Thermal Anomalies and Earthquakes: Evidence from Wenchuan, China

Earthquake prediction is a difficult problem in Earth sciences. Unsuccessful predictions one after another urged people to explore more synthetic and comprehensive methods for earthquake prediction. The Lithosphere-Atmosphere-Ionosphere (LAI) coupling theory pays great attention to the processes taking place within the near ground layer of atmosphere. It has achieved great results recently, and can enlighten us about the nature of an earthquake's precursor. Based on the NCEP reanalysis dataset, this paper attempts to track the anomalies of the surface's upward long wave radiation flux (ULWRF), the temperature at the depth of 10cm~20cm below ground surface layer (BGL) and the air temperature at 2 meters above ground surface (AIR) around the time of the strong Wenchuan earthquake. Thermal anomalies were observed before and after May 12, 2008, the time of the Wenchuan earthquake. Perhaps the thermal anomaly that occurred prior to the earthquake can be taken as indicators of the earthquake, but in view of the complexity of the earthquake phenomena, using thermal anomaly as a precursor should be done with caution.