青藏高原土壤砾石对能量水分输送的观测与模拟研究

Observation and Simulation of Energy and Water Transport by Soil Gravel on the Qinghai-Xizang Plateau

为了检验耦合了CLM4.5的区域气候模式RegCM4.7在加入砾石参数后对青藏高原土壤能量水分输送长期的模拟效果,因此选择青藏高原阿里站、那曲站、玛多站的观测数据和中国全球陆面再分析40年产品(CRA/Land)-逐日产品(陆面产品)对模式的模拟效果进行检验。结果表明:土壤温度的模拟效果较好,并且土壤深层较浅层相关系数更高,含砾石数据与再分析数据的偏差更小,多年数据的平均变化趋势更加统一;相较于土壤温度,土壤湿度的模拟效果稍差,尤其是在青藏高原中部,但是在青藏高原东部与西南部,模拟效果有较大提升,与再分析数据的偏差明显减小。通过连续多年的模拟发现,模式的模拟效果并未随着参数化方案的优化而逐年提升,而是在一定范围内波动,且每一年的模拟效果都较原模式在相关系数及均方根误差方面有所提升。

In order to test the long-term simulation effect of regional climate model Regcm4. 7 coupled with CLM4. 5 on soil variables in the Tibetan Plateau after gravel parameters are added,therefore,the observational data of Ngari,Nagqu and Maduo stations on the Qinghai-Xizang Plateau and the CMA’s global atmospheric ReAnalysis(CRA/Land)-daily product(Land product)were selected to test the simulation effect of the model.The results show that the simulation effect of soil temperature is better,and the correlation coefficient of deep soil is higher than that of shallow soil,the deviation between gravel data and reanalysis data is smaller,and the average variation trend of multi-year data is more uniform. Compared with soil temperature,the simulation effect of soil moisture is slightly worse,especially in the central part of the Qinghai-Xizang Plateau. However,in the eastern and southwestern parts of the Qinghai-Xizang Plateau,the simulation effect is greatly improved,and the deviation from the reanalysis data is significantly reduced. Through continuous years of simulation,it is found that the simulation effect of the model does not improve year by year with the optimization of parameterization scheme,but fluctuates within a certain range,and the simulation effect of each year is improved in correlation coefficient and root mean square error compared with the original model.