Evaluating Multiparameter Response to Seismic Thermal Anomalies From Global Major Earthquakes

Abstract

Thermal anomalies (TAs) associated with earthquake activity have been widely studied by analyzing various satellite thermal infrared datasets. However, there is a significant lack of research on key response parameters. In the present work, based on M≥7.0 earthquakes worldwide from 2007 to 2022, we evaluate multiple parameters for the detection of seismic TAs by analyzing the significant sequence of TAs and the defined performance indicators. We considered seven thermal-related parameters, including skin temperature, surface latent heat flux, surface net thermal radiation (STR), and 2 m temperature (T2m) from ERA5; clear-sky outgoing longwave radiation (ClrOLR) and outgoing longwave radiation from AIRS and NOAA (AIRS-OLR and NOAA-OLR). The classification evaluation was conducted based on focal mechanisms (normal fault, thrust fault, and strike-slip fault) and earthquake locations (continental and oceanic earthquake). Our results show that ClrOLR and T2m have remarkable effectiveness in detecting seismic TAs. From the perspective of focal mechanism, T2m performs best for the earthquakes triggered by normal faults and also good for thrust fault events, and ClrOLR is most effective for those triggered by strike-slip faults. In terms of location, ClrOLR preforms best for continental earthquakes, while T2m is most effective for oceanic earthquakes. By conducting a comparative analysis using a synthetic earthquake catalog and modifying the nonseismic time window, we have demonstrated that our results are robust. Our results provide valuable information for the application of thermal-related parameters in earthquake prediction.