Abstract. Megacities are predominantlyconcentrated along coastlines, making them exposed to a diverse mix ofnatural hazards. The assessment of climatic hazard risk to cities rarely hascaptured the multiple interactions that occur in complex urban systems. Wepresent an improved method for urban multi-hazard risk assessment. We thenanalyze the risk of New York City as a case study to apply enhanced methodsfor multi-hazard risk assessment given the history of exposure to multipletypes of natural hazards which overlap spatially and, in some cases,temporally in this coastal megacity. Our aim is to identify hotspots ofmulti-hazard risk to support the prioritization of adaptation strategies thatcan address multiple sources of risk to urban residents. We usedsocioeconomic indicators to assess vulnerabilities and risks to threeclimate-related hazards (i.e., heat waves, inland flooding and coastal flooding) at high spatial resolution.The analysis incorporates local experts' opinions to identify sources ofmulti-hazard risk and to weight indicators used in the multi-hazard riskassessment. Results demonstrate the application of multi-hazard riskassessment to a coastal megacity and show that spatial hotspots ofmulti-hazard risk affect similar local residential communities along thecoastlines. Analyses suggest that New York City should prioritize adaptationin coastal zones and consider possible synergies and/or trade-offs tomaximize impacts of adaptation and resilience interventions in the spatiallyoverlapping areas at risk of impacts from multiple hazards.
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 conterminous United States (CONUS), we identified earthquake, flood, hurricane, tornado, and wildfire hazard hotspots, and overlaid them with land use information from the Historical Settlement Data Compilation data set. Our results show that 57% of structures (homes, schools, hospitals, office buildings, etc.) are located in hazard hotspots, which represent only a third of CONUS area, and ∼1.5 million buildings lie in hotspots for two or more hazards. These critical levels of exposure are the legacy of decades of sustained growth 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 considered.
more » « less- Award ID(s):
- 1924670
- NSF-PAR ID:
- 10360660
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Earth's Future
- Volume:
- 9
- Issue:
- 7
- ISSN:
- 2328-4277
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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