Investigation of atmospheric anomalies recorded for moderate or strong earthquakes by geospatial and field data

Abstract

Earthquake science has entered a new era with the development of space-based technologies to measure surface geophysical parameters and deformation at the boundaries of tectonic plates and large faults. Satellite time-series data, coupled with ground based observations where available, can enable scientists to survey pre-earthquake signals in the areas of strong tectonic activity. Cumulative stress energy in seismic active regions under operating tectonic force manifests various earthquakes’ precursors. Space-time anomalies of Earth’s emitted radiation (thermal infrared in spectral range measured from satellite months to weeks before the occurrence of earthquakes, radon in underground water and soil, etc.), and electromagnetic anomalies are considered as pre-seismic signals. This paper presents observations made using time series MODIS Terra/Aqua and NOAA-AVHRR satellite data for derived multi-parameters land surface temperature (LST), outgoing long-wave radiation (OLR), net surface latent heat flux (LHF), mean air temperature (AT), Relative Humidity (RH), and reanalysis data sets for some moderate or strong seismic events recorded in Vrancea region in Romania, which is one of the most active intracontinental seismic areas in Europe. Starting with almost one week prior to a moderate or strong earthquake a transient thermal infrared rise in LST of several Celsius degrees (oC) and the increased OLR values higher than the normal have been recorded around epicentral areas, function of the magnitude and focal depth, which disappeared after the main shock. These observations support seismic LSAIC (Lithosphere – Surfacesphere – Atmosphere -Ionosphere Coupling) Model.