Abstract: In the study of application of MODIS satellite remote sensing data to earthquake prediction,the paper put forward for the first time a quantificational method for the ratio of the pixels with abnormal brightness temperature(BT)increasing and a preliminary scheme for cloud removal.The principle is that firstly,the cloudless data observed by the same satellite at the same period of time but in different days(usually 1 to 3 days)are mosaiched to get high cloudless rate data,and then the brightness temperature variation curve and mean variance of each pixel are calculated with the data from the covered area to determine daily whether the brightness temperature data of the day is normal or not at certain pixel by using twice of the mean variance as criterion.The ratio of the pixels with abnormal BT increasing can be calculated by dividing the total number of abnormal pixels with the total pixels of the whole area.Analysis on a series of recent earthquakes in Taiwan area shows that the ratio of pixels with abnormal BT increasing,which normally undulates around zero,had a sudden jump 1 to 20 days before the medium-strong earthquakes.It is expected that a new method for identifying earthquake auspice could be found through special studies in regions with frequent seismic activity by analyzing the change of ratio of the pixels with abnormal BT increasing from MODIS satellite remote sensing infrared information on which the effect of cloud has been removed to a certain extent.

Key words: MODIS, satellite thermal infrared data, ratio of pixels with abnormal brightness temperature increasing, earthquake

摘要： 首次提出了MODIS卫星遥感数据用于地震预测研究的MODIS亮温增温异常点比值定量化方法以及尽量减少云层干扰的初步方案。结合近期台湾地区一系列中强地震的震例研究,归纳了分析区域内中强地震前的MODIS亮温增温异常的量化指标。研究表明,大部分研究震例在地震发生前1～20天都出现了突跳性质的增温异常比值(活跃度)增强的情况,而正常情况下增温异常比值都在零值附近波动。利用在一定程度上排除了云层影响的MODIS卫星遥感热红外信息得到的亮温增温异常点比值的变化,在一些多震地区有针对性地系统开展研究,有望找到识别地震短临前兆的一种新方法。

关键词: MODIS, 卫星热红外, 亮温增温异常点比值, 地震