中强地震前的长波辐射异常震例研究

Anomalies of Outgoing Longwave Radiation before Some Medium to Large Earthquakes

文章利用NOAA提供的1°×1°长波辐射产品对2008年发生在我国的三次地震(2008年8月25日仲巴6.8级地震、5月12日汶川8.0级地震和3月21日于田7.3级地震)进行了研究。通过滑动平均,标准方差阈值等方法分析了各地震震前2个月和震后2个月的长波辐射日数据的时间序列,分析结果表明在震前40余天到震前几天均出现不同程度的长波辐射异常,这些异常可能与地震相关,并且异常的幅度和震级不是简单的线性关系。

Three medium to large earthquakes happened in China in 2008, including the 25 August Zhongba Ms6. 8 earthquake, the May 12 Wenchuan MsS. 0 earthquake and 21 March Yutian Ms7.3 earthquake. These three earthquakes have been studied using outgoing longwave radiation （OLR） 1°×1° grid data provided by NOAA（National Oceanic and Atmospheric Administration）. The daily OLR data two months before and after the seismic events have been analyzed using moving average, standard threshold and so on. It is shown that the OLR anomalies have been found about 40 days to several days before the seismic events. These anomalies may have some relationship with the seismic events, but the relationship between the abnormal magnitude and earthquake magnitude were not simply linear.