Sensitivity Study of a Parameterised Scheme for Land Surface Latent Heat Flux based on BCC_AVIM

Expand
  • 1. College of Atmospheric SciencesChengdu University of Information Technology /Chengdu Plain Urban Meteorology and Environment Sichuan Provincial Field Scientific Observation and Research StationChengdu 610225SichuanChina
    2. Earth System Numerical Prediction CenterChina Meteorological AdministrationBeijing 100081China
    3. Key Laboratory of Cryospheric Science and Frozen Soil EngineeringNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000GansuChina
    4. College of Optoelectronic EngineeringChengdu University of Information Technology /Chengdu Plain Urban Meteorology and Environment Sichuan Provincial Field Scientific Observation and Research StationChengdu 610225SichuanChina

Online published: 2025-04-11

Abstract

The BCC_AVIM model neglects the effects of molecular diffusion ratevegetation litter and dry sur‐ face layer thickness on water vapour conductivity in the simulation of latent heat fluxes at the land surface. Based on thisthis paper considers the above detailed physical processes for the simulation of latent heat fluxes at the land surfaceand focuses on the effects of these processes on the simulation. The physical processes considered mainly include1the diffusion rate of molecules through the soil pores to the drying surface layer and the effect of plant apoplastic cover on the water vapour conductivitySakaguchi and Zeng2009hereafter referred to as the S-Z scheme);(2the effect of the thickness of the drying surface layer of soil on the water vapour conductivitySwenson and Lawrence2014hereafter referred to as the S-L scheme);and3the effect of physical processes on water vapour conductivity in the combined S-Z and S-L schemeshereafter referred to as the SZ-SL scheme. In order to better study its sensitivity in different subsurfacesobservations from the flat and uniform al‐ pine meadow Maqu station and the complex topography of Si'e Mountain station in Southern Sichuan Forest were selected to examine the simulated effects of different parameterisation schemes. The results are as follows:(1The BCC_AVIM model can better reproduce the trends of soil temperature and humiditysensible latent heat fluxes and other elements at Si'e Mountain and Maqu stationsbut the simulated values deviate from the measured values to a certain extent;(2Based on the BCC_AVIM modelthe simulated latent heat fluxes at the two stations are significantly improved by the introduction of more detailed physical processeswith the simulated results of the S-Z scheme being the closest to the measured valuesand the simulated results of the S-Z scheme being the closest to the measured values. were closest to the measured valueswith the Pearson's correlation coefficientRof Si'e Mountain station improved from 0. 68 to 0. 74the mean absolute percentage errorMAPEreduced by 10. 7%and the root mean square errorRMSEreduced by 4. 0 W·m-2the R of Maqu station was improved from 0. 15 to 0. 62the MAPE was reduced by 5. 7%and the RMSE was reduced by 11. 2 W·m-2; (3the simulation results of the two stations' soil temperature and humidity simulation results show that com‐ pared with the original schemethe scheme after considering more detailed physical processes increases the simulated values of soil temperature and soil humidity and enhances the correlation with the measured valuesof which the S-Z scheme is the optimal scheme for soil temperature simulation at the two stationsthe S-L scheme is the optimal parameterization scheme for soil humidity simulation at Si'e Mountain stationand the SZ-SL scheme is the optimal parameterization scheme for soil moisture simulation at Maqu station. scheme;(4by considering more detailed physical processesnot only the simulation accuracy of latent heat fluxes is significantly improvedbut also the simulation ability of soil temperature and soil moisture is enhancedbut the improvement of sensible heat fluxes is still limited.

Cite this article

LIN Zhaoyu, ZHANG Yu, WU Tongwen, SU Youqi, WANG Shaoying, MA Xiangyi . Sensitivity Study of a Parameterised Scheme for Land Surface Latent Heat Flux based on BCC_AVIM[J]. Plateau Meteorology, 0 : 1 . DOI: 10.7522/j.issn.1000-0534.2025.00021

Outlines

/