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LandScan |
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Natural disasters and nuclear, biological,
and chemical (NBC) releases place vast populations at risk, often with
little or no advance warning. Consider the following examples: An industrial
plant releases hazardous chemicals into the atmosphere, as Union Carbide's
plant did in Bhopal, India in 1984. A nuclear power plant releases radiation,
as Chernobyl did in 1986. Toxic gases spread from a terrorist's bomb,
as sarin did in Tokyo, Japan in 1994. These examples represent global
threats to local places. Emergency response by the United Nations, the
United States, and other national and international organizations requires
simulation of contaminant transport by air and water plus improved estimates
of global population distribution. Geographic information is essential
for quick and effective response. How will the contaminant be dispersed?
Where will it go? How many people are at risk? Who are they? Where are
they? Air diffusion models available today are capable of estimating
contaminant plumes at spatial resolutions far exceeding those of the
official censuses available for most countries. For many years, the
U.S. Census Bureau has enhanced the precision of global population estimates
through a manual procedure designed to allocate rural populations to
20' X 30' cells and urban populations to circles centered on major population
concentrations. Yet, analysis of most hazardous releases requires data
resolutions on the order of 1 square kilometer or even finer. To meet
this need, Oak Ridge National Laboratory (ORNL) developed an automated
procedure to allocate rural and urban population distributions to 30"
X 30" (arc view) cells. The resulting population distribution can be
used for (a) emergency response to natural disasters, terrorist incidents,
or industrial accidents; (b) humanitarian relief in famines and other
long term disasters; (c) estimation of populations affected by global
sea level rise; and (d) numerous other environmental and demographic
applications.
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