This paper presents a preliminary analysis of thermal anomalies before the Baja California M7.2 earthquake
occurred on April 4, 2010. The results show that surface air temperature of the Mexicali station, which is the
closest one to the epicenter, reaches its maximum value on March 30, which is also the maximum value from
January 1 to April 10, 2010. Weather stations far away from the epicenter (100 km away) show no other thermal
anomaly. In particular, the National Centers for Environmental Prediction Final Operational Global Analysis
(NCEP-FNL) air temperature data show a maximum temperature change between March 30 and 31 at the epicenter
grid point, while the other surrounding 7199 grid points show medium to low temperature change. The
microwave brightness temperature measured by the Advanced Microwave Scanning Radiometer on board the
EOS Aqua satellite (AMSR-E) also shows an increase on March 31. The results of multiple thermal parameters
analysis obey well the DTS criterions: deviation (D), time synchronism (T), and space consistency (S), so they
can be considered as convincing seismic thermal anomalies. This analysis might contribute to make reliable
earthquake predictions.
Keywords: Earthquake anomaly