Acta Geographica Sinica ›› 2018, Vol. 73 ›› Issue (1): 13-24.doi: 10.11821/dlxb201801002

• Climate Change • Previous Articles     Next Articles

Spatiotemporal variability of temperature in northern and southern Qinling Mountains and its influence on climatic boundary

LI Shuangshuang1,2(),LU Jiayu1,2,YAN Junping1,2(),LIU Xianfeng1,2,KONG Feng3,WANG Juan4   

  1. 1. School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China
    2. National Demonstration Center for Experimental Geography Education, Shaanxi Normal University, Xi'an 710119, China
    3. Research Centre for Strategic Development, China Meteorological Administration, Beijing 100081, China
    4. Shaanxi Meteorological Administration, Xi'an 710119, China
  • Received:2017-03-30 Online:2018-01-31 Published:2018-01-31
  • Supported by:
    National Natural Science Foundation of China, No.41701592;Fundamental Research Funds for the Central Universities, No.GK201703048;National Social Science Foundation of China, No.14AZD094

Abstract:

A study on temperature variations in the northern and southern Qinling Mountains is performed using temperature series at 70 meteorological stations for the period 1970-2015. Temporal trends, spatial characteristics, 0 ℃ isotherm displacement and the number of days with active accumulated temperature above 10 ℃ are evaluated, using extreme-point symmetric mode decomposition (ESMD), spatial analysis and other climate diagnosis methods. The significance of climatic boundary line of the Qinling Mountains is explored in the context of global warming. Four new insights have been achieved: (1) The changing trends of temperature in the northern and southern Qinling Mountains over the past 46 years are synchronous, with the warming process shown as a 'non-smooth, nonlinear, and ladder-shaped' pattern. The evolution process can be divided into three periods: the low stationary fluctuation period in 1960-1993, followed by a rapid increase period in 1994-2002, and finally a warming stagnation period in 2003-2015. (2) The ESMD decomposition indicates that the changing trends of temperature over the northern and southern Qinling Mountains are dominated by interannual fluctuation, and have no obvious linear trend. (3) The spatial variation of temperature in the Qinling Mountains is characterized by 'synchronous warming, and differential north-south change'. In the north, the spatial variation of temperature is relatively consistent, while in the south low temperature centers are observed at Xixiang-Ankang basin and Shangdan basin. (4) The Qinling Mountains, as a climatic boundary line, still play a major/obvious role; however, there exists difference in the response of temperature variations to global warming over the north and south of the Qinling Mountains. The northern boundary of north subtropical zone extends upward along the southern Qinling Mountains; while warming zone extends by the form of enclave in the northern Qinling Mountains due to rapid urbanization and mountain blocking.

Key words: temperature, extreme-point symmetric mode decomposition, north and south transitional zone of China, Qinling Mountains