基于MODIS数据的宁夏地表温度空间分布研究  

Spatial distribution characteristics of land surface temperature retrieved from MODIS data in Ningxia Hui Autonomous Region

作　　者：杜灵通[1] 李国旗[1] 

机构地区：[1]宁夏大学西北退化生态系统恢复与重建省部共建教育部重点实验室,宁夏银川750021

出　　处：《干旱地区农业研究》2008年第6期191-195,共5页Agricultural Research in the Arid Areas

基　　金：国家自然科学基金(30660039)

摘　　要：在分析现有分裂窗算法的基础上,选择了一种适合于MODIS数据的简化分裂窗算法,针对MODIS的热红外波段数据,讨论了利用该分裂窗算法反演地表温度所需的亮度温度、大气透过率及地表比辐射率的计算方法,并对宁夏的地表温度进行了反演。结果表明,宁夏的地表温度从南到北表现出三个明显的区域,采用30 km×30 km的样区,对这三个区域的地表温度进行统计得出,南部山区的地表温度分布在19.7～35.3℃之间,且在这一温度段内分布均衡,平均地表温度为27.1℃;灌区的地表温度分布在25.9～37.1℃之间,且主要靠近低温区段,平均地表温度为29.3℃;中部干旱带的地表温度分布在31.2～48.9℃之间,且主要靠近高温区段,平均地表温度为45.8℃。这些特征与宁夏的陆面植被覆盖、地形特征等实际状况相符。The split window algorithm is a kind of simplified algorithm that is suitable for MODIS data. For retrieving the land surface temperature, the paper discussed the calculation of some parameters, for example, brightness temperature, atmospheric transmittance, surface emissivity. In general, the brightness temperature can be calculated from band 31 and band 32 using Planck Radiation Function. The atmospheric transmittance is usually simulated by atmospheric water vapour content which can be calculated from band 2 and band 19. The surface emissivity of earth can be calculated by normalized difference vegetation index （NDVI） that deduced from band 1 and band 2 in MODIS data. Based on this simplified split window algorithm, the paper retrieves the land surface temperature of Ningxia Hui Autonomous Region. The results show that there are three different land surface temperature regions from south to north. We select a 30 km × 30 km sample area in each regions and analyze their land surface temperature. In mountain regions of southern Ningxia, the land surface temperature distributes from 19.7℃ to 35.3℃ and it distributes averagely in the range. The average land surface temperature of mountain regions of southern Ningxia is 27. 1℃. The land surface temperature of irrigation regions distributes in 25.9-- 37.1℃ and the main temperature point near in the low temperature part. The average land surface temperature of irrigation regions is 27. 1℃. The land surface temperature of Ningxia middle arid regions distributes in 31.2-48.9℃ and the main temperature point near in the high temperature part. The average land surface temperature of this regions is 45.8℃. All these temperature characteristics are matched with the Ningxia land surface characteristics, such as vegetation coverage, elevation, forest distribution, etc.

关 键 词：MODIS 地表温度 空间分布 分裂窗算法 宁夏 

分 类 号：S161.23[农业科学—农业气象学]