1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and the Institute of Remote Sensing Applications of Chinese Academy of Sciences, School of Geography and Remote Sensing Science, Beijing Normal University, Beijing 100875, China 2. Center of the Earth Observation and Digital Earth, Chinese Academy of Sciences, Beijing 100190, China 3. National Satellite Meteorological Center, Beijing 100081, China 4. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China
Abstract：The microwave emissivity over land is very important for describing the characteristics of the lands, and it is also a key factor for retrieving the parameters of land and atmosphere. Different land covers have their emission behavior as a function of structure, water content, and surface roughness. In the present study the global land surface emissivities were calculated using six month (June, 2003-August, 2003, Dec, 2003-Feb, 2004) AMSR-E L2A brightness temperature, MODIS land surface temperature and the layered atmosphere temperature, and humidity and pressure profiles data retrieved from MODIS/Aqua under clear sky conditions. With the information of IGBP land cover types, “pure” pixels were used, which are defined when the fraction cover of each land type is larger than 85%. Then, the emissivity of sixteen land covers at different frequencies, polarization and their seasonal variation were analyzed respectively. The results show that the emissivity of vegetation including forests, grasslands and croplands is higher than that over bare soil, and the polarization difference of vegetation is smaller than that of bare soil. In summer, the emissivity of vegetation is relatively stable because it is in bloom, therefore the authors can use it as its emissivity in our microwave emissivity database over different land cover types. Furthermore, snow cover can heavily impact the change in land cover emissivity, especially in winter.
张勇攀1，蒋玲梅1*，邱玉宝2，武胜利3，施建成4，张立新1 . 不同地物类型微波发射率特征分析 [J]. 光谱学与光谱分析, 2010, 30(06): 1446-1451.
ZHANG Yong-pan1，JIANG Ling-mei1*，QIU Yu-bao2，WU Sheng-li3，SHI Jian-cheng4，ZHANG Li-xin1 . Study of the Microwave Emissivity Characteristics over Different Land Cover Types . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2010, 30(06): 1446-1451.
[1] WANG Hong-mei, WANG Kun, XIE Ying-zhong(王红梅，王 堃，谢应忠). Spectroscopy and Spectral Analysis(光谱学与光谱分析)，2009, 29(6): 1636. [2] Mtzler C. Meteorolgy and Atmospheric Physics，1994，54: 241. [3] Choudhury B J. Remote Sensing of Environment，1993，46(1): 1. [4] Lin B, Minnis P. Journal of Applied Meteorology，2000，39: 1103. [5] Prigent C, Rossow W B, Matthews E. Journal of Geophysical Research，1997，102: 21867. [6] Prigent C, Wigneron J, Rossow W B, et al. IEEE Transaction of Geosci. Remote Sensing，2000，38(5): 2373. [7] Karbou F, Prigent C, Eymard L, et al. IEEE Transaction of Geosci. Remote Sensing，2005，43(5): 948. [8] Karbou F. IEEE Transaction of Geosci. Remote Sensing，2005，43(8): 1788. [9] Prigent C, Aires F, Rossow W B. Bulletin of the American Meteorological Society，2006，87: 1573. [10] Pan G, Wang C, Wang H, et al. IEEE International Geoscience and Remote Sensing Symposium, 24-28, February, 2000, 923. [11] PAN Guang-dong, WANG Chao, ZHANG Wei-guo, et al(潘广东, 王 超, 张卫国, 等). Journal of Remote Sensing(遥感学报)，2003，7(6): 498. [12] Qiu Y, Shi J, Hallikainen M T, et al. IEEE International Geoscience and Remote Sensing Symposium, 7-11, February, 2008, 749. [13] Lebie H J. Int. J. Inf. Millim. Waves.，1989，10: 631. [14] Rosenkranz P W. Radio Science，1998，33: 919. [15] Kummerow C. J. Geophys. Res.，1993，98: 2757. [16] Prigent C, Aires F. Journal of Geophysical Research，2001，106(D18): 20665. [17] Cordisco E, Prigent C, Aires F J. Geophys. Res.，2006，111(D19)：1. [18] Pampaloni P. Waves in Random and Complex Media，2004，14: 275. [19] CHE Zong-xi, JIN Ming, ZHANG Xue-long, et al(车宗玺, 金 铭, 张学龙, 等). Journal of Glaciology and Geocryology(冰川冻土)，2008，30(3): 392.
