Base on NCEP/NCAR skin temperature （land surface temperature or skin temperature,LST） and ERA40 reanalysis surface soil temperature （ ECMWF-STL1 ） data, the differences and similarities in spring and summer land surface thermal conditions are evaluated from the aspects of their spatial distribution and variability. Results show that： 1 ） Temperature decreasing from the equator to the poles is found in the climatological distribution of spring land surface thermal conditions from both datasets.However,ECMWF-STL1 has higher temperatures than LST in mid-low latitude regions but lower in high latitude regions. In summer, the distributions of the multi-year mean of the thermal conditions of the global land surface that two data sets reflected are similar except for that over the Greenland. 2） In spring,both of the inter-annual variability of ECMWF-STL1 and LST in high latitude of the Northern Hemisphere is larger than that in other regions. The inter-annual variability of ECMWF-STL1 is stronger than that of LST in northern Eurasia but shows an opposite pattern in the south part. In summer, significant inter-annual variability are found in central Africa, north Eurasia and some parts of the Americas, while there are evident differences in temperature variability in the North and South America areas between the two datasets. 3 ） The first mode of EOF analysis suggests that a reversed phase of spring thermal condition variation between North and South Eurasia exists in both datasets. But the spatial patterns of thermal anomalies described by those two datasets are almost opposite in North America and Australia. In summer, the characteristics of two datasets are similar in Eurasian and Africa while not much the same in other regions. 4 ） In spring, the significant warming happens in the high latitudes of Eurasia. Compared with LST, the warming trend of ECMWF-STL1 in northern Eurasia is more significant, while cooling trend in southern is relatively weak. In summer, the spatial pattern of the warming trend of ECMWF-STL1 is similar to that of LST, but with smaller values than LST. In short, the thermal conditions described by two datasets are almost consistent in most area of Africa and Eurasia,but show evident different in Australia, Greenland, America and especially over the Tibetan Plateau.%利用目前国际上应用较为广泛的两套再分析资料：NCEP／NCAR再分析的陆地表面温度（1and surface temperature or skin temperature，简称LST）及欧洲中期天气预报中心ERA40表层土壤温度（ECMWF—STLl）资料，揭示了两组资料反映的春、夏季陆面热力状况分布特征及变率的异同。结果表明：1）两套资料的全球春季陆面热力状况气候态分布均反映出表面温度从赤道向两极递减的趋势，但在中低纬地区，ECMWF—STLl高于LST，高纬度地区情况相反。夏季，除格陵兰岛外，两套资料陆面热力状况气候态分布基本相同。2）春季ECMWF—STLl、LST变率类似，均表现为北半球中高纬地区表面温度变率大的特征。相比而言，欧亚大陆北部ECMWF—STLl变率较LST明显，南部相反。夏季，温度变率较大的区域主要位于非洲中部、欧亚大陆北部及美洲部分地区，其中，南北美洲两套资料温度变率差别较大。3）分析EOF第一模态发现，两套资料均表现出春季欧亚大陆热力状况南北反相变化的特征，澳大利亚及南北美洲地区两套资料空间分布型位相正好相反。对于夏季而言，两套资料均反映出欧亚大陆及非洲的一致性变化特征，而其他地区差别较大；4）春季增温显著的地区主要位于欧亚大陆中高纬，相比而言，欧亚大陆北部ECMWF—STLl升温较明显，南部LST降温较明显。夏季，非洲、欧亚以及北美洲地区，两套资料升降温趋势分布相似，但LST升降温幅度均较ECMWF—STLl大。总之，两套资料对热力状况的描述在非洲及欧亚大陆上相似性较大，而在澳大利亚、格陵兰岛及南北美洲地区有一定的差别。另外，对青藏高原地区的热力状况的描述两套资料差别较大。
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