不同土壤湿度资料在太行山区的对比

Comparison of Different Soil Moisture Recorcls in the Taihang Mountains,China

利用高时空分辨率地面气象数据驱动陆面模式CLM3.5得到的土壤湿度资料,结合ERA40和NCEP-2再分析资料,系统对比分析了1980—2008年太行山区生长季（5—9月）表层（0～10 cm）土壤湿度时空变化,并利用站点观测资料（1993—2008年）对三套资料在太行山区的适应性进行了验证和比较。结果表明：CLM3.5资料和ERA40资料能较好地描述太行山区土壤湿度的年际和年内变化特征,且两者的土壤湿度呈现相对一致的＂北干南湿＂格局,其中CLM3.5资料土壤湿度的时空变率高于ERA40资料;而NCEP-2资料对土壤湿度时空分布的描述效果较差。太行山区土壤湿度与降水和相对湿度呈显著的正相关,与气温呈显著的负相关,实际条件下土壤湿度与气候变化的相互作用机制更加复杂。

A sets of soil moisture data produced from CLM3.5 driven by the China Meteorological Forcing Dataset, and two widely-used re-analysis soil moisture datasets （ERA40 and NCEP -2 ） were used to systematically and comparably analyze the spatial-temporal variations of surface （0 -10 cm） soil moisture in the growing season （May to September） over the Taihang Mountains from 1980 to 2008, and matched them with observational data within the same study area. Results show that CLM3.5 data and ERA40 data are generally consistent well with the observations, and both exhibits a relatively consistency of spatial distribution of soil moisture, namely dry in the north while wet in the south, in which spatio-temporal variability of soil moisture simulated by CLM3.5 is larger than that of ERA40 data. However, NCEP- 2 doesn＇t describe the spatio-temporal distribution of soil moisture well. Moreover, soil moisture has significantly positive correlation with Mountains, wheraes negative correlation with air temperature. tween soil moisture and climate change is more complex.