Sea-level Rise Vulnerability Research Articles

Urban Vulnerability Assessment of Sea Level Rise in Singapore through the World Avatar

This paper explores the application of The World Avatar (TWA) dynamic knowledge graph to connect isolated data and assess the impact of rising sea levels in Singapore. Current sea level rise vulnerability assessment tools are often regional, narrow in scope (e.g., economic or cultural aspects only), and are inadequate in representing complex non-geospatial data consistently. We apply TWA to conduct a multi-perspective impact assessment of sea level rise in Singapore, evaluating vulnerable buildings, road networks, land plots, cultural sites, and populations. We introduce OntoSeaLevel, an ontology to describe sea level rise scenarios, and its impact on broader elements defined in other ontologies such as buildings (OntoBuiltEnv ontology), road networks (OpenStreetMap ontology), and land plots (Ontoplot and Ontozoning ontology). We deploy computational agents to synthesise data from government, industry, and other publicly accessible sources, enriching buildings with metadata such as property usage, estimated construction cost, number of floors, and gross floor area. An agent is applied to identify and instantiate the impacted sites using OntoSeaLevel. These sites include vulnerable buildings, land plots, cultural sites, and populations at risk. We showcase these sea level rise vulnerable elements in a unified visualisation, demonstrating TWA’s potential as a planning tool against sea level rise through vulnerability assessment, resource allocation, and integrated spatial planning.

Atoll Mangrove Progradation Patterns: Analysis from Jaluit in the Marshall Islands

AbstractLow-lying islands are vulnerable to coastal erosion, and mangroves, which can mitigate erosion, have suffered enormous losses in recent decades owing to human impacts. Previous studies have little investigated mangrove shores on atolls, which may face combined multiple threats. We analysed the large Marshall Islands atoll of Jaluit, at a higher resolution than previous spatial change studies, finding that mangrove shorelines prograded seawards over the last seven decades. Biogeomorphic colonisation processes were characterised from transects along ~ 14.6 km of shorelines. Mangrove progradation occurred in patterns of arc-shapes evident of long-shore drift deposition, patch expansion of offshore mangrove colonisers, and linear shoreline advance. Significant differences in the rates of expansion were identified, with arc-shaped colonisation showing the fastest rates of expansion. However, linear shoreline advance was the most frequent expansion pattern showing greater than three-fold more classified transects than arc-shaped colonisation and patch expansion. These results have implications for low island mangrove restoration. Applying mangrove planting patterns mimicking these different natural colonisation processes may enhance restoration success in ecosystem-based adaptation projects to mitigate sea level rise vulnerability. Results from this study show that atoll mangrove shorelines demonstrate resilience during past sea level rise rates, and that rates of expansion vary according to patterns of biogeomorphic colonisation.

A Data-Driven Approach for Assessing Sea Level Rise Vulnerability Applied to Puget Sound, Washington State, USA

Sea level rise (SLR) will exert pressures on assets with social value, including things such as infrastructure and habitats, in the coastal zone. Assessing and ranking the vulnerability of those assets can provide insights that support planning and projects that can reduce those vulnerabilities. In this study, we develop a quantitative, data-drive framework for calculating a sea level rise vulnerability score, using publicly available spatial data, for 111,239 parcels in Puget Sound, Washington State, USA. Notably, our approach incorporates an assessment of coastal erosion, as well as coastal flooding, in an evaluation of the exposure of each parcel, and impacts to habitats are quantified alongside impacts to existing infrastructure. The results suggest that sea level rise vulnerability in Puget Sound is widely distributed, but the overall distribution of scores is heavily skewed, suggesting that adaptation actions directed at a relatively small number of parcels could yield significant reductions in vulnerability. The results are also coupled with a concurrently developed social vulnerability index, which provides additional insight regarding those people and places that may be predisposed to adverse impacts from SLR-related hazards. We find that the proposed approach offers advantages in terms of advancing equitable SLR-related risk reduction, but also that the results should be carefully interpreted considering embedded assumptions and data limitations.

Sea level rise vulnerability assessment for State wildlife areas surrounding Humboldt Bay, northern California

Humboldt Bay has the highest rate of sea level rise (SLR) in California (47.2 cm/century). Due to compaction and tectonic subsidence, former tidelands and pastures behind dikes surrounding Humboldt Bay are lower in elevation than bay waters at high tide. Adaptation to future climate change and SLR requires that resource managers understand vulnerability and risk to each wildlife area at a local level, because adaptation to SLR is a risk-based management strategy against an uncertain future requiring site-specific solutions. We conducted a vulnerability assessment of the shoreline of three State wildlife areas surrounding Humboldt Bay: Elk River (ERWA), Fay Slough (FSWA), and Mad River Slough (MRSWA). Breaching of shorelines that border each refuge has the potential to flood a diversity of wetland communities, wildlife habitats, and critical infrastructure within the historic tidal inundation footprint. The total length of diked 1-m shoreline segments potentially impacted by SLR was 6.2 km. The relationship between vulnerability and elevation of diked shoreline segments was significantly correlated for all wildlife areas. Vulnerability of diked shoreline was significantly affected by the type of surface covering. MRSWA had the highest percentage of shoreline fortified with concrete and rock (62.2% [2,876 m]), followed by ERWA (0.3% [2,815 m]). ERWA and FSWA had the greatest percentage of shoreline anchored by vegetation (99.3% [2,834 m] and 91.5% [3,385 m], respectively); FSWA had the highest percentage of unvegetated (i.e., exposed) shoreline (7.4% [252 m]); and ERWA had the highest percentage (86.6% [436 m]) of diked shoreline followed by FSWA (69.2% [633 m]) and MRSWA (33.0% [276 m]). The highest overall ratings of shoreline vulnerability were at ERWA (91.7%), followed by FSSWA (72,4%), and MRSWA (34.4%). Issues related to retention of unique characteristics of each wildlife area, natural resources and species at risk, and adaptive planning for future SLR are discussed.

A NEW FRAMEWORK FOR ACCURACY ASSESSMENT OF LIDAR-DERIVED DIGITAL ELEVATION MODELS

Abstract. Existing approaches to accuracy assessment of LiDAR-derived DEM are typically based on statistical methodology and focus on vertical accuracy. This paper presents a new framework which calls for assessment of not only a DEM’s vertical accuracy, but also its ability to preserve a point’s elevation rank in the bare earth topographic surface. New methods to assess each aspect are presented. For DEM’s vertical accuracy, approximation theory from numerical analysis is used to quantify the total error at each DEM point as well as its three error components – sensor error, ground error, and interpolation error. For DEM’s elevation order which is critical to model terrain structure, the concept of isomorphism in set theory is drawn as the mathematical rationale and Kendall’s rank correlation efficient is used to quantify the accuracy. The new framework is illustrated using a DEM derived from LiDAR for sea-level rise vulnerability assessment of a tidal salt marsh. Compared to conventional methods based on statistics, the new framework and methods produce detailed mapping of error distribution thus enable the identification of the main sources of error and where improvement is needed most. Results call for re-evaluation of the current practice of assessing filtering accuracy in LiDAR data processing and further research on relative elevation and isomorphism.

Relationships between ecosystem properties and sea-level rise vulnerability of tidal wetlands of the U.S. Mid-Atlantic.

Tidal wetlands in the Mid-Atlantic, USA, are experiencing high rates of relative sea level rise, and it is unclear whether they will be resilient in the face of future flooding increases. In a previous study, we found 80% of our study areas in tidal freshwater and salt marshes in the Delaware Estuary and Barnegat Bay had elevation change rates lower than the 19-year increase in mean sea level. Here, we examine relationships between marsh elevation dynamics and abiotic and biotic parameters in order to assess their utility as indicators of vulnerability to relative sea level rise. We further apply a range of marsh vulnerability indicators including elevation change rates to evaluate their ability to corroborate marsh habitat change over the last 30years. Of the field measurements, soil bulk density and belowground plant biomass were among the strongest predictors of elevation change and accretion dynamics across all marsh types and settings. Both tidal freshwater and salt marshes tended to have higher rates of elevation increase and surface accretion in areas where soil bulk density and live belowground biomass were higher. Nine of the ten marshes experienced a net loss of area from the 1970s to 2015 ranging from 0.05 to 14%. Although tidal freshwater marshes were low in elevation and experienced variable elevation change rates, marsh area loss was low. Conversely, salt marshes closest to the coast and perched high in the tidal frame with a higher degree of human modification tended to experience the greatest marsh loss, which incorporated anthropogenic impacts and edge erosion. Thus, our regional assessment points to the need for a comprehensive understanding of factors that influence marsh resilience including human modifications and geomorphic settings.

Elevations of mangrove forests of Pohnpei, Micronesia

Mangrove surface elevation is the crux of mangrove vulnerability to sea level rise. Local topography influences critical periods of tidal inundation that govern distributions of mangrove species and dictates future distributions. This study surveyed ground surface elevations of the extensive mangroves of Pohnpei, Federated States of Micronesia, integrating four survey technologies to solve issues of canopy blocking satellite reception, dense aerial roots limiting line-of-sight, and remoteness from surveyed datums. The island-wide average elevation of the mangrove seaward edge was −0.57 ± 0.13 m relative to MSL, while the landward average elevation was 0.33 ± 0.12 m relative to MSL. The overall mangrove elevation range was thus estimated to be 0.90 m. Mangrove species Bruguiera gymnorrhiza, Rhizophora apiculata and Sonneratia alba had large, overlapping elevation ranges, while Rhizophora stylosa occurred low in the tide frame. These species are likely to be less vulnerable to rising sea level given their greater range of elevation occurrence and presumably flooding tolerance, and hence have the highest adaptive capacity to rising sea level. Some landward edge species had very narrow elevation ranges, increasing their vulnerability to sea-level rise, with adjacent potential upland migration areas limited due to steep topography and human development. Pohnpei mangroves occupied 74% of the mean tidal range, similar to surveys elsewhere in the Pacific. This study demonstrates how more extensive understanding of the elevation distributions of intertidal species can contribute to sea-level rise vulnerability assessments, to allow prioritised climate change adaptation. However, more work is needed in standardizing approaches for global comparisons.

A Conterminous USA-Scale Map of Relative Tidal Marsh Elevation

Tidal wetlands provide myriad ecosystem services across local to global scales. With their uncertain vulnerability or resilience to rising sea levels, there is a need for mapping flooding drivers and vulnerability proxies for these ecosystems at a national scale. However, tidal wetlands in the conterminous USA are diverse with differing elevation gradients, and tidal amplitudes, making broad geographic comparisons difficult. To address this, a national-scale map of relative tidal elevation (Z*MHW), a physical metric that normalizes elevation to tidal amplitude at mean high water (MHW), was constructed for the first time at 30 × 30-m resolution spanning the conterminous USA. Contrary to two study hypotheses, watershed-level median Z*MHW and its variability generally increased from north to south as a function of tidal amplitude and relative sea-level rise. These trends were also observed in a reanalysis of ground elevation data from the Pacific Coast by Janousek et al. (Estuaries and Coasts 42 (1): 85–98, 2019). Supporting a third hypothesis, propagated uncertainty in Z*MHW increased from north to south as light detection and ranging (LiDAR) errors had an outsized effect under narrowing tidal amplitudes. The drivers of Z*MHW and its variability are difficult to determine because several potential causal variables are correlated with latitude, but future studies could investigate highest astronomical tide and diurnal high tide inequality as drivers of median Z*MHW and Z*MHW variability, respectively. Watersheds of the Gulf Coast often had propagated Z*MHW uncertainty greater than the tidal amplitude itself emphasizing the diminished practicality of applying Z*MHW as a flooding proxy to microtidal wetlands. Future studies could focus on validating and improving these physical map products and using them for synoptic modeling of tidal wetland carbon dynamics and sea-level rise vulnerability analyses.

Coral reef islands can accrete vertically in response to sea level rise.

Increased flooding due to sea level rise (SLR) is expected to render reef islands, defined as sandy or gravel islands on top of coral reef platforms, uninhabitable within decades. Such projections generally assume that reef islands are geologically inert landforms unable to adjust morphologically. We present numerical modeling results that show reef islands composed of gravel material are morphodynamically resilient landforms that evolve under SLR by accreting to maintain positive freeboard while retreating lagoonward. Such island adjustment is driven by wave overtopping processes transferring sediment from the beachface to the island surface. Our results indicate that such natural adaptation of reef islands may provide an alternative future trajectory that can potentially support near-term habitability on some islands, albeit with additional management challenges. Full characterization of SLR vulnerability at a given reef island should combine morphodynamic models with assessments of climate-related impacts on freshwater supplies, carbonate sediment supply, and future wave regimes.

Summer Seasonal Sea-level Rise and Associated Potential Storm Surge Vulnerability of the West Coast of Korea

Kim, H.-J. and Suh, S.-W., 2019. Summer seasonal sea-level rise and associated potential storm surge vulnerability of the West Coast of Korea. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 21-25. Coconut Creek (Florida), ISSN 0749-0208.Typhoon-induced storm surge usually occurs during the summer season. Thus, it is important to account for seasonal sea-level (SL) rise in coastal hazard mitigation. In this study, we analyzed one hour intervals of tidal records for Incheon (INC), Kunsan (KUN), and Mokpo (MOK) stations, located on the West Coast of Korea (WCK), as well as atmospheric pressure, to determine the correlation of SL fluctuations as they relate to the inverse barometer effect. Results exhibited annual (summer) sea-level rise (SLR) of 0.35 (0.32), 0.39 (0.39), and 0.55 (0.53) cm/year at the three stations, respectively. However, the mean SL (MSL) during the summer season was approximately 20 cm higher than the annual MSL. It was found that seasonal atmospheric pressure highly affected SL, with 1.58–1.73 cm per hPa owing to the inverse barometer effect; however, there were phase lags in the summer of one month or more. Although the nodal factor accounted for ± 3.7% of the M2 tidal amplitude over 18.6-year return period, the resulting M2 amplitude was maximized in 2090 at 2.87 m, 2.14 m, and 1.62 m at the three reference stations, owing to the macro-tidal environment of the WCK than in 2100. Thus, the target year associated with global warming and SLR, which is normally 2100, should be shifted one decade prior to ensure effective coastal storm surge vulnerability hazards analyses.

Evaluating sea-level rise vulnerability assessments in the USA

Many coastal communities around the world are increasingly faced with pressure from sea level rise (SLR). Adapting to the impacts of SLR is now considered inevitable. Many coastal communities in the USA have started to invest in vulnerability assessments that seek to identify the degree of future risk induced by SLR and key vulnerable sectors as well as to provide a sound factual basis for designing and implementing adaptations. However, no study has systematically analyzed the content of these emerging assessments and their quality. This study aims to address this gap by evaluating 64 SLR vulnerability assessments in the USA using an established multi-criteria evaluation framework and by identifying governance factors that affect assessment quality. This study is the first baseline study to understand how the vulnerability of SLR has been assessed by US governments and, more importantly, shed light on pathways for their future improvement. Our analysis finds that the content and quality of the existing assessments vary widely. One-sided assessments that only consider physical exposure are common, and most assessments do not include plans for adaptations. The wealth of the area, amount of funding, mainstreaming efforts, and public awareness are all positively correlated with the assessment quality. We also find that assessments primarily authored by planning staff are lower in quality than those conducted through collaboration. Our findings offer comparative, empirical knowledge for urban planners and coastal managers to improve future vulnerability assessments and adaptation planning for SLR.

An Evaluation of Sea Level Rise Vulnerability and Resilience Strategy to Climate Change in the Coastline of Bangladesh

An Evaluation of Sea Level Rise Vulnerability and Resilience Strategy to Climate Change in the Coastline of Bangladesh

Housing investment, sea level rise, and climate change beliefs

We investigate the association of new housing construction with sea level rise exposure and climate change beliefs. We combine U.S. Census construction permits data, sea level rise projections, county-level climate change belief estimates (Howe et al., 2015), and standard housing controls. The results suggest that (i) sea level rise vulnerability is associated with significantly reduced construction in areas with high climate change beliefs, but that (ii) this relationship is significantly attenuated in more skeptical areas, suggesting that climate skepticism may be delaying adaptation.

Assessing the sea-level rise vulnerability in coastal communities: A case study in the Tampa Bay Region, US

Sea-level rise (SLR) has drawn unprecedented attention from coastal communities around the world. In fact, many are already being affected and, in response, SLR vulnerability assessments have increasingly emerged in the US as the local communities' first attempt on the adaptation planning agenda. However, to date, little is known about these early planning endeavors in terms of how vulnerability is conceptualized and operationalized. By reviewing the current local SLR vulnerability assessments in the US, we find that most are only focusing on their biophysical exposure to SLR overlooking other important vulnerability factors including sensitivity and adaptive capacity. The limited number of SLR scenarios and the lack of consideration for extreme events are also considered as the major deficiencies. To fill these gaps, we propose a conceptual vulnerability assessment framework to operationalize the full concept of vulnerability and test it through a case study in the Tampa Bay region, Florida. By comparing the vulnerability results of the common practice with our proposed framework, we find large variances in the resulting findings stressing the importance of selecting the proper assessment approach. This paper finally concludes with urban planning and governance implications and future research directions. Coastal planner and managers wanting to improve their understanding of the communities' vulnerability to SLR will benefit from this study.

Sea-Level Rise Vulnerability Assessment of Bicycle and Trail Networks

AbstractTransportation infrastructure continues to be at risk to climate change impacts including sea-level rise (SLR) inundation. Past studies have primarily focused on motorized facilities; howev...

Modeling multiple sea level rise stresses reveals up to twice the land at risk compared to strictly passive flooding methods

Planning community resilience to sea level rise (SLR) requires information about where, when, and how SLR hazards will impact the coastal zone. We augment passive flood mapping (the so-called “bathtub” approach) by simulating physical processes posing recurrent threats to coastal infrastructure, communities, and ecosystems in Hawai‘i (including tidally-forced direct marine and groundwater flooding, seasonal wave inundation, and chronic coastal erosion). We find that the “bathtub” approach, alone, ignores 35–54 percent of the total land area exposed to one or more of these hazards, depending on location and SLR scenario. We conclude that modeling dynamic processes, including waves and erosion, is essential to robust SLR vulnerability assessment. Results also indicate that as sea level rises, coastal lands are exposed to higher flood depths and water velocities. The prevalence of low-lying coastal plains leads to a rapid increase in land exposure to hazards when sea level exceeds a critical elevation of ~0.3 or 0.6 m, depending on location. At ~1 m of SLR, land that is roughly seven times the total modern beach area is exposed to one or more hazards. Projected increases in extent, magnitude, and rate of persistent SLR impacts suggest an urgency to engage in long-term planning immediately.

Satellite remote sensing to monitor mangrove forest resilience and resistance to sea level rise

Abstract Coastal ecosystems, such as mangroves, provide key ecosystem services for climate change mitigation and adaptation. However, combined anthropogenic activities and climatic change‐driven sea level rise (SLR) pose a severe threat to their global persistence, and to the continued delivery of these services. Mangrove vulnerability to SLR depends upon capacity for both resilience (landward migration) and resistance (maintained functioning with the existing distribution), which are in turn hindered by extractive activities and coastal infrastructure development. Limited landscape‐scale data availability means existing SLR vulnerability assessment frameworks lack rigorous quantification of these discrete processes. Here we develop and implement a novel multi‐product (multispectral, microwave, derived‐product) open‐access satellite remote sensing approach to assess both coastal ecosystem SLR resilience and resistance capacity in multiple mangrove sites across the world, and landscape‐level and anthropogenic factors driving these capacities. Our approach allows comparative ranking of resilience and resistance capacities across sites, based on relative observed ecosystem change (biomass, distribution) and in constraints to these two components of SLR vulnerability. We observe mostly low SLR resilience and resistance across our case study sites. Furthermore, we find that site‐specific resilience and resistance capacities and constraints can be highly incongruent, highlighting the importance of comprehensive SLR vulnerability monitoring for effective management. High within‐site variation was also detected in resilience and resistance capacities and their constraints. This underlines the importance of spatially explicit monitoring at extensive spatial scales to inform decision making. The methodology developed and repeat‐pass imagery employed adds to the remote monitoring and assessment toolkit for adaptive coastal ecosystem management under SLR, providing a new approach to inform conservation and management priority assessments in data‐deficient regions.

ELEVATION-BASED SEA-LEVEL RISE VULNERABILITY ASSESSMENT OF MINDANAO, PHILIPPINES: ARE FREELY-AVAILABLE 30-M DEMS GOOD ENOUGH?

Abstract. We assessed the vertical accuracies and uncertainties of three freely-available global DEMs as inputs to elevation-based sea-level rise vulnerability assessment of Mindanao, Philippines – an area where above average SLR of 14.7 mm/year was recently found. These DEMs are the Shuttle Radar Topography Mission (SRTM) DEM, ASTER Global DEM (GDEM Version 2), and ALOS World 3D-30 (AW3D30). Using 2,076 ground control points, we computed each DEM’s vertical accuracies and uncertainties, and from these we determined the smallest increment of sea-level rise (SLRImin) that should be considered when using the DEMs for SLR impact assessment, as well as the Minimum Planning Timeline (TLmin) for an elevation-based SLR assessment. Results of vertical accuracy assessment revealed Root Mean Square Errors of 9.80 m for ASTER GDEM V2, 5.16 m for SRTM DEM, and 4.32 m for AW3D30. Vertical uncertainties in terms of the Linear Error at 95 % Confidence (LE95) were found to be as follows: 19.21 m for ASTER GDEM V2, 10.12 m for SRTM DEM, and 8.47 m for AW3D30. From these, we found that ASTER GDEM2 is suitable to model SLR increments of at least 38.41 m and it will take 2,613 years for the cumulative water level increase of 14.7 mm/year to reach the minimum SLR increment afforded by this DEM. For the SRTM DEM, SLRImin and TLmin were computed as 20.24 m and 1,377 years, respectively. For the AW3D30, SLRImin and TLmin were computed as 16.92 m and 1,151 years, respectively. These results suggest that the readily available global DEMs' suitability for mapping coastal inundations due to SLR in our study area is limited by their low vertical accuracies and high uncertainties. All the three DEMs do not have the necessary accuracy and minimum uncertainties that will make them suitable for mapping inundations of Mindanao at smaller increments of SLR (e.g., SLR ≤ 5 m). Hence, users who apply any of these DEMs for SLR impact assessment at SLRIs lower than the DEM’s SLRImin must be cautious in reporting the areas of SLR vulnerable zones. Reporting the inundated areas as a range instead of a singular value for a given SLR scenario can highlight the inherent accuracy and uncertainty of the DEM used in the assessment.

Evolution of Two Urbanized Estuaries: Environmental Change, Legal Framework, and Implications for Sea-Level Rise Vulnerability

The San Francisco Bay (CA, USA) and the Tagus Estuary (Lisbon, Portugal) share striking similarities in terms of morphology and urban development. A finer analysis of development patterns reveals crucial differences in the extent of shoreline alteration and types of land use that now encroach upon natural estuarine habitat. Through historical map analysis and prior stratigraphic and historical research, we reconstruct in GIS environment the evolution of both estuaries over the last millennia and the relative distribution of different classes of land cover. We also discuss the legal frameworks that accompanied this evolution, and how they have influenced the process of wetland reclamation and landfilling. We compared the legal history and synchronous patterns of development by compiling historical mapping information and resorting to GIS analysis to explore spatial patterns over time. This method was useful in isolating events and decisions that were unique to each of the case studies. The Tagus Estuary has experienced disruption of natural environments for over two millennia. Yet, the State has been able to keep estuarine lowlands under public control, even if vast areas have been transformed into farmland. Public control could allow wetland migration with rising seas and restoration efforts. The San Francisco Bay was affected by several decades of elevated sediment loads in the 19th century, which induced rapid wetland expansion, but virtual cutoff of sediment supply by dams in the 20th century now impairs their ability to accrete. Meanwhile, tidal wetlands were subject to extremely fast and poorly regulated development. Artificially filled and/or drained wetlands were transferred to local governments and private landowners, in violation of the Public Trust Doctrine. The transformation of wetlands into salt ponds, industrial zones and even residential neighborhoods created extensive developed areas at or below sea level, which are vulnerable to even modest rises in sea level. Remaining wetlands are now heavily encroached on their landward side by urban development, which prevents their landward migration. Different legal interpretations of comparable definitions of public trusts and jurisdictions over shorelines may have significant implications for the ability to adapt to sea-level rise.

Modeling sea-level rise vulnerability of coastal environments using ranked management concerns

Coastal erosion, salt-water intrusion, and flooding due to sea-level rise threaten to degrade critical coastal strand and wetland habitats. Because habitat loss is a measure of the risk of extinction, managers are keen for guidance to reduce risk posed by sea-level rise. Building upon standard inundation mapping techniques and suitability mapping, we develop a ranking system that models sea-level rise vulnerability as a function of six input parameters defined by wetland experts: type of inundation, time of inundation, soil type, habitat value, infrastructure, and coastal erosion. We apply this model under the mid-century and end-of-century RCP8.5 sea-level projection (0.30 m by 2057, and 0.74 m by 2100) according to the Intergovernmental Panel on Climate Change Fifth Assessment Report. To demonstrate this method, the model is applied to three coastal wetlands on the Hawaiian islands of Maui and O‘ahu. Each ranked input parameter is mapped upon a 2 m horizontal resolution raster and final vulnerability is obtained by calculating the weighted geometric mean of the input vulnerability scores. Areas that ranked with the ‘highest’ vulnerability should be the focus of future management efforts. The tools developed in this study can be a guide to prioritize conservation actions at flooded areas and initiate decisions to adaptively manage sea-level rise impacts.