Seismic triggering of atmospheric variables prior to the major earthquakes in the Middle East within a 12-year time-period of 2002–2013

Abstract

Several studies have reported the increased values of surface-latent heat flux (SLHF) and rainfall events prior to the earthquakes as the seismic precursors. In order to investigate the variation of two mentioned atmospheric variables, we analyzed 39 major earthquakes in the Middle East based on the time series of NASA remote sensing data. On this basis, we observed that accumulated rainfall and SLHF of about 29 earthquakes were higher than 10 mm and 50 W/m2, respectively (~75 %), over 3–23 days prior to the main shock of major earthquakes. We believed that the records of atmospheric variables are the consequence of a seismic-triggered chain including of air ionization, surface-latent heat exhalation, water vapor condensation and subordinate rainfall as the atmospheric responses to lithospheric motions. This seismic triggering in the Middle East has averagely caused to accumulated rainfall of ~35 mm and maximum SLHF of ~115 W/m2 over the 3–23 days prior to 39 major earthquakes. To investigate of spatial correlation between earthquakes and atmospheric variations, we clustered 39 major earthquakes in eight seismological regions. Then, we estimated the moderate and strong correlation (R 2) between preceding times of earthquakes with magnitude of major earthquakes and their hypocenter depth equal to 0.48 and 0.68, respectively.