Winter temperature variation in the Qinghai-Tibetan Plateau in 1975-2008

With an analysis of the NECP reanalysis data and 33 a of monthly averaged winter temperature data from the plateau itself and from the 89 meteorological stations within its surrounding areas,an overall warming trend was shown.Statistical methods were used in the analysis of the winter temperature variation. In addition,as a result of the uneven distribution of the plateau stations,a preliminary analysis of change in winter temperatures was done from the vertical and horizontal directions.The result showed that,though an overall increase of winter temperature appeared in the Qinghai-Tibetan Plateau that the variation of 0.6℃/10 a,some individual regions actually cooled down.The 600 hpa temperature and temperature gradient changed along with latitude.And the warming up trend was negatively correlated with altitude increase until the cooling down trend was observed in the designated altitude.The vertical direction corresponding to the temperature,as well as the rate of warming up or cooling down is different.The most obvious change in temperatures was observed in the near surface layer within the lower altitude area of the plateau.