Abstract:

Through numerous comparison experiments and the correlation analysis at different time scales,the present study tried to get the important basis of statistic significance in aspect of the use of real-time relative changes of MODIS BT combined with field ST measurements from thermal infrared anomalies for directly investigating the short and imminent earthquake-related phenomena.Results of correlation analysis show that:1)Significant correlation exists between brightness temperature,air temperature and ground temperature in the view of the longer cycle time scale(monthly mean),even in the case of short cycle(daily means),where the correlation is significantly lower than that of longer cycle,they still have good correlations;2)The correlation between the mean brightness temperature and the surface temperature increases gradually with the increased pixel size involved.This indicates that the atmospheric and environmental effect on brightness temperature is more obvious for single pixel.Th

Key words: MODIS, brightness temperature, air temperature, soil temperature, thermal infrared, earthquake

摘要：

对MODIS卫星遥感亮温与气温、地温进行了不同时间尺度的大量的计算比对和相关性分析,以期得到直接采用实时MODIS亮温相对变化,结合地面实测地温来研究地震活动热异常的短临变化信息的具有统计意义的依据。结果表明:1)亮温与气温、地温从较长周期的时间尺度(月均值)上看,其相关性很好。而短周期(日均值)尽管明显低于较长周期,但仍然有着较好的相关性。2)通过大量计算比对发现,亮温均值与地温和气温的相关性随着像元面积的增大而逐渐升高。这表明,大气和环境的影响对单一像元而言较为明显。而这种影响可以由一定区域像元的亮温均值得到一些削弱,即一定区域的亮温均值与地温(0cm)的相关性优于单个探测像元的亮温。基于此,在研究亮温相对变化时,应尽量避免采用单一像元的亮温值,利用一定区域的像元均值可能会达到一些排除干扰的效果;3)鉴于热红外亮温数据与地表实际测到的地表温度(0cm)有着显著的相关性,将实时探测到的大面积均匀分布的亮温相对变化与地表实际测到的地表温度结合起来进行热异常变化信息研究,可望提升其可信度和有效性