HR: 10:50h
AN: S42B-03    [Abstracts]
TI: Geosynchronous Weather Satellite Nightly TIR Cooling Curves and Earthquakes
AU: * Bryant, N
EM: Nevin.A.Bryant@jpl.nasa.gov
AF: JPL/Caltech, 4800 Oak Grove Dr., Pasadena, CA 91109-8099, United States
AU: Zobrist, A
EM: Albert.L.Zobrist@jpl.nasa.gov
AU: Logan, T
EM: Thomas.L.Logan@jpl.nasa.gov
AU: Fretz, R
EM: Richard.K.Fretz@jpl.nasa.gov
AU: Bamberry, R
EM: Raymond.J.Bamberry@jpl.nasa.gov
AB: Thermal anomalies prior to earthquakes have been a controversial topic for some time. Previous investigations of three earthquake events by the authors showed thermal changes, and as a result a more systematic analysis of over fifteen events, representing a range of magnitudes and epicenter depths was undertaken. Earthquakes associated with plate movement (strike-slip and thrust faulting), rather than volcanism, were to be considered. It was the purpose of this study to determine if thermal anomalies could be found in association with known earthquakes by systematically co-registering geosynchronous weather satellite images at the sub-pixel level and then determining if statistically significant responses had occurred prior to an event. The automatic co- registration procedures used for this task to accommodate all properties particular to weather satellite observations taken at night. The technique relies on the general condition where ground cools after sunset. The technique applies best to the use of the geosynchronous weather satellites (GOES,and Meteosat), where images are taken every thirty minutes. Use of the geosynchronous satellites also reduces the potential for miscalculation of trends due to weather front movement or local cloud/fog formation. The data analyzed for each earthquake includes 10 days prior to each event and 5 days after the event as well as the day of the event. The data are for every half hour from sunset to dawn, thermal IR bands. We also obtained the same Julian dates of the data for the three previous years to use as a baseline. The data sets were used to systematically measure the observance of thermal anomalies in two key contexts. First is the degree any thermal anomaly just prior to an event can be demonstrated to deviate from a baseline thermal profile of nightly cooling derived from the previous three years and recorded weather history. Second is the possibility to compare the earthquake epicenter with nearby regions having similar or different geology using the same imagery but no history of seismic activity. This experimental design has helped address questions regarding the "uniqueness" of thermal anomalies observed by us and others previously, and help characterize the observed thermal responses under a variety of magnitude, depth, and geologic conditions.
DE: 0694 Instruments and techniques
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
DE: 8123 Dynamics: seismotectonics
SC: Seismology [S]
MN: 2007 Fall Meeting