Sarah Okeson of the Peoria, Ill., Journal Star mapped tornado sirens and looked at how much of the county they cover, as well as geocoding the county's schools and nursing homes and looking for gaps in the coverage. "The National Weather Service thinks Peoria is adequately prepared for a tornado or other disaster." Okeson describes in a NICAR-L posting that "I went to all 80 of the county's tornado sirens with a GPS device and then put the locations on my computer and converted them to a shapefile. I drew buffers around the sirens and calculated how many people in the county weren't covered by comparing the siren coverage area to the census blocks."
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