欧亚大陆土壤焓异常持续性的时空变化特征  

Spatiotemporal characteristics of soil enthalpy anomaly persistence in Eurasia

作　　者：赵昶昱 陈海山[1,2] 孙善磊[1] 

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/气候与环境变化国际合作联合实验室/气象灾害教育部重点实验室,南京210044 [2]南京信息工程大学大气科学学院,南京210044

出　　处：《气象科学》2018年第1期19-27,共9页Journal of the Meteorological Sciences

基　　金：公益性行业(气象)科研专项(GYHY201206017);国家自然科学基金资助重点项目(41230422);江苏省自然科学基金(20151525);江苏省普通高校研究生科研创新计划项目(KYLX_0823)

摘　　要：土壤焓作为一种综合考虑地表状况(如土壤湿度、土壤温度等)的特殊陆面因子,可以直接从能量角度反映陆地下垫面的热力状况,故探讨土壤焓异常持续性的相关特征,有助于加深理解地表热力异常对气候的影响。本研究基于陆面过程模式CLM4.0模拟的土壤温度、土壤液态水和土壤固态水及土壤物质类型(IGBP地表属性),分别计算了欧亚大陆冬季和夏季土壤干物质焓、土壤液态水焓和土壤固态水焓及土壤焓(前三者之和);由于土壤温度和土壤固、液态水含量的差异,浅层土壤焓及其三个组元表现出明显的区域性和季节性特征;欧亚大陆冬季土壤焓异常持续性总体较夏季强,尤其是中高纬地区;另外,土壤干物质焓、液态水焓的纬度和季节性差异也体现在对近地面大气的热力强迫上,具体表现为土壤干物质焓、液态水焓分别与感热、潜热密切相关。本研究通过较为细致地分析土壤焓异常持续性的时空变化特征,为进一步开展下垫面热力异常(以土壤焓表征)的气候效应提供了重要的信息参考。As a special indicator of land surface, soil enthalpy comprehensively integrates effects of various land surface statuses （soil moisture, soil temperature, etc ） , and directly reflects land surface thermal conditions based on energy theory. Therefore, the ananysis on relevant features of soil enthalpy a- nomaly persistence is favorable for deeply understanding thermal impacts of land surface on climate. Based on the soil temperature, soil liquid water, soil ice and the IGBP （International Geosphere-Bio- sphere Programme） soil types across Eurasia obtained from off-line simulations of the Community Land Model （CLM4.0）, the soil solid matter, soil liquid water and soil ice enthalpy （the sum was named soil enthalpy） were estimated. Climatologically, both shallow soil enthalpy and its three components obviously differed among regions and seasons, mainly due to the differences in soil temperature, and contents of soil liquid water and ice. With respect of soil enthalpy anomaly persistence over Eurasia, it was generally more robust in winter than in summer, especially for the mid- and high-latitudes. Moreover, the closer relationships of soil solid matter enthalpy with sensible heat and soil liquid water enthalpy with latent heat indicated that soil enthalpy could impact the near surface atmosphere through the pathways of thermal heating. Importantly, the relatively comprehensive analyses on spatio-temporal characteristics of soil en- thalpy anomaly persistence in this study provided critical references for conducting researches about land surface thermal anomaly induced climate effects.

关 键 词：土壤焓 感热和潜热 持续性 季节性差异 欧亚大陆 

分 类 号：P461[天文地球—大气科学及气象学]