img

Wechat

Adv search

Journal of Desert Research ›› 2024, Vol. 44 ›› Issue (1): 61-74.DOI: 10.7522/j.issn.1000-694X.2023.00068

Previous Articles     Next Articles

Dynamic downscaling simulation of temperature and precipitation in the Qilian Mountains and its surrounding areas

Xia Li1,2(), Bao Yang1()   

  1. 1.Key Laboratory of Desert and Desertification,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China
    2.University of Chinese Academy of Sciences,Beijing 100049,China
  • Received:2023-03-12 Revised:2023-05-16 Online:2024-01-20 Published:2023-12-26
  • Contact: Bao Yang

Abstract:

The study region is located in the Qilian Mountains and its surrounding areas, which are sensitive zone for monsoon-westerly interaction, and have complex climate change mechanisms. In this paper, a one-year sensitivity test was conducted to select the optimum parameterization scheme combination from five sets of schemes. With the optimum parameterization setting, a ten-year dynamic downscaling simulation of the study region was carried out over the period 2005-2014 using the regional climate model WRF driven by bias-corrected CMIP6 data. The results show that: (1) The WRF model is capable to simulate the air temperature well; different Parameterization scheme combinations perform weak effect on the simulation of temperature whilst the simulation of precipitation by the WRF model is more influenced by the parametric scheme combinations; and the simulation accuracy of precipitation is generally poorer than that of temperature. Sensitivity tests on the Parameterization scheme combinations show that the parametric scheme combination of the Thompson cloud microphysics scheme, Grell-D cumulus convection scheme, RRTM-Dudhia radiation physics scheme, and Noah land surface process scheme is the most suitable for the Qilian Mountains and surrounding areas. The results of the sensitivity tests on topographic data show no significant improvement in the simulation of temperature and precipitation. (2) The spatial distribution characteristics of simulated temperature and precipitation are generally able to reproduce the observed datasets. The spatial distribution of temperature and precipitation is greatly influenced by the altitude, with lower temperature but more precipitation at the higher altitudes than the surrounding lower altitudes; the correlation coefficients between the simulated and observed temperature is much significant than that on precipitation. Simulation biases are mainly identified in the underestimation of temperature but overestimation of precipitation. At the station sites, both simulated temperature and precipitation have almost identically normal distribution patterns for observed temperature and precipitation, specifically with deviations in winter temperature and summer precipitation simulations at each station.

Key words: WRF, the Qilian Mountains, parametric scheme evaluation, dynamic downscaling

CLC Number: