Seismogenic Anomalies in Atmospheric Gravity Waves as Observed from SABER/TIMED Satellite during Large Earthquakes
Subrata Kundu, Swati Chowdhury, Soujan Ghosh, Sudipta Sasmal, Dimitrios Z. Politis, Stelios M. Potirakis, Shih‐Sian Yang, Sandip K. Chakrabarti, Masashi Hayakawa
Abstract
Atmospheric disturbances caused by seismic activity are a complex phenomenon. The Lithosphere–Atmosphere–Ionosphere Coupling (LAIC) mechanism gives a detailed idea to understand these processes to study the possible impacts of a forthcoming earthquake. The atmospheric gravity wave (AGW) is one of the most accurate parameters for explaining such LAIC process, where seismogenic disturbances can be explained in terms of atmospheric waves caused by temperature changes. The key goal of this work is to study the perturbation in the potential energy associated with stratospheric AGW prior to many large earthquakes. We select seven large earthquakes having Richter scale magnitudes greater than seven ( <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" id="M1"> <a:mi>M</a:mi> <a:mo>></a:mo> <a:mn>7.0</a:mn> </a:math> ) in Japan (Tohoku and Kumamoto), Mexico (Chiapas), Nepal, and the Indian Ocean region, to study the intensification of AGW using the atmospheric temperature profile as recorded from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite. We observe a significant enhancement in the potential energy of the AGW ranging from 2 to 22 days prior to different earthquakes. We examine the conditions of geomagnetic disturbances, typhoons, and thunderstorms during our study and eliminate the possible contamination due to these events.