Soil temperature is a key driver of several physical, chemical, and biological processes. The Environmental Policy Integrated Climate (EPIC) is a comprehensive ecosystem model that simulates soil temperature dynamics using a cosine function approach driven by daily air temperature and average annual soil temperature at damping depth, which may erroneously predict lower soil temperatures in winter. A new cosine model and a pseudo-heat-transfer model were therefore developed and implemented for simulating soil temperature. The two methods were evaluated by comparing simulated daily soil temperatures with observed data at 24 study sites. Results showed that the two new methods had similar performance and the better statistical results obtained with these new methods demonstrated the ability to better predict the soil temperature for a wide range of pedoclimatic conditions, land management, and land uses. The main reason for the improved performance was due to a better prediction of soil temperature during the winter period.

土壤温度是几个物理、化学和生物过程的关键驱动因素。环境政策综合气候 (EPIC) 是一种综合生态系统模型，它使用余弦函数方法模拟土壤温度动态，该方法由阻尼深度处的日气温和年平均土壤温度驱动，可能会错误地预测冬季较低的土壤温度。因此，开发并实施了一种新的余弦模型和伪传热模型来模拟土壤温度。通过将模拟的每日土壤温度与 24 个研究地点的观测数据进行比较，对这两种方法进行了评估。结果表明，这两种新方法具有相似的性能，并且使用这些新方法获得的更好的统计结果表明能够更好地预测各种土壤气候条件、土地管理和土地利用的土壤温度。性能提高的主要原因是对冬季土壤温度的更好预测。