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Abstract Sea‐level rise is leading to increasingly frequent coastal floods globally. Recent research shows that changes in tidal properties and storm surge magnitudes can further exacerbate sea‐level rise‐related increases in flood frequencies. However, such non‐stationarity in tide and storm surge statistics are largely neglected in existing coastal flood projection methodologies. Here we develop a framework to explore the effect that different realizations of various sources of uncertainty have on projections of coastal flood frequencies, including changes in tidal range and storminess. Our projection methodology captures how observed flood rates depend on how storm surges coincide with tidal extremes. We show that higher flood rates and earlier emergence of chronic flooding are associated with larger sea‐level rise rates, lower flood thresholds, and increases in tidal range and skew surge magnitudes. Smaller sea‐level rise rates, higher flood thresholds and decreases in sea level variability lead to commensurately lower flood rates. Percentagewise, changes in tidal amplitudes generally have a much larger impact on flood frequencies than equivalent percentagewise changes in storm surge magnitudes. We explore several implications of these findings. Firstly, understanding future local changes in storm surges and tides is required to fully quantify future flood hazards. Secondly, existing hazard assessments may underestimate future flood rates as changes in tides are not considered. Finally, identifying the flood frequencies and severities relevant to local coastal managers is imperative to develop useable and policy‐relevant projections for decisionmakers.
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From 2d to 3d: Flood Risk Communication Via Dynamic, Isometric Street Views
There is increasing evidence that climate change will lead to greater and more frequent extreme weather events, thus underscoring the importance of effectively communicating risks of record storm surges in coastal communities. This article reviews why risk communication often fails to convey the nature and risk of storm surge among the public and highlights the limitations of conventional (two-dimensional) storm surge flood maps. The research explores the potential of dynamic street-level, augmented scenes to increase the tangibility of these risks and foster a greater sense of agency among the public. The study focused on Sunset Park, a coastal community in southwest Brooklyn that is vulnerable to storm surges and flooding. Two different representations of flooding corresponding to a category three hurricane scenario were prepared: (1) a conventional two-dimensional flood map (“2D” control group) and (2) a, dynamic, street view simulation (“3D”test group). The street view simulations were found to be (1) more effective in conveying the magnitude of flooding and evacuation challenges, (2) easier to use for judging flood water depth (even without a flood depth legend), (3) capable of generating stronger emotional responses, and (4) perceived as more authoritative in nature
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- Award ID(s):
- 1826134
- PAR ID:
- 10576381
- Publisher / Repository:
- SSRN
- Date Published:
- Subject(s) / Keyword(s):
- flood risk communication mapping augmented reality community survey
- Format(s):
- Medium: X
- Institution:
- SSRN
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Posted Content:
- https://doi.org/10.2139/ssrn.4950754
