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Abstract: Snow cover is a common and relatively stable land cover condition in winter for cold north regions in China. Snow cover has significant effects on water and heat transfers in frozen soil; it needs to be considered in the study of frozen soil water–heat coupled movements. On the basis of previous research results and physical process analysis of water and heat movements in snow cover and soil, a snow cover–soil union water–heat coupled movements model is established in this paper. The numerical simulation was conducted by using a finite difference method. The results indicate that the simulated values have a similar trend to the measured values and the numerical simulation had big relative errors. However, the average absolute errors of the total and liquid moisture content in frozen soil were all less than 4%, and that of the frozen soil temperature was 1.37 °C. The errors of the numerical simulation were still within the acceptable range. Thus, the snow cover–soil union water–heat coupled movement model constructed in this paper is rational. [Copyright &y& Elsevier]

Abstract: In this paper, a frozen soil parameterization scheme is developed based on the Common Land Model. We modify a frozen soil parameterization scheme using soil matric potential to define maximum liquid water content when soil temperature is below the freezing point; the simulation performance is validated using the data from Maqu station on the Tibetan Plateau from 2005 to 2006. The simulated results indicate that the modified frozen soil parameterization scheme allows the liquid water to exist when the soil temperature is below the freezing point, and the simulated soil liquid water content is significantly improved. The simulated soil temperature is also improved because of the successful simulation of the soil liquid water content. The distribution of energy from the modified model is closer to the observed data. Also, the simulated latent heat flux from the modified model increases and the simulated soil heat flux descends compared with the original model. [Copyright &y& Elsevier]