Natural Hazards, Disasters, and Demographic Change: The Case of Severe Tornadoes in the United States, 1980–2010

Abstract

Natural hazards and disasters distress populations and inflict damage on the built environment, but existing studies yielded mixed results regarding their lasting demographic implications. I leverage variation across three decades of block group exposure to an exogenous and acute natural hazard—severe tornadoes—to focus conceptually on social vulnerability and to empirically assess local net demographic change. Using matching techniques and a difference-in-difference estimator, I find that severe tornadoes result in no net change in local population size but lead to compositional changes, whereby affected neighborhoods become more White and socioeconomically advantaged. Moderation models show that the effects are exacerbated for wealthier communities and that a federal disaster declaration does not mitigate the effects. I interpret the empirical findings as evidence of a displacement process by which economically disadvantaged residents are forcibly mobile, and economically advantaged and White locals rebuild rather than relocate. To make sense of demographic change after natural hazards, I advance an unequal replacement of social vulnerability framework that considers hazard attributes, geographic scale, and impacted local context. I conclude that the natural environment is consequential for the sociospatial organization of communities and that a disaster declaration has little impact on mitigating this driver of neighborhood inequality.

Using Disaster Outcomes to Validate Components of Social Vulnerability to Floods: Flood Deaths and Property Damage across the USA

“…Our results indicate that the influences of poverty-race interactions associated with greater property losses extend beyond Hurricane Katrina, and could be a generalizable phenomenon across the contiguous US, validated by empirical data for over 11,000 riverine events. Other studies of quantitative hazard outcomes have also found significant race interactions; populations census blocks with tornado events in the US from 1980 to 2010 across 25 states became more White and had lower rates of poverty post-hazard, suggesting out-migration by poor and non-White populations [64]. The high propensity for flood-related property loss in poor communities of color could be due to increased flood exposure (due to limited housing choices and more accessible housing in floodplains), poor housing quality, structural racism (e.g., systematic underinvestment in flood mitigation structures such as levees), or institutional racism and bias (e.g., low flood insurance coverage (7%) in Native American communities, because FEMA was not mapping them, a prerequisite for the National Flood Insurance Program [103]).…”

“…Death and property damage were chosen as the outcomes for analysis because of data availability for every county, allowing us to examine salient social vulnerability factors generalizable to the continental US. Outcomes of flood events related to social vulnerability not covered in this paper include agricultural damage, ability to invest in future agricultural adaptation [63], out-migration, rate of return, ability to rebuild [64,65], property buyouts, health impacts not related to morality [15], and psychological impacts (see Rufat et al [58] for a review of these and other outcomes). We focus our review more on empirical US case studies, the study area for this paper.…”

“…For example, in Hurricane Katrina, only low income African-American populations had lower rates of returning and rebuilding, but not African-American populations in general [94]. Studies on tornado damage have found that US census blocks become significantly less poor and more White post-disaster, suggesting poor and minoritized populations may not be able to recover in place, and so migrate [64].…”

Migration as a Vector of Economic Losses from Disaster-Affected Areas in the United States

“…To generalize the previous statement, as a vector of economic losses from disasteraffected areas, migration stands to reshuffle the spatial distribution of economic resources across places and thereby reshape the landscape of spatial inequality Elliott 2018, 2019;Logan et al 2016;Raker 2020;Smiley et al 2018). However, several recent papers on migration in response to extreme weather disasters and to climate and environmental change more broadly suggest that this redistribution takes place within existing-largely local and regional-networks of migration flows (Curtis et al 2015;DeWaard et al 2016;Hauer 2017).…”

Risky Development: Increasing Exposure to Natural Hazards in the United States

“…Economically advantaged residents typically prefer to repair or rebuild structures affected by extreme winds rather than relocate. In contrast, socioeconomically vulnerable populations are forcibly mobile, even when disaster declarations and federal aid are in effect (Raker, 2020). 2,000,000 3,000,000 4,000,000 During the last eight decades, structures in tornado hotspots were built at a similar rate as across CONUS (Figures 1b and 5b).…”