Climate change impacts on flood risk and asset damages within mapped 100-year floodplains of the contiguous United States
A growing body of work suggests that the extreme weather events that drive inland flooding are likely to increase in frequency and magnitude in a warming climate, thus potentially increasing flood damages in the future. We use hydrologic projections based on the Coupled Model Intercomparison Pro...
| Main Authors: | , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2017-12-01
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| Series: | Natural Hazards and Earth System Sciences |
| Online Access: | https://www.nat-hazards-earth-syst-sci.net/17/2199/2017/nhess-17-2199-2017.pdf |
| Summary: | A growing body of work suggests that the extreme weather
events that drive inland flooding are likely to increase in frequency and
magnitude in a warming climate, thus potentially increasing flood damages in
the future. We use hydrologic projections based on the Coupled Model
Intercomparison Project Phase 5 (CMIP5) to estimate changes in the frequency
of modeled 1 % annual exceedance probability (1 % AEP, or 100-year)
flood events at 57 116 stream reaches across the contiguous United States
(CONUS). We link these flood projections to a database of assets within
mapped flood hazard zones to model changes in inland flooding damages
throughout the CONUS over the remainder of the 21st century. Our model
generates early 21st century flood damages that reasonably approximate the
range of historical observations and trajectories of future damages that
vary substantially depending on the greenhouse gas (GHG) emissions pathway.
The difference in modeled flood damages between higher and lower emissions
pathways approaches USD 4 billion per year by 2100 (in undiscounted 2014
dollars), suggesting that aggressive GHG emissions reductions could generate
significant monetary benefits over the long term in terms of reduced flood
damages. Although the downscaled hydrologic data we used have been applied
to flood impacts studies elsewhere, this research expands on earlier work to
quantify changes in flood risk by linking future flood exposure to assets
and damages on a national scale. Our approach relies on a series of
simplifications that could ultimately affect damage estimates (e.g., use of
statistical downscaling, reliance on a nationwide hydrologic model, and
linking damage estimates only to 1 % AEP floods). Although future work is
needed to test the sensitivity of our results to these methodological
choices, our results indicate that monetary damages from inland flooding
could be significantly reduced through substantial GHG mitigation. |
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| ISSN: | 1561-8633 1684-9981 |