CLM5.0对阿拉斯加多年冻土区土壤温度和碳循环模拟的适用性评估

Applicability evaluation of CLM5.0 in simulating soil temperature and carbon cycle in Alaskan permafrost region

气候变暖对北极多年冻土和植被产生了重要的影响。CLM(Community Land Model)是应用最广泛的陆面过程模式之一,但其中复杂的边界条件和参数化过程导致模式模拟结果存在一定的不确定性。本研究评估了CLM5.0对阿拉斯加多年冻土区表层土壤温度和碳循环的模拟能力,结果表明,CLM5.0可以捕捉到表层土壤温度的季节变化。在苔原和针叶林站点,CLM5.0在日尺度和月尺度都可以很好地模拟出总初级生产力(GPP)随时间的变化,但对净生态系统碳交换(NEE)的模拟结果存在一定的不确定性。CLM5.0可以较为合理地模拟高纬度多年冻土区的土壤温度季节变化,在未来的研究中可能还需要从结构、参数化方案等过程进行改进,从而进一步提升高纬度多年冻土区碳循环的模拟精度。

Climate warming has an important effect on Arctic permafrost and vegetation.Community Land Mod⁃el(CLM)is one of the most widely used land surface models.However,the complex boundary conditions and parameterization process lead to uncertainty of the simulated results.In this study,we evaluated the simulation performance of the surface soil temperature and carbon cycle in Alaskan permafrost region using the CLM5.0.The results showed that CLM5.0 could capture the seasonal changes of surface soil temperature.At the tundra and needleleaf forests sites,the change of gross primary productivity(GPP)with time simulated by CLM5.0 on both daily and monthly scales were well simulated.The simulated net ecosystem exchange(NEE)has certain uncertainty.This study demonstrates that CLM5.0 can simulate the seasonal changes of soil temperature in high latitudinal permafrost region,but the model may be necessarily improved in the structure,parameterization scheme to improve the simulation accuracy for the carbon cycle.