Acta Geographica Sinica ›› 2015, Vol. 70 ›› Issue (3): 407-419.doi: 10.11821/dlxb201503005

• Orginal Article • Previous Articles     Next Articles

Implication of the heating effect of the Tibetan Plateau for mountain altitudinal belts

Yonghui YAO1(), Mei XU2, Baiping ZHANG1,3()   

  1. 1. State Key Laboratory of Resource and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    2. Institute of Water Resources and Hydropower Research, Beijing 100044, China
    3. Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China
  • Received:2014-11-30 Revised:2015-01-27 Online:2015-03-20 Published:2015-03-20
  • Supported by:
    National Natural Science Foundation of China, No.41001278, No.41030528

Abstract:

The immense and towering Tibetan Plateau (TP) acts as a heating source and shapes the climate of both the Eurasian continent and the entire world. The heating effect of the TP was first noticed by meteorological scientists in the 1950s due to the important implications of the plateau for Asian climate. Most researches focused on its role as the heat source in summer and its implications for Asian climate, but little has been done on the quantitative information about the heating effect of the plateau and its implications for the position of mountain altitudinal belts (MABs). Using estimated air temperature data, observed meteorological data, MAB / treeline data and ASTER GDEM data, this paper compares the position / height of MABs and alpine treelines between the main TP and the surrounding mountains / lowland and explains the spatial pattern of MAB / treeline of TP from the point of view of the heating effect. The results demonstrate the following important characteristics. (1) Due to the heating effect of TP, the air temperatures and the length of growing season gradually increase from the eastern edge to the interior main TP. The monthly mean air temperature in the interior main plateau is approximately 2-7 ℃ higher than that in the surrounding mountains and adjacent lowland areas. At an elevation of 4500 m (corresponding to the mean altitude of the TP), the monthly mean temperature differences between the plateau and the Sichuan Basin range from 3.58 °C (April) to 6.63 °C (June); the height of the 10°C isotherm of the warmest month goes upward from the edge to the interior of the plateau, which is 4000 m in the Qilian Mts. and its eastern edges, while uplifts to 4600-5000 m are observed along the belt of Lhasa- Zuogong; the warmth index at the altitude of 4500 m in the interior main TP can reach 15°C / month, but it is lower than 15°C / month on the eastern edges and the northern parts of the TP. (2) In terms of air temperatures, the height of the 10°C isotherm of the warmest month and the warmth index gradually increase from the easternmost to the interior of the main plateau; MABs and treeline follow a similar trend rising inwards, the dark-coniferous forest is distributed at an altitude of 1000-1500m higher in the interior main plateau than on the eastern edges, and the alpine steppe belts are about 700-900 m higher in the interior main plateau than on the eastern edges.

Key words: Tibetan Plateau, heating effect, mountain altitudinal belt, treeline, the warmth index, the 10°C isotherm in the warmest month