Historical Natural Hazards Data in Google Earth

The NOAA National Geophysical Data Center (NGDC), with assistance from the University of Colorado's Cooperative Institute for Research in Environmental Sciences (CIRES), maintains a database of information about historical natural hazards such as earthquakes, tsunamis, and volcanic eruptions. Long-term data from these events can be used to establish the past record of natural hazard event occurrences. These data are also important in disaster recovery, mitigation and response planning for future events. The database includes socioeconomic information (i.e. number of fatalities, injuries, and damage) and scientific data (i.e. earthquake magnitudes, tsunami intensity) for hazard events from ancient times (2000 BC and earlier) to the present. To supplement existing tools for extracting and visualizing the data (web-based forms and ArcIMS interactive maps), the data is now viewable in Google Earth via Keyhole Markup Language (KML). The historical natural hazards database includes several related datasets: significant earthquakes, tsunami source events, tsunami runups (locations where tsunami effects occurred), and significant volcanic eruptions. The related datasets are linked together: for example, the user can display information about a tsunami event that was triggered by a specific earthquake or volcanic eruption. The date range of displayed historical events can be controlled using Google Earth's time slider feature. Tsunami runup locations can be displayed for individual tsunami events or for all events collectively. The tsunami runup placemarks are extruded above the surface of the earth at a height proportional to the maximum wave height recorded at that location, allowing visual comparison of recorded tsunami wave heights. Using Google Earth as a tool for displaying historical natural hazards data enables a broader audience to discover and use the data, with an improved understanding of the geographic and temporal distribution of historical hazard events.