Impact‐Based Thresholds for Investigation of High‐Tide Flooding in the United States

Earth s Future, Journal Year: 2025, Volume and Issue: 13(4)

Published: April 1, 2025

Abstract High‐tide flooding—minor, disruptive coastal inundation—is expected to become more frequent as sea levels rise. However, quantifying just how quickly high‐tide flooding rates are changing, and whether some places experience than others, is challenging. To quantify trends in from tide‐gauge observations, flood thresholds—elevations above which begins—must be specified. Past studies of the United States have used different data sets approaches for specifying thresholds, only directly relate impacts, has lead sometimes conflicting ambiguous results. Here we present a novel method quantifying, with uncertainty, thresholds along coast based on sparsely available impact‐based thresholds. We use those newly modeled make an updated assessment changes across over past few decades. From 1990–2000 2010–2020, almost certainly (probability ) increased East Coast, Gulf California, Pacific Islands, while they very likely decreased Alaska during that time; significant between two decades were not detected Oregon, Washington, Caribbean. Averaging spatially, find probably doubled nationally 2010–2020. Our approach lays foundation future accurately model global coastline.

Language: Английский

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Increases in Sea Level Associated with a Marine Heatwave Drive Tidal Marsh Habitat Shifts

Estuaries and Coasts, Journal Year: 2025, Volume and Issue: 48(4)

Published: April 16, 2025

Abstract Extremechange climate events provide an opportunity to understand how habitats will respond future long-term change. Starting in late 2013, exceptionally strong marine heatwave, or the “Blob”, which was followed by El Niño 2015–2016, resulted anomalous temporary rise sea level on Pacific US coast. We examined response of tidal marsh plant communities three California estuaries spanning over 600 km these elevated water levels. focused seaward ecotone Salicornia pacifica , succulent dominant region. S. cover declined rapidly and sharply at all increased inundation. In areas with Spartina foliosa (Tijuana River Estuary), this low colonized dieback. absence (Carpinteria Salt Marsh Elkhorn Slough), converted mudflat. demonstrate rapid systems transient changes, emphasize value consistent monitoring using field surveys remote sensing for detecting responses rise. These case studies can be used test model predictions, as we empirical evidence vegetative ~ 15 cm sea-level They also offer concrete examples habitat loss type conversion resulting from change, thereby build support adaptation strategies.

Language: Английский

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Exploration and estimation: connecting hydrodynamic responses and hazard potential to coral reef characteristics

Anthropocene Coasts, Journal Year: 2025, Volume and Issue: 8(1)

Published: May 7, 2025

Abstract Coastal areas are one of the most vulnerable regions being subjected to multiple hazards while sheltering people, diverse ecosystems, key infrastructure and other assets. Climate change will produce expected changes drivers affecting these hazardous events which when coupled with uncertainty degree adverse impacts, place coastal communities in intractable circumstances. In limited access human financial resources, like Caribbean Small Island Developing States (SIDS), there must be a focus on practical solutions tools that can support optimal decision-making areas. The adoption nature-based approaches is but solution mitigating potentially deleterious effects, reducing vulnerability enhancing resilience. Through physical modelling, this study explores how selected characteristics synthesized offshore coral reefs affect hydrodynamics nearshore zone seeks formulate quantitative relationships for applications. These serve assessment present-day levels protection offered by provide an insight into future ecosystems conditions, whether caused man or natural influences, hydrodynamics. Assessment potential under different scenarios allow holistic optimization proposed solutions. outputs demonstrated good correlation between wave height after reef above velocities incident width water depths reef. experimental results also trends observed from studies terms attenuation, albeit smaller extent. assessed parameters generally corroborated anticipated patterns although reflection flume appeared skew some output. expressions produced study, though given scope, demonstrate methodology readily augmented improve existing order implement hazard mitigation strategies not only reduce risk assets areas, incorporate systems meaningful way valuable co-benefits communities.

Language: Английский

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Projecting Changes in the Drivers of Compound Flooding in Europe Using CMIP6 Models

Earth s Future, Journal Year: 2024, Volume and Issue: 12(5)

Published: April 30, 2024

Abstract When different flooding drivers co‐occur, they can cause compound floods. Despite the potential impact of flooding, few studies have projected how joint probability may change. Furthermore, existing projections not be very robust, as are based on only 5 to 6 climate model simulations. Here, we use a large ensemble simulations from Coupled Model Intercomparison Project (CMIP6) project changes in extreme storm surges and precipitation at European tide gauges under medium high emissions scenario, enabled by data‐proximate cloud computing statistical surge modeling. We find that will increase northwest decrease most southwest Europe. Averaged over Europe, absolute magnitude these is 36%–49% 2080, depending scenario. The large‐scale similar those wind speeds precipitation, but locally, differences exceed themselves. Due internal variability inter‐model differences, randomly chosen CMIP6 models higher than 10% differ qualitatively all multiple regions, especially scenario earlier twenty‐first century. Therefore, our results provide more robust less uncertain representation for Europe previous projections.

Language: Английский

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Assessing coastal vulnerability to climate change-induced hazards in the Eastern Mediterranean: A comparative review of methodological approaches

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 253 - 278

Published: Jan. 1, 2024

Language: Английский

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How Sea Level Rise May Hit You Through the Backdoor: Changing Extreme Water Levels in Shallow Coastal Lagoons

Geophysical Research Letters, Journal Year: 2023, Volume and Issue: 50(21)

Published: Nov. 8, 2023

Abstract Due to their choked geometry, coastal lagoons can attenuate extreme water levels compared the open sea. However, this protective property is expected decrease due sea‐level rise. By studying idealized in a non‐dimensional parameter space, study describes non‐linear interactions between tides, storm surges, freshwater fluxes into lagoon, and The numbers include lagoon geometry forcing scales. main objective provide an overview of potentially affected highlight importance attenuation changes Tidal surge induced maximum inside rise faster than for most space. Maximum slower strongly lagoons. For compound events, response rising or depends on geometry.

Language: Английский

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The Influence of Future Changes in Tidal Range, Storm Surge, and Mean Sea Level on the Emergence of Chronic Flooding

Earth s Future, Journal Year: 2024, Volume and Issue: 12(2)

Published: Feb. 1, 2024

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 flood frequencies. However, such non‐stationarity tide statistics are largely neglected existing projection methodologies. Here we develop a framework explore the effect different realizations of various sources uncertainty have on projections frequencies, including range storminess. Our methodology captures how observed rates depend surges coincide with extremes. We show higher earlier emergence chronic flooding associated larger rates, lower thresholds, skew magnitudes. Smaller thresholds decreases sea level variability lead commensurately rates. Percentagewise, amplitudes generally much impact frequencies than equivalent percentagewise several implications these findings. Firstly, understanding future local tides required fully quantify hazards. Secondly, hazard assessments may underestimate as not considered. Finally, identifying severities relevant managers imperative useable policy‐relevant for decisionmakers.

Language: Английский

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Wind and rain compound with tides to cause frequent and unexpected coastal floods

EarthArXiv (California Digital Library), Journal Year: 2024, Volume and Issue: unknown

Published: June 12, 2024

With sea-level rise, flooding in coastal communities is now common during the highest high tides. Floods also occur at normal tidal levels when rainfall overcomes stormwater infrastructure that partially submerged by Data describing this type of compound scarce and, therefore, it unclear how often these floods and whether there are other non-tidal factors contribute to flooding. We combine measurements on roads within storm drains with a numerical model examine processes Carolina Beach, NC, USA – community chronically outside extreme storms despite flood mitigation combat Of 43 non-storm we measured year-long study period, one-third were unexpected because forecasted tide was below their monitoring threshold. introduce novel coupling between an ocean-scale hydrodynamic (ADCIRC) community-scale surface water pipe flow (3Di) quantify contributions from multiple drivers. find setup sustained (non-storm) winds modulates extents depth: wind causes deeper, longer, more extensive tides can cause days would not have occurred due alone. Rainfall contributes floods; submerge outfalls daily basis, even minor rainstorms lead as runoff has nowhere drain. As particularly low-lying community, Beach provides glimpse into future challenges worldwide will face predicting, preparing for, adapting increasingly frequent compounding drivers atop rise.

Language: Английский

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Wind and rain compound with tides to cause frequent and unexpected coastal floods

Water Research, Journal Year: 2024, Volume and Issue: 266, P. 122339 - 122339

Published: Aug. 28, 2024

With sea-level rise, flooding in coastal communities is now common during the highest high tides. Floods also occur at normal tidal levels when rainfall overcomes stormwater infrastructure that partially submerged by Data describing this type of compound scarce and, therefore, it unclear how often these floods and extent to which non-tidal factors contribute flooding. We combine measurements on roads within storm drains with a numerical model examine processes Carolina Beach, NC, USA - community chronically outside extreme storms despite flood mitigation combat Of 43 non-storm we measured year-long study period, one-third were unexpected based threshold used for monitoring. introduce novel coupling between an ocean-scale hydrodynamic (ADCIRC) community-scale surface water pipe flow (3Di) quantify contributions from multiple drivers. Accounting compounding effects tides, wind, rain increases up 0.4 m compared simulations include only Setup sustained (non-storm) regional winds causes deeper, longer, more extensive tides can cause days would not have occurred due alone. Rainfall contributes floods; because submerge outfalls daily basis, even minor rainstorms lead as runoff has nowhere drain. As particularly low-lying community, Beach provides glimpse into future challenges worldwide will face predicting, preparing for, adapting increasingly frequent drivers atop rise.

Language: Английский

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Eastern Australian estuaries will transition to tidal flood regimes in coming decades

Cambridge Prisms Coastal Futures, Journal Year: 2024, Volume and Issue: 2

Published: Jan. 1, 2024

Abstract Tidal flooding occurs when coastal water levels exceed impact-based flood thresholds due to tides alone, under average weather conditions. Transitions tidal regimes are already underway for nuisance severities in harbours and bays expected higher coming decades. In the first such regional assessment, we show that same transition tidally forced floods can also be occur Australian estuaries with less than 0.1 m further sea-level rise. Flood historically used only exceeded combined effects of riverine (freshwater) (salt water) influences will then high alone. Once this emerges, it is projected become chronic within two Locations most at-risk emergence subsequent establishment those just inside estuary entrances. These locations exemplified by low freeboard, vertical distance between a threshold typical tide level. We use freeboard-based analysis estimate rise required impacts associated official The resultant tide-only frequency estimates provide lower bound future rates.

Language: Английский

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