Surface wave magnitude processing is triggered by the automatic locations. The present seismic processing system uses Pentium III PCs with the Windows 2000 operating system. Two identical PC systems are active for redundancy, plus for the added ability to process multiple aftershocks that are common with tsunamigenic earthquakes. A fourth backup is also available for interactive locations and message generation. The seismic processing PCs use a four-monitor card which displays information on four separate monitors.
Options are available for transferring data between monitors and for message generation.
Once an earthquake's parameters are determined, the GIS displays its location on both a global and smaller local map which are on separate monitors. The global map supports overlays of historical seismicity, tsunamis, plate boundaries, major cities, seismometers, tide gages, recent earthquakes, modeling results, and tsunami travel time contours. The localized map also supports many overlays, such as, cities, earthquakes ranked by magnitude and depth, roads, topography, pipelines, power lines, tide gages, seismometers, airports, railroads, place names, and tsunamis. Regional warnings are issued within 15 minutes of earthquake origin time and are based solely on seismic data. These warnings are based on seismic data, along with historical tsunami records and recorded tsunami amplitudes from tide gages.