Smithsonian Volcano Data on Google Earth

Edward Venzke, Lee Siebert, James F. Luhr

Smithsonian Institution, Global Volcanism Program, NMNH, MRC-119, Washington, DC 20013-7012, United States

Interactive global satellite imagery datasets such as hosted by Google Earth provide a dynamic platform for educational outreach in the Earth Sciences. Users with widely varied backgrounds can easily view geologic features on a global-to-local scale, giving access to educational background on individual geologic features or events such as volcanoes and earthquakes. The Smithsonian Institution’s Global Volcanism Program (GVP) volcano data became available as a Google Earth layer on 11 June 2006.

Locations for about 1550 volcanoes with known or possible Holocene activity are shown as red triangles with associated volcano names that appear when zooming in to a regional-scale view. Clicking on a triangle opens an informational balloon that displays a photo, geographic data, and a brief paragraph summarizing the volcano’s geologic history. The balloon contains links to a larger version of the photo with credits and a caption and to more detailed information on the volcano, including eruption chronologies, from the GVP website. Links to USGS and international volcano observatories or other websites focusing on regional volcanoes are also provided, giving the user ready access to a broad spectrum of volcano data. Updates to the GVP volcano layer will be provided to Google Earth. A downloadable file with the volcanoes organized regionally is also available directly from the GVP website (www.volcano.si.edu) and provides the most current volcano data set.

Limitations of the implied accuracy of spacially plotted data at high zoom levels are also apparent using platforms such as Google Earth. Real and apparent mismatches between plotted locations and the summits of some volcanoes seen in Google Earth satellite imagery occur for reasons including data precision (deg/min vs. deg/min/sec) and the GVP convention of plotting the center-point of large volcanic fields, which often do not correspond to specific volcanic vents. A more fundamental problem originates from the fact that regional topographic mapping does not utilize a standardized global datum, so that locations from topographic maps often diverge from those of the World Geodetic System datum used in geo-registered satellite imagery. These limitations notwithstanding, virtual globe platforms such as Google Earth provide an easily accessible pathway to volcano data for a broad spectrum of users ranging from the home/classroom to Earth scientists.

URL:
http://www.volcano.si.edu/world/globallists.cfm?listpage=googleearth