ES-03. Risky development: Increasing exposure to natural hazards in the United States

Abstract
Losses from natural hazards are escalating dramatically, with more properties and critical infrastructure affected each year. Although the magnitude, intensity and/or frequency of certain hazards has increased, development contributes to this unsustainable trend, as disasters emerge when natural disturbances meet vulnerable assets and populations. To diagnose development patterns leading to increased exposure in the United States, we identified earthquake, wildfire, flood, hurricane, and tornado hazard hotspots, and overlaid them with land-use information from the Historical Settlement Data Compilation dataset. Our results show that 57% of structures are located in hazard hotspots, which represent only a third of U.S. area, and ~1.5 million homes lie in hotspots for two or more hazards. These critical levels of exposure are the legacy of decades of sustained development, and point to our inability, lack of knowledge, or unwillingness to limit development in hazardous zones. Development in these areas is still growing more rapidly than the baseline rates for the nation, portending larger future losses even if the effects of climate change are not contemplated. 1 Earth Lab, Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado, Boulder, Colorado 2 Department of Geography, University of Colorado, Boulder, Colorado 3 Human‐Environment Systems, Boise State University, Boise, Idaho *Corresponding author: Virginia Iglesias (virginia.iglesias@colorado.edu)