Arid Zone Research ›› 2023, Vol. 40 ›› Issue (2): 173-181.doi: 10.13866/j.azr.2023.02.02

• Weather and Climate • Previous Articles     Next Articles

The variation characteristics and influencing factors of vapor pressure deficit in Qinghai Province from 1961 to 2020

LI Suyun1,2(),QI Donglin1,2(),WEN Tingting3,SHI Feifei1,2,QIAO Bin1,2,XIAO Jianshe1,2   

  1. 1. Qinghai Institute of Meteorological Science, Xining 810001, Qinghai, China
    2. Key Laboratory of Disaster Prevention and Mitigation in Qinghai Province, Xining 810001, Qinghai, China
    3. Qinghai Climate Centre, Xining 810001, Qinghai, China
  • Received:2022-03-25 Revised:2022-11-03 Online:2023-02-15 Published:2023-03-08

Abstract:

The vapor pressure deficit can reflect the ability of the atmosphere to obtain water from the surface,which is one of the main driving factors of evapotranspiration. Clarifying the spatial and temporal variation of vapor pressure deficit (VPD) can help to investigate the response of air dryness to climate change in Tibetan Plateau. Mann-Kendall test, multiple linear regression were used to analyze temporal and spatial variation characteristics and the influencing factors of VPD before and after the breakpoint from 1961 to 2020 in Qinghai Province. The results showed that VPD had an increasing trend in Qinghai Province from 1961 to 2020 and a mutation in 1998. The seasonal averages and corresponding climatic trend rates of VPD were the same as summer>spring>autumn>winter. In different functional areas, average VPDs showed as Qaidam Basin>Eastern Agricultural Area>Qinghai Lake Area>Qingnan Pastoral Area, the corresponding climatic trend rates were the Eastern Agricultural Area>Qaidam Basin>Qingnan Pastoral Area>Qinghai Lake Area. The multi-year average VPD showed a “saddle field” distribution in space, and had an increasing trend except the Guinan Station in the northeastern of Qingnan pastoral area, which had a decreasing trend. The predominant meteorological factors of VPD were different before and after mutation in Qinghai Province. However, the highest temperature and relative humidity in general were the main factors. During the variation of VPD in the spring, summer, autumn and multi-year, the contribution rate of altitude was the highest, followed by longitude; while in winter, the contribution rate of altitude is still the highest, followed by latitude.

Key words: vapor pressure deficit, variation characteristics, influencing factors, Qinghai Province