Mapping Heat Vulnerability Index Based on Different Urbanization Levels
in Nebraska, USA
Abstract
Heatwaves cause excess mortality and physiological impacts on humans
throughout the world, and climate change will intensify and increase the
frequency of heat events. Many adaptation and mitigation studies use
spatial distribution of highly vulnerable local populations to inform
heat reduction and response plans. However, most available heat
vulnerability studies focus on urban areas with high heat
intensification by Urban Heat Islands (UHIs). Rural areas encompass
different environmental and socioeconomic issues that require
alternative analyses of vulnerability. We categorized Nebraska census
tracts into four urbanization levels, then conducted factor analyses on
each group and captured different patterns of socioeconomic
vulnerabilities among resulted Heat Vulnerability Indices (HVIs). While
disability is the major component of HVI in two urbanized classes, lower
education and races other than white have higher contributions in HVI
for the two rural classes. To account for environmental vulnerability of
HVI, we considered different land type combinations for each urban class
based on their percentage areas and their differences in heat
intensifications. Our results demonstrate different combination of
initial variables in heat vulnerability among urban classes of Nebraska
and clustering of high and low heat vulnerable areas within the highest
urbanized section. Less urbanized areas show no spatial clustering of
HVI. More studies with separation on urbanization level of residence can
give insights into different socioeconomic vulnerability patterns in
rural and urban areas, while also identifying changes in environmental
variables that better capture heat intensification in rural settings.