mean air temperature on the basis of interpolated meteorological data and instrumental meteorological data. The reconstruction explained 38.7% of the variance in the interpolated temperature data (37.2% after the degrees of freedom were adjusted) and 39.6% of the variance in the instrumental temperature data (38.4% after adjustment for loss of degrees of freedom) during the period 1962–2013 AD. The first global warming (the 1920s) and recent warming (1990–2013) found from the reconstructed temperature series match reasonably well with two other reported summer temperature reconstructions from north-central China. Cold periods occurred three times during 1866–1885, 1901–1921, and 1981–2000, while hot periods occurred four times during 1886–1900, 1922–1933, 1953–1966, and 2001–2007. The extreme warm (cold) years are coherent with the documentary drought (flood) events. Significant 31–22-year, 22–18-year, and 12–8-year cycles indicate major fluctuations in regional temperatures may reflect large-scale climatic shifts.