Examining Tornado Vulnerability in Kansas with Recent Findings from an EF4 Tornado

Abstract

Tornadoes are one of the most frequently occurring natural hazards in the United States, yet historically they have been understudied in the engineering and social science literature. This first presents the findings from a quick response damage investigation following an EF4 tornado in northeastern Kansas. The nearly 52-km long tornado path damaged hundreds of buildings, but fortunately resulted in no fatalities. That case study was used as motivation to examine tornado vulnerability in Kansas at the county- and urban-area levels through a consideration of the hazard and its intersection with measures of physical and social vulnerability identified in the literature as being correlated with worse outcomes. These hazard and vulnerability factors included the number of tornadoes overall and number of severe tornadoes on record for the geographic area, building code adoption, percentage of housing units that are manufactured homes, percentage of housing units built since 2000, population density, median household income, and percentage high school graduates. These factors were compiled in an additive composite vulnerability score and used to make relative comparisons across the State of Kansas. The tornado vulnerability score identified counties in southwestern Kansas as having the highest vulnerability to tornadoes, whereas counties and urban clusters in northeastern Kansas, where the EF4 tornado addressed herein occurred, may have the lowest vulnerability to tornadoes. It was notable that building code adoption rates differed dramatically between rural and urban areas; only 10 of 105 Kansas counties had adopted a building code as of December 2019, whereas 77 of 78 urban clusters had done so (although several adopted building codes were more than 20 years old). Recommendations are provided for reducing vulnerability to tornadoes, including adopting current building codes, enforcing inspections, and educating citizens about warning communication and shelter locations.