Journal of Geographical Sciences ›› 2007, Vol. 17 ›› Issue (1): 20-32.doi: 10.1007/s11442-007-0020-2

• Climate and Environmental Change • Previous Articles     Next Articles

Changes and spatial patterns of the differences between ground and air temperature over the Qinghai–Xizang Plateau

ZHANG Wengang1,2, LI Shuxun1,2, WU Tonghua1,2, PANG Qiangqiang1,2   

  1. 1. The National Field Station for Scientific Observation of Cryosphere Special Environment and Disaster over the North of Qinghai-Tibet Plateau, Golmud 816000, China|
    2. Cold and Arid Regions Environmental and Engineering Research Institute, CAS, Lanzhou 730000, China
  • Received:2006-10-20 Revised:2006-11-28 Online:2007-03-25 Published:2007-03-25
  • Supported by:

    National Natural Science Foundation of China, No.40471026; National Fund for “Western Major Plan” Broadly Item, No.90302006; Knowledge Innovation Project of CAS, No.220014-03; The National Basic Research Program (973 Program), No.2005CB422003

Abstract:

The difference between ground soil and air temperature (Ts-Ta) was studied by using the data of ground and air temperature of 99 stations over the Qinghai–Xizang (Tibet) Plateau from 1960 to 2000,and its spatial distribution and time changing tendency have been diagnosed by principal component analysis and power spectral analysis methods. The results show that the values of (Ts-Ta) are the maximum in June and the minimum in December. The first three loading eigenvectors, which reflect the main spatially anomalous structure of (Ts-Ta) over the Qinghai–Xizang Plateau, contain the contrary changing pattern between the north-western and the southeastern regions, the pattern response of the sea level elevation and the geography, and the pattern response of the distribution of the permafrost. There are four patterns of time evolution including the patterns of monotonous increasing or decreasing trends, the basic stability pattern and the parabola pattern with the minimum value. (Ts-Ta) has a periodic variation about 2 years. According to the spatial distribution of the third loading eigenvectors of (Ts-Ta) over the Qinghai–Xizang Plateau in cold season, the permafrost re-sponse region and the seasonal frozen ground response region are identified.

Key words: Qinghai–Xizang Plateau, difference between ground and air temperature (Ts-Ta), principal compo-nent, temperature subarea