HR: 16:30h
AN: U22C-03    [PDF]
TI: A Volcano Population Index for Estimating Relative Risk With Example Data From Central America
AU: * Ewert, J W
EM: jwewert@usgs.gov
AF: U.S. Geological Survey Cascades Volcano Observatory, 1300 SE Cardinal Ct., Vancouver, WA 98683
AU: Harpel, C J
EM: charpel@usgs.gov
AF: U.S. Geological Survey Cascades Volcano Observatory, 1300 SE Cardinal Ct., Vancouver, WA 98683
AB: We have developed a Volcano Population Index (VPI) to make objective comparisons among individual volcanoes of populations that may be subject to volcanic hazards. We used volcano location data from the Smithsonian's Global Volcanism Program (GVP) with the LandScan 2001 gridded global population data base from the Oak Ridge National Laboratory to evaluate population distribution near potentially active volcanoes in Central America. The LandScan database reports global ambient population on a 30- by 30-arc second grid (about 1 km by 1 km). The countries in Central America with volcanoes of Holocene age ($<$10 ka) are Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama. The VPI is defined as the sum of the population values of all LandScan 2001 cells within 10 km (VPI$_{10}$) of the coordinates given for each Holocene volcano in the Smithsonian GVP catalog. An analysis of recent evacuations in the region in response to volcanic activity and a global compilation of eruption data by Newhall and Hoblitt (2002) prompted us to also evaluate population within 5 km of Holocene volcanoes and create a 5 km Volcano Population Index (VPI$_{5}$). The VPI5 is an estimate of the number of people who will almost certainly have to be evacuated and cared for over some time period while an eruption is underway. There will almost always be some volcanic phenomena that adversely affects people within 10 km of the vent, and if an eruption is big enough, acute hazards may easily reach 10 km or more in any direction. We view the VPI$_{10}$ as an estimate of the number of people who may have to be evacuated and cared for, and we use the VPI$_{10}$ as the principal population statistic for comparison among individual volcanoes. We calculated the VPI statistics for 75 Central American Holocene volcanoes and report a country by country summary of population within 10 km of Holocene volcanoes that shows the relative exposure to volcano hazards in Central America. We also analyzed the historically-active subset of the Holocene volcanoes. In the region, approximately 4,960,000 persons are located within 10 km of a Holocene-age volcano and of these approximately 2,270,000 persons are within 10 km of an historically active volcano. Fully one third of El Salvador's ambient population, approximately 2.3 million, is within 10 km of a potentially active volcano, and 1,390,000 of these are actually within 10 km of an historically active volcano. Populations in Guatemala and Nicaragua have the next greatest potential exposure to volcano hazards (over 1 million each). All three countries have at least one major urban area within 10 km of a potentially active volcano. Newhall CG, Hoblitt RP (2002) Constructing event trees for volcanic crises. Bull Volcanol 64:3-20
DE: 8419 Eruption monitoring (7280)
DE: 8499 General or miscellaneous
DE: 9360 South America
SC: U
MN: 2003 Fall Meeting