Sea Level Rise Research Articles

Senses of justice after managed retreat in New York city

Sea level rise and increasing frequency and intensity of coastal storms are driving the need for managed retreat and relocation for at risk coastal populations. Managed retreat through voluntary buyouts is typically studied either from the perspective of the buyouts’ process or focused on those who leave, but little attention is given to who and what is left behind. How do buyouts impact those staying behind, and their senses of justice? We examine this question for the low-lying majority-minority neighborhood of Edgemere, Queens in New York City where Superstorm Sandy buyouts and a long history of failed urban renewal have led to large amounts of vacant land. This study analyzes ongoing and intersectional conditi ons of residents’ flood vulnerability. It grounds this analysis in 18 in-depth interviews with local residents capturing their perceptions of vacant land and its reuse, flood risk and neighborhood needs. The analysis is complemented with field observations, semi-structured interviews with city agencies involved in resilience planning initiatives and analysis of historical urban planning and open space plans in this area. Findings reveal the importance of elevating residents’ understanding of place to inform possible land uses after retreat in historically disinvested neighborhoods. Furthermore, they reveal both the injustices of and attachments to living in flood prone, disenfranchised coastal neighborhoods. They also show how these experiences entangle with the citywide housing crisis. In conclusion, if retreat and post-buyout efforts aspire to be just, they need to center how past and present contextual injustice shapes the relationships between distributive and recognitional injustice.

Past and Future Storm-Driven Changes to a Dynamic Sandy Barrier System: Outer Cape Cod, Massachusetts

Sandy barrier systems are highly dynamic, with the most significant natural morphological changes to these systems occurring during high-energy storm conditions. These systems provide a range of economic and ecosystem benefits and protect inland areas from flooding and storm impacts, but the persistence of many coastal barriers is threatened by storms and sea-level rise (SLR). This study employed observations and modeling to examine recent and potential future influences of storms on a sandy coastal barrier system in Nauset Beach, MA. Drone-derived imagery and digital elevation models (DEMs) of the study area collected throughout the 2023–2024 winter revealed significant alongshore variability in the geomorphic response to storms. Severe, highly localized erosion (i.e., an erosional “hotspot”) occurred immediately south of the Nauset Bay spit as the result of a group of storms in December and January. Modeling results demonstrated that the location of the hotspot was largely controlled by the location of a break in a nearshore sandbar system, which induced larger waves and stronger currents that affected the foreshore, backshore and dune. Additionally, model simulations of the December and January storms assuming 0.3 m (1 ft) of SLR showed the system to be relatively resistant to major geomorphic changes in response to an isolated storm event, but more susceptible to significant overwash and breaching in response to consecutive storms. This research suggests that both very strong isolated storm events and sequential moderate storms pose an enhanced risk of major overwash, breaching, and possibly inlet formation today and into the future, raising concern for adjacent communities and resource managers.

The Sea Level Rise under Global Warming

Global warming is the biggest environmental issue facing humanity in the 21st century, and the resulting sea level rise (SLR) is a major disaster that humans need to confront. According to predictions, even in the most optimistic scenario, global temperatures will still rise by 0.3-1.7 before 2100, and sea levels will continue to rise by at least 2.3 meters within the next 2000 years. Even though many regions are currently experiencing severe SLR and many countries have implemented corresponding strategies, there is little can be done for small and underdeveloped countries. This study summarizes the current situation and predictions of SLR through a literature review, and compiles various hazards caused by SLR, as well as how different countries in different regions are responding to it, and proposes opinions on how to deal with SLR. It can be used as a reference for readers who want to understand SLR, its hazards, and how to deal with it, so that readers can have a clear understanding of the relevant knowledge about SLR.

Mechanisms and Modeling of Sea Level Rise in the Context of Global Warming

Sea level rise due to global warming is an important topic in current climate change research. In this study, we explore how complex natural processes triggered by global warming drive sea level change by analyzing climate models. We focus on the main drivers of sea level rise, including ice sheet melting and ocean thermal expansion. In addition, the article discusses in detail how positive feedback mechanisms and negative feedback mechanisms work together to influence the climate change process. In order to predict the future trend of sea level rise, this article models and simulates the global temperature, glacier changes and ocean dynamics based on the General Circulation Model (GCM). Although the model has some uncertainties, especially in cloud feedback and data completeness, it still provides a valuable predictive tool for understanding future sea level changes. The conclusions of this study point to the possibility of accelerated sea level rise as global temperatures continue to rise, with wide-ranging and far-reaching impacts on coastal ecosystems and human societies around the globe.

Estimating ocean heat content from the ocean thermal expansion parameters using satellite data

Abstract. Ocean heat content (OHC) is a depth-integrated physical oceanographic variable used to precisely measure ocean warming. Because of the limitations associated with in situ conductivity, temperature, and depth (CTD) data as well as ocean reanalysis system products, satellite-based approaches have gained importance in estimating the daily to decadal variability of OHC over the vast oceanic region. Efforts to minimize the biases in satellite-based OHC estimates are needed to realize the actual response of the ocean to the brunt of climate change. In the current study, an attempt has been made to better implement the satellite-based ocean thermal expansion method to estimate OHC at 17 depth extents ranging from the surface to 700 m. To achieve this objective, artificial neural network (ANN) models were developed to derive thermosteric sea level (TSL) from a given dataset of sea surface temperature, sea surface salinity, geographical coordinates, and climatological TSL. The model-derived TSL data were further used to estimate OHC changes based on the thermal expansion efficiency of heat. Statistical analysis showed high correlation coefficients and low errors in the validation of model-derived TSL and OHC for the 700 m modeling depth (N 388 469, R 0.9926 and 0.9922, RMSE 1.16 m and 1.56 GJ m−2, MBE −0.19 m and −0.24 GJ m−2, MBPE −0.46 % and −0.03 %, MAE 0.76 m and 1.03 GJ m−2, and MAPE 2.34 % and 0.13 %) and nearly similar results at the remaining modeling depths. These results suggest that the proposed ANN models are capable of generating satellite-based daily OHC maps by covering both shallower and deeper oceanic regions of varying bathymetry levels (≥20 m). In addition, the first-ever attempt to estimate the ocean thermal expansion component (i.e., TSL) from satellite data was successful, and the model-derived TSL can be used to obtain high-end sea level rise products in the global ocean.

Preserving History: Assessments and Climate Adaptations at the House of the Seven Gables in Salem, Massachusetts, USA

Salem, Massachusetts, is one of the oldest cities in the United States (1629) and its coastal location on the Atlantic helped create one of the wealthiest cities in America during the late 18th century, but today its coastal location threatens many of its buildings due to sea level rise and increased storm activity. The House of the Seven Gables, a National Historic Landmark District, consists of five important historic buildings, the most famous being The Turner Ingersoll Mansion (1668), more commonly known as The House of the Seven Gables. Considered one of the most important houses in America, it is also one of the most threatened historic buildings due to its location on Salem’s harbor. The House of the Seven Gables conducted a two-year study funded by Massachusetts Coastal Zone Management to evaluate the risks posed by climate change. This process included the use of data from groundwater monitoring wells and a tidal gauge installed on-site, along with soil samples and a detailed survey base plan including topography and subsurface infrastructure. The project team then used the Massachusetts Coastal Flood Risk Model (MC-FRM) to assess climate change impacts on the site in 2030, 2050, and 2070, and then created a plan for adaptations that should be implemented before those risks materialize. Strategies for adapting to storm surges, increasing groundwater, and intense surface water runoff were evaluated for their effectiveness and appropriateness for the historic site. The conclusion of the study resulted in a five-phase plan ending in the managed retreat of the historic buildings to higher ground on the existing site. This article goes beyond other research that suggests coastal retreats by demonstrating how to quantitatively evaluate current and future coastal issues with predictive models and how to set viable dates for adaptive solutions and a managed retreat.

Modeling the Impact of Greenland Ice Sheet Melting on Global Sea Level Elevation and Climate Change Feedback Mechanisms

The rapid acceleration of global warming is leading to an increased rate of glacier melt at the Earth's poles, which exacerbates the threats posed by the climate crisis and contributes to rising ocean levels. The Greenland Ice Sheet, recognized as the second-largest ice sheet globally, has housed its extensive glaciers and ice caps for at least 18 million years [1]. The melting and potential collapse of this ice sheet could significantly affect Worldwide climate and sea height. This research aims to develop a coupled model to assess rising sea levels caused by the thawing of the Greenland Ice Sheet, incorporating factors such as global warming, glacier volume, hydrothermal expansion, isostatic rebound, ice dynamics, changes in the gravitational field, and the absorption and release of methane gas. Additionally, the paper investigates the hazards connected to melting glaciers exacerbating global warming. This research provides a crucial foundation for forecasting the long-term impacts of the Greenland Ice Sheet's melting on global climate change.

Reconstructing the Environmental Conditions in the Prehistoric Coastal Landscape of SE Lemnos Island (Greece) Since the Late Glacial

Agia Bay is located on the southeastern coast of Lemnos Island. The coastal area today is characterized by aeolian sandy deposits (dunes). The systematic investigation of a 15.5-m long sediment core from the coastal plain of Agia Bay aimed to shed light to the paleoenvironmental evolution of the area that prehistoric groups occupied. The exhaustive study of the faunal and floral remains of the deposits including benthic foraminifera, ostracods, mollusks, pollen, and dinoflagellate cysts as well as plant remains was further supported by sedimentological, micromorphological, and elemental analyses, magnetic susceptibility measurements, ERT, and absolute dating. Four main evolutionary stages have been identified since the Late Glacial. At the base of the sequence, the fluvial activity dominated the sedimentation in the area forming a small shallow wetland, while after 12,500 cal BP, a marine signal was observed at the wetland. At 7500 cal BP, the wetland increased in size and depth, whereas at 6000 up to 4000 cal BP, a connection of the wetland to the sea was established, and an inner lagoon formed. After 4000 cal BP, a nearshore environment developed due to the sea-level rise. Pollen assemblages record the occurrence of a mixed deciduous oak forest in the island interior around 6000 cal BP, while after 5000 cal BP, an expansion of Mediterranean vegetation, shaped by human activity, is inferred.

Bottom-up perspectives on “climate adaptation” from “vulnerable” coastal communities: a political ecology perspective from Taiwan

ABSTRACT The global climate crisis severely affects coastal communities worldwide. Not only do coastal communities have to cope with the effects of the climate crisis, such as sea-level rise, increased flooding, changing weather patterns, droughts and increased salinisation, they also have to cope with other non-climate related shocks and stresses. Many studies often focus on the “climate adaptation” processes of these “vulnerable” communities in linear and cause-and-effects ways. This study approaches the concept of climate adaptation and vulnerability from a political ecology perspective in the context of coastal Taiwan – a region heavily affected by climate change. Through in-depth interviews, this study argues that households have developed various strategies to adapt not only to environmental changes (e.g. increased cold spells and flooding) but also to top-down flood hazard mitigation planning and infrastructure, changing demographics, and encroaching solar panel companies (for the “greater good of the nation”). Furthermore, decisions made in the past have a direct impact today, such as land subsidence due to the massive shift towards aquaculture several decades ago. These factors showcase how adaptation and vulnerability are relational concepts being coshaped by both structural determinants, such as political economy and power relations, and micro-level factors, such as personal aspirations and people’s life courses.

Root productivity contributes to carbon storage and surface elevation adjustments in coastal wetlands

Abstract Background and aims Organic matter additions in coastal wetlands contribute to blue carbon sequestration and adjustment to sea-level rise through vertical substrate growth, with accurate modelling of these dynamics requiring information of root mass and volume additions across tidal gradients. This study aims to characterise the influence of vegetation zonation and tidal position on root mass and volume dynamics within substrates. Methods The root ingrowth technique was coupled with sediment cores to quantify below-ground root mass and volume production, standing stocks and turnover across two years to 90 cm depth at Kooweerup, Victoria, Australia. Results We indicate a complex non-linear relationship between fine root mass production and tidal position, influenced by variable vegetation structures across mangrove (442–3427 g m−2 yr−1), saltmarsh (540–860 g m−2 yr−1) and supratidal forest (599 g m−2 yr−1) zones. Fine root volume additions ranged from 274 to 4055 cm3 m−2 yr−1 across sampling locations. Root production was greatest for older mangroves and tidally defined optimal zones of production were evident for mangrove and saltmarsh. Live roots extended deeper than typically studied, reaching depths of 1.0 m in forested zones. Conclusion This information of root mass and volume additions across wetland live rooting zones can be used to improve highly parameterised models accounting for carbon sequestration and substrate vertical adjustment along intertidal gradients. We recommend that future studies measure root production across the entire active rooting zone or to 1 m depth to align with standard carbon accounting measurement depths.

Compound coastal flooding in San Francisco Bay under climate change

The risk of compound coastal flooding in the San Francisco Bay Area is increasing due to climate change yet remains relatively underexplored. Using a novel hybrid statistical-dynamical downscaling approach, this study investigates the impacts of climate change induced sea-level rise and higher river discharge on the magnitude and frequency of flooding events as well as the relative importance of various forcing drivers to compound flooding within the Bay. Results reveal that rare occurrences of flooding under the present-day climate are projected to occur once every few hundred years under climate change with relatively low sea-level rise (0.5 m) but would become annual events under climate change with high sea-level rise (1.0 to 1.5 m). Results also show that extreme water levels that are presently dominated by tides will be dominated by sea-level rise in most locations of the Bay in the future. The dominance of river discharge to the non-tidal and non-sea-level rise driven water level signal in the North Bay is expected to extend ~15 km further seaward under extreme climate change. These findings are critical for informing climate adaptation and coastal resilience planning in San Francisco Bay.

Controls on coastal saline groundwater across North America

Abstract Groundwater is crucial to sustaining coastal freshwater needs. About 32 million people in the coastal USA rely on groundwater as their primary water source. With rapidly growing coastal communities and increasing demands for fresh groundwater, understanding controls of continental-scale coastal groundwater salinity is critical. To investigate what hydrogeological factors (e.g., topography, hydraulic conductivity) control coastal saline groundwater at continental scales, we have simulated variable-density groundwater flow across North America with the newly developed Global Gradient-based Groundwater Model with variable Densities (G3M-D). The simulation results suggest that under a steady climate and pre-development conditions (i.e., steady 30-year mean groundwater recharge, no withdrawals nor sea level rise) saline groundwater is present in 18.6% of North America's coastal zone, defined as up to 100 km inland and up to 100 m above mean sea level. We find that the coastal zone is particularly vulnerable to containing saline groundwater at low hydraulic gradients (<10-4) and large hydraulic conductivities (>10-2 m day-1). To analyze model parameter sensitivities, i.e., which parameters control the resulting distribution of saline groundwater, we utilize the inherent spatial model variability. We find that hydraulic gradient, topographic gradient, hydraulic conductivity, and aquifer depth are important controls in different places. However, no factor controls coastal groundwater salinization alone, suggesting that parameter interactions are important. Using G³M-D based on G3M, a model that previous work found to be strongly controlled by topography, we find no controlling influence of recharge variability on the saline groundwater distribution in North America. Despite a likely overestimation of saline interface movement, the model required 492 000 years to reach a near-steady state, indicating that the saline groundwater distribution in North America has likely been evolving since before the end of the last ice age, approximately 20 000 years ago.

In What Ways Might Physical Tipping Points in the Climate System Pose Security Problems Now and in the Future?

This paper analyzes physical tipping points in the climate system and their implications for national security, food security and social stability. Physical tipping points are critical states in the climate system that, once passed, lead to irreversible, rapid, and self-accelerating changes. Major tipping points include melting glaciers and rising sea levels, the collapse of terrestrial ecosystems, and an increase in the frequency and intensity of climate extremes. The paper explores the far-reaching impact of these tipping points on security issues, proposes countermeasures and policy recommendations by analyzing the case of Arctic climate change on Russian security, and emphasizes the importance of interdisciplinary cooperation and policy responses to reduce the risks posed by climate change.

Paleolimnology and Natural Versus Anthropogenic Influx During the Late Holocene from Vembanad Wetland, Ramsar Site, Kerala, India

A multi-proxy study of diatoms, palynofacies, and grain size was conducted on a 100 cm core from Arookutty, Vembanad wetland, Kerala, India, to reconstruct paleolimnological changes during the late Holocene, with a focus on natural versus anthropogenic influences. Four distinct depositional phases, from ca. 500 BCE to ca. 400 CE, were identified, aligning with the Roman Warm Period (RWP). The period from ca. 500 BCE to ca. 450 BCE shows high freshwater and marine planktic diatoms, augmented by silicoflagellates and terrestrial organic matter, with a low dinocyst presence, suggesting a dynamic aquatic environment. The period from ca. 450 BCE to ca. 350 BCE is marked by a high sand content, indicating significant runoff and terrestrial influx, along with increased freshwater and marine planktic diatoms and evidence of human activity in the area. Similarly, the period from ca. 350 BCE to ca. 50 CE is characterized by high sand content and strong anthropogenic influences, with a rise in silicoflagellates, pointing to rising sea levels and high monsoonal precipitation. The period from ca. 50 CE to ca. 400 CE initially shows a decrease in sand and an increase in mud, reflecting a weakening southwest monsoon, likely due to solar variations. However, from ca. 300 CE to ca. 400 CE, sand content rises again, accompanied by high terrestrial influx and dinocysts, while silicoflagellates diminish completely. Thus, despite the dominance of the RWP, the coastal region experienced an extended period of reduced monsoonal activity for a particular span.

Linear-viscous flow of temperate ice.

Accurately modeling the deformation of temperate glacier ice, which is at its pressure-melting temperature and contains liquid water at grain boundaries, is essential for predicting ice sheet discharge to the ocean and associated sea-level rise. Central to such modeling is Glen's flow law, in which strain rate depends on stress raised to a power of n = 3 to 4. In sharp contrast to this nonlinearity, we found by conducting large-scale, shear-deformation experiments that temperate ice is linear-viscous (n ≈ 1.0) over common ranges of liquid water content and stress expected near glacier beds and in ice-stream margins. This linearity is likely caused by diffusive pressure melting and refreezing at grain boundaries and could help to stabilize modeled responses of ice sheets to shrinkage-induced stress increases.

Assessing blue carbon in mangrove ecosystems of Seychelles.

Mangrove forests play an important role in climate change mitigation and adaptation, globally recognized as natural climate solution. The protection and restoration of mangrove ecosystems are especially important to Small Island Developing States, like Seychelles, due to their vulnerability to the impacts of climate change, such as sea level rise and tropical cyclones. Therefore, it is crucial for countries like Seychelles to develop baseline information on the status of their mangrove forests to guide conservation and management actions. In this study, we conducted a field campaign to collect local data on plant (i.e., aboveground and belowground) and soil carbon from representative mangrove forests in the inner and outer islands of Seychelles. We used this data to develop, for the first time, a blue carbon assessment for Seychelles' mangrove ecosystems. Seychelles holds 2195ha of mangrove forests, with ∼80% of them found on the outer island of Aldabra Atoll. Seychelles mangrove ecosystems store 688,091±18,353 tonnes of organic carbon (or 2.5 million tonnes CO2e) and an average of 477.0±16.2 tonnes of carbon per hectare, with 70% of their total carbon stocks stored in their soils. Aldabra Atoll holds the highest total carbon stocks, accounting for 67% of Seychelles' mangrove stocks, despite having a relatively shallow soil organic layer (∼40cm) due to the dominance of limestone and 'coral champignon' below 40cm depth. Seychelles currently protects ∼85% of its mangrove extent including the Aldabra Atoll, a UNESCO World Heritage and Ramsar site, and Port Launay, a Ramsar site. Overall, field data from this study demonstrates the important climate mitigation potential of Seychelles' mangrove forests and the important role they play in supporting Seychelles in achieving its Nationally Determined Contributions (NDCs) commitments.

Multifidelity uncertainty quantification for ice sheet simulations

Ice sheet simulations suffer from vast parametric uncertainties, such as the basal sliding boundary condition or geothermal heat flux. Quantifying the resulting uncertainties in predictions is of utmost importance to support judicious decision-making, but high-fidelity simulations are too expensive to embed within uncertainty quantification (UQ) computations. UQ methods typically employ Monte Carlo simulation to estimate statistics of interest, which requires hundreds (or more) of ice sheet simulations. Cheaper low-fidelity models are readily available (e.g., approximated physics, coarser meshes), but replacing the high-fidelity model with a lower fidelity surrogate introduces bias, which means that UQ results generated with a low-fidelity model cannot be rigorously trusted. Multifidelity UQ retains the high-fidelity model but expands the estimator to shift computations to low-fidelity models, while still guaranteeing an unbiased estimate. Through this exploitation of multiple models, multifidelity estimators guarantee a target accuracy at reduced computational cost. This paper presents a comprehensive multifidelity UQ framework for ice sheet simulations. We present three multifidelity UQ approaches—Multifidelity Monte Carlo, Multilevel Monte Carlo, and the Best Linear Unbiased Estimator—that enable tractable UQ for continental-scale ice sheet simulations. We demonstrate the techniques on a model of the Greenland ice sheet to estimate the 2015-2050 ice mass loss, verify their estimates through comparison with Monte Carlo simulations, and give a comparative performance analysis. For a target accuracy equivalent to 1 mm sea level rise contribution at 95 % confidence, the multifidelity estimators achieve computational speedups of two orders of magnitude.

Climate change and the planned relocation of people: A longitudinal analysis of Vunidogoloa, Fiji.

Rising sea levels under a changing climate will cause permanent inundation, flooding, coastal erosion, and saltwater intrusion. An emerging adaptation response is planned relocation, a directed process of relocating people, assets, and infrastructure to safer locations. Climate-related planned relocation is an unfolding process, yet no longitudinal studies have examined outcomes over time. Vunidogoloa, a low-lying coastal village in Fiji, relocated to higher land in 2014. This paper considers the dynamic outcomes of relocation, based on qualitative data collected between 2015 and 2023. It examines: residents' changing experience of climate and environmental risk; governance and decision-making processes over time; improved access to many resources and services along with incomplete infrastructure; opportunities and threats to health; and changing social organization and place-based values. The paper foregrounds change over time and provides in-depth examination of dynamic planned relocation experiences and (mal)adaptation outcomes in Vunidogoloa, Fiji.

A Systematic Review Of Blue Carbon Potential in Coastal Marshlands: Opportunities For Climate Change Mitigation And Ecosystem Resilience

This systematic review evaluates the blue carbon potential of coastal marshlands, emphasizing their role in climate change mitigation, ecosystem service provision, and economic value within climate finance mechanisms. Drawing on a comprehensive analysis of 198 peer-reviewed articles, this study synthesizes findings on the carbon sequestration dynamics of coastal marshlands, their contributions to biodiversity support, and their capacity to enhance coastal resilience through flood protection and water quality improvement. The review highlights the threats posed by land-use changes, urbanization, and climate change impacts such as sea-level rise and saltwater intrusion, which collectively undermine the ecological integrity and service delivery of these critical ecosystems. It further explores the integration of coastal marshlands into climate finance mechanisms, demonstrating their viability as natural assets within carbon markets and payment for ecosystem services schemes, with restoration projects yielding returns of $7 to $15 for every dollar invested. Despite these advancements, significant knowledge gaps remain, particularly in the standardization of methodologies for quantifying carbon dynamics and the socio-economic benefits of conservation, which limit the scalability of these efforts. By addressing these challenges, this study underscores the necessity of interdisciplinary approaches, robust policy frameworks, and sustained research to maximize the potential of coastal marshlands as a cornerstone of nature-based solutions for climate mitigation and sustainable development.

The mental health impact of climate change on Pacific Islanders: A systematic review focused on sea level rise and extreme weather events

Objective This systematic review investigates the impact of climate change on the mental health of Pacific Island Nations (PINs), with a focus on identifying culturally tailored interventions and appropriate research methodologies to address these impacts. Method A systematic review of peer-reviewed literature up to May 18, 2024, was conducted using the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocol and the Population, Interest Area, and Context (PICo) framework. Empirical studies on the impact of climate change on mental health in PINs were evaluated by using the Quality Assessment Tool for Studies with Diverse Designs (QATSDD). Results Six studies from the Solomon Islands, Cook Islands, and Tuvalu were identified, indicating significant mental health impacts from sea level rise (SLR) and extreme weather events with compounding and mitigating effects across diverse groups. The Skills for Life Adjustment and Resilience (SOLAR) program was highlighted as a promising culturally adapted intervention. Conclusion Climate change significantly impacts mental health, particularly in PIN communities facing SLR and Extreme Weather Events (EWE). Culturally sensitive interventions, local knowledge, and further research are vital to mitigate these effects and support well-being.