| Summary: | Earthquakes can generate thermal anomalies in the atmosphere at low altitudes. Pending well-focused detailed studies, such phenomenon may be referred to as a precursor for earthquake prediction. However, today the pre-earthquake thermal anomalies are not clear enough. In this paper, the thermal anomalies prior to the April 25, 2015 Mw 7.8 Gorkha (Nepal) earthquake are investigated from the Moderate Resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST), air temperature and Outgoing Longwave Radiations (OLR) data. The 2D and 3D wavelet transformation techniques are used to interpret the real time enhancement of the daily MODIS and OLR data before the impending earthquake. Using the wavelet density spectrum, pre-earthquake anomalies in MODIS and OLR are found in connection to the impending earthquake. The spatial images of MODIS and OLR show the evolutionary pattern of the emanation of ions from the epicenter and the surrounding area. The most important feature revealed by the spatial analysis is the eastward migration of temperature clouds due to a strong electric field. The satellite based LST data showed deviation, which crosses the upper bound by 5 °C. All the observations in our case study strongly support the notion of pre-earthquake thermal anomalies. Based on the analysis of the results, it can be concluded that the overabundance of ions from the seismogenic zone is responsible for prompting large temperature perturbations in atmospheric layers.
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