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Sea level has been steadily rising over the past century, predominantly due to anthropogenic climate change. The rate of sea level rise will keep increasing with continued global warming, and, even if temperatures are stabilized through the phasing out of greenhouse gas emissions, sea level is still expected to rise for centuries. This will affect coastal areas worldwide, and robust projections are needed to assess mitigation options and guide adaptation measures. Here we combine the equilibrium response of the main sea level rise contributions with their last century's observed contribution to constrain projections of future sea level rise. Our model is calibrated to a set of observations for each contribution, and the observational and climate uncertainties are combined to produce uncertainty ranges for 21st century sea level rise. We project anthropogenic sea level rise of 28–56 cm, 37–77 cm, and 57–131 cm in 2100 for the greenhouse gas concentration scenarios RCP26, RCP45, and RCP85, respectively. Our uncertainty ranges for total sea level rise overlap with the process-based estimates of the Intergovernmental Panel on Climate Change. The "constrained extrapolation" approach generalizes earlier global semiempirical models and may therefore lead to a better understanding of the discrepancies with process-based projections. ; The research leading to these results received funding from the European Union Seventh Framework Programme FP7/2007-2013 under Grant Agreement 603864; the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Germany (11_II_093_Global_A_SIDS and LDCs); and the Austrian Science Fund (FWF): P25362-N26. ; Peer reviewed

Sponsored by the Council on Disaster Risk Management Sea Level Rise and Coastal Infrastructure: Prediction, Risks, and Solutions analyzes the challenges posed by rising sea levels and climate change. Scientists estimate that global sea levels could rise by as much as 20 feet in this century, directly affecting about 100 million people worldwide. Although the problems stemming from higher sea levels are formidable, immediate actions can be identified and executed to lessen the impact of rising waters on coastal infrastructure and communities. Using a risk analysis and management framework, each chapter in this volume focuses on a facet of sea level rise, examining its associated risks and assessing its socioeconomic impact. From this information, appropriate long-term measures and mitigation strategies can be developed. Chapters consider such questions as: How can we model the impact of rising sea levels and increasingly intense tropical storms on coastal infrastructure? What strategies can be phased in to improve new construction? How can existing infrastructure best be targeted for retrofitting? How can risk models be designed to accommodate regional socioeconomic considerations? Engineers, scientists, and policymakers concerned with planning, design, and construction of coastal infrastructure will find this compact assessment useful, relevant, and thought-provoking.

The legal environment for local government in Florida is beginning to change when it comes to sea-level rise (sometimes referred to as SLR). Innovations in institutional structure and governance strategies are underway in the State as well. This paper reviews three recent developments, which relate primarily to comprehensive planning in the State, and explores their implications for Florida's local governments, among others. It begins with the State's decision, in 2011 legislation, to give local governments a new, optional tool – referred to as "Adaptation Action Areas" (AAAs) – to address sea-level rise and related issues in local comprehensive plans. The paper then turns to a second piece of Florida legislation, this one enacted in 2015, which also identifies sea-level rise as a concern but this time mandates that local governments begin to address it and other causes of flood-related risks through their comprehensive planning process. Finally, the paper discusses a third initiative, launched in 2009 by four Southeast Florida counties – Miami-Dade, Broward, Palm Beach, and Monroe – to foster local government and regional coordination on sea-level rise and other climate change issues. This review of these three developments provides a relatively in-depth starting point for understanding key features of the emerging legal and institutional landscape in Florida for addressing sea-level rise, especially with respect to comprehensive planning.

Shoreline habitats and infrastructure are currently being affected by sea level rise (SLR) and impacts will only worsen as global temperatures continue to rise. Decisions made by governments and individuals to adapt to SLR will have profound consequences for coastal ecosystems, transportation systems, and urban settings.Federal guidance for adaptation relies on predictive models to guide planning. This includes planning for the recovery of endangered species in the face of SLR, which is mandated by the federal Endangered Species Act. FHWA and other federal organizations have recognized that new monitoring methods will be needed in order to collect new kinds of data and at a finer scale and wider extent. California among other states, provides extensive step-by-step guidance on how to plan for SLR, including the use of predictive models, and identifies the need for monitoring as well. Despite the recognized need for monitoring methods, no detailed guidance is given at the state level in California or federal level for how to do this.Measurement of sea level has historically been achieved by using tide gauges and global satellite altimetry. There is no consistent method or system for measuring and recording shoreline change over large areas and at fine resolution other than infrequent and expensive LiDAR overflights that do not capture seasonal fluctuations. This policy brief summarizes findings from the project which utilizes a method to monitor shoreline and infrastructure changes in response to SLR using a network of time-lapse cameras.View the NCST Project Webpage

Over the last sixty ears, Singapore has expanded its land footprintover twenty-five percent by reclaiming land from the sea. Its outsized demand for sand to resource these projects has rendered regional sand markets precarious, and successive countries have banned sand exports to Singapore. Nevertheless, the Singapore government has committed to spending $SG one billion (US$ 767 million) a year until 2100 to mitigate sea level rise. While this includes a range of strategies, from improving drainage infrastructure to exploring adaptive solutions, in the main this involves reclaiming vast amounts of land from the sea to act as a bulwark against rising tides. These plans for resilience will be examined through the spectre of Long Island, a proposed project that will act as a barrier against sea level rise and incorporate nature-based solutions that are emblematic of resilience fetishism, all the while obscuring the more foundational element of this resilience, which is sand that will be obtained through granular arbitrage. (Crit Asian Stud/GIGA)

AbstractThis article illustrates the development and functioning of a dynamic spatial model that simulates the effects of gradual sea‐level rise on coastal areas. Emphasis is given to identifying the dynamics of coastal systems and translating them into a spatially explicit dynamic simulation model. The model is designed to be flexible enough to serve as a base model for interdisciplinary research on sea‐level rise and coastal dynamics. An application is provided for a coastal area on Cape Cod, Massachusetts.

The author analyses the relative role of protection (or damage mitigation) expenditures within the total costs associated with raised sea levels induced by climate change. A rule of thumb is derived to approximate the optimal level of protection. Economic efficiency requires that protection expenditures are designed such that the sum of protection costs plus remaining land-loss damage is minimised. The optimal protection level will depend on the relative importance of dryland loss compared with the costs of accelerated wetland loss plus protection expenditures. This framework is then used to estimate the damage-cost functions associated with a sea-level rise for the countries of the OECD.

Abstract. In this paper, a methodology to analyse observed sea level rise (SLR) in the German Bight, the shallow south-eastern part of the North Sea, is presented. The paper focuses on the description of the methods used to generate and analyse mean sea level (MSL) time series. Parametric fitting approaches as well as non-parametric data adaptive filters, such as Singular System Analysis (SSA) are applied. For padding non-stationary sea level time series, an advanced approach named Monte-Carlo autoregressive padding (MCAP) is introduced. This approach allows the specification of uncertainties of the behaviour of smoothed time series near the boundaries. As an example, the paper includes the results from analysing the sea level records of the Cuxhaven tide gauge and the Heligoland tide gauge, both located in the south-eastern North Sea. For comparison, the results from analysing a worldwide sea level reconstruction are also presented. The results for the North Sea point to a weak negative acceleration of SLR since 1844 with a strong positive acceleration at the end of the 19th century, to a period of almost no SLR around the 1970s with subsequent positive acceleration and to high recent rates.

As a result of climate change, many lands are under risk due to the rising sea levels (RSL). Studies show that the mean sea level will likely rise by 0.16 to 0.63 metres before 2050, and 0.2 to 2.5 metres by 2100. Lower-lying islands are more endangered from RSL. One of such islands is Failaka, a small island in Kuwait lying at the entrance of Kuwait Bay, which is located on the north-western side of the Arabian Gulf (Also called the Persian Gulf). Most of Failaka Island is lower than three meters. The Governmental plans are to develop and populate the island. SLR should be considered in such planning. This study focuses particularly on detecting the areas of Failaka Island which are under high threat from the SLR. To detect these areas, spatial analysis of the Digital elevation model (DEM) are used. DEM is estimated for three SLR scenarios (1, 2 and 3 metres). It is expected that 31% of the island will be under sea level height for the SLR of 1 m; 54% for the SLR of 2 metres; and 87% for the SLR of 3 m. Coastal Vulnerability Index (CVI) is estimated as well. The CVI shows that the eastern coast is the most susceptible with regard to the SLR. The model was validated through using ground elevation points (n = 40), and a positive correlation was found with of 0.8019. Geographic Information System (GIS) and Remote sensing (RS) are confirmed to be effective tools for estimating spatial influence of the SLR.

Local projections of future sea-level change are important for understanding climate change risks and informing coastal management decisions. Reliable and relevant coastal risk information is especially important in South Asia, where large populations live in low-lying areas and are at risk from coastal inundation. We present a new set of local sea-level projections for selected tide gauge locations in South Asia. The projections are used to explore the drivers of spatial variations in sea-level change for South Asia over the 21st century under the RCP2.6 and RCP8.5 scenarios. Global sea level rise for 2081-2100 is projected to be 0.39 m (0.26-0.58 m) and 0.65 m (0.47 m-0.93m) for RCP2.6 and RCP8.5 respectively. Local sea-level rise projections for the same period vary spatially over the South Asia region with local sea-level rise in excess of projected global sea level rise in equatorial Indian Ocean but less than projected global sea level rise for northern Arabian Sea and Bay of Bengal. Local sea level rise for 2081-2100 is projected to be 0.44 m (0.29-0.67 m) and 0.72 m (0.51-1.06 m) at Gan II (Maldives) under RCP2.6 and RCP8.5 respectively, whereas for Diamond Harbour (West Bengal) the corresponding changes are 0.32 m (0.19-0.51 m) and 0.57 m (0.39-0.85m). We find that the sterodynamic contribution is generally the leading driver of change at any single location, with future groundwater extraction over the sub-continent landmass the main driver of spatial variations in sea-level across the region. The new localised projections quantify and enhance understanding of future sea-level rise in South Asia, with the potential to feed into decisions for coastal planning by local communities, government, and industry.