Coastal erosion and sea level rise: Implications for ocean beach and San Francisco's westside transport project

Abstract

One of the consequences of sea level rise resulting from the greenhouse effect is increased coastal erosion. This article discusses a model of erosion that can be used to estimate the response of beaches to sea level rise. The model is applied to Ocean Beach, California, with particular attention to the consequences of accelerated erosion for the San Francisco Westside Sewer Transport. Results obtained show that erosion produced by accelerated sea level rise could cause substantial damage to the structure. Large expenditures on beach nourishment will be required to protect the transport and the recreational value of the beach.     

Land use implications of sea level rise: A case study at myrtle beach,South Carolina

Abstract

the prospect of global warming and consequent sea level rise will have important implications for coastal communities. this article examines the land use implications of alternate sea level rise scenarios on the city of myrtle beach, south carolina. current trends as well as high and low sea level rise scenarios are superimposed on the city's beach profile and near shore contours to estimate the type and value of land development likely to be impacted.

It is found that losses associated with accelerated sea level rise would be particularly high in the city's hotel district and that overall property loss could range from 21 to 60% of the city's total property value. to lessen these potential losses, coastal communities such as myrtle beach must choose among one of three policy options including: (1) barricade the beach, (2) raise the land, and (3) implement a strategic retreat. specific alternatives within each of these options are explored in turn. the article concludes that successful development plans will incorporate ground rules sensitive to and consistent with dynamic coastal processes.     

Response of coastal zone management programs to sea level rise in the United States

Abstract

State coastal zone management programs are responding to the potential impacts of accelerated sea level rise through a wide range of activities and policies. This article provides a brief overview of the Coastal Zone Management Act and other federal laws that provide the basis for coastal state regulatory activities. It surveys the level of response to sea level rise by state coastal management programs in 24 marines coastal states, from formal recognition to implementation of policies addressing the issue. Individual state CZMP responses and policies that have been implemented or proposed are categorized. The adaptation of sea level rise to ongoing institutional objectives is discussed and policy constraints and trends are summarized.     

Socio-ecological Mobility: A Research Strategy for a New Coastline

Abstract

Persistent development, population pressures, and increasing natural hazards are unequivocally changing socio-ecological systems in the coastal zone. This essay provides direction and initiates scientific dialog on the potential role of mobility in adapting to natural and social changes in coastal environments. The essay identifies four key research areas on information needed to develop coastal management actions and policies that support and recognize socio-ecological coupling in coastal areas. The proposed research includes: (1) modeling localized scenarios that illustrate the tradeoffs associated with various sea level rise adaptation, (2) assessing and consolidating mobility terminology for different applications and contexts, (3) developing solutions to synchronize the co-migration of natural environments and built infrastructure, and (4) evaluating existing or creating new transparent, equitable, and sustainable policies and incentives to support socio-ecological mobility by using case studies and social science methods to understand how people make mobility decisions in different contexts.     

State vs. national interests in an expanded territorial sea

Abstract

The recently adopted Law of the Sea (LOS) Convention contains a provision allowing coastal nations to adopt 12‐mile territorial seas. Already 104 nations (of a total of 137 coastal nations) have claimed territorial seas of 12 miles or wider. The paper discusses the factors which, in the opinion of the authors, could cause the United States to broaden its territorial sea from the present 3 miles to 12 miles within the next half‐dozen years or so. The state‐federal ocean use and resource management issues that will be raised by such a move are reviewed and options for dealing with the jurisdictional issues are developed. Given the political and economic volatility of these issues and their complexity, the use of a broadly representative and well‐staffed study commission to formulate a course of action is suggested.     

Opportunities for a state‐federal partnership in an expanded territorial sea

Abstract

The United States currently has a 3‐mile territorial sea limit which is under the jurisdiction of coastal states. In the event the United States joins with other countries in adopting a 12‐mile territorial sea, Congress may consider extending state jurisdiction to 12 miles. It may be in the best interest of coastal states to oppose extension and instead support a strengthened federal‐state ocean management regime which disregards boundary lines and is based on the sharing of outer continental shelf leasing revenues along with a guaranteed role for coastal states in federal decision‐making.     

GIS-Based Coastal Behavior Modeling and Simulation of Potential Land and Property Loss: Implications of Sea-Level Rise at Collaroy/Narrabeen Beach,Sydney (Australia)

Rising sea level potentially poses a threat to many coastal areas, thereby possibly affecting coastal environments, including human assets. Taking into account the precau--tionary principle demanded at the Framework Convention for Climate Change in Rio de Janeiro in 1992, coastal managers and planners are required to evaluate the possibility of both physical and economic impacts of sea-level rise. However, long-term and cost-intensive data capture is often not affordable for a first estimation of general trends. To determine physical and economic impacts on a spatial scale of less than 10 km, a rapid and low-cost method is required. A Geographic Information System (GIS), in combination with readily available data and two coastal behaviour models (the Bruun-GIS Model and the Aggradation Model) was applied to simulate shoreline recession caused by a rise in sea level. In addition, the potential impacts of a 50-year design storm were considered in conjunction with sea-level rise. The monetary vulnerability was assessed and combined with the simulated recession rates. This procedure provides a first estimate on the potential risk a locality (here Collaroy/Narrabeen Beach) may face due to the impacts of sea-level rise and/or coastal storms. Overall, the modelling outcome suggests that long-term erosion problems associated with rising sea level are less significant in comparison with those impacts associated with short-term coastal storm events for Collaroy/Narrabeen Beach.     

The cost of not holding back the sea: Toward a national sample of economic vulnerability

Abstract

National and regional estimates of U.S. economic vulnerability to greenhouse‐induced sea‐level rise are produced from a sample of 30 discrete regions scattered evenly along the coastline. Scenarios that envision 50 cm, 100 cm, and 200 cm of greenhouse‐induced sea‐level rise are considered. They can be expected to place $39.2, $65.6, and $133.3 billion, respectively, (1989 dollars) of existing development in jeopardy through 2050, and $133.3, $308.7, and $909.4 billion through 2100. Sampling error and consideration of the uncertainty with which we currently view future greenhouse‐induced sea‐level rise places the 25th and 75th percentile values of expected cumulative vulnerability at $38.5 and $76.7 billion through 2050 and $132.6 and $362.4 billion through 2100. Not surprisingly, the southeast displays the largest potential vulnerability, with the northeast ranking second above both the Gulf coast and the west coast.     

Armoring Against Coastal Climate Adaptation in the US: A Massachusetts Perspective

Massachusetts, like many coastal states in the US, stands to be impacted from climate-induced sea level rise. As a result, climate-sensitive coastal policy instruments are critical for providing adequate adaptation options, including an option to allow coastal features to migrate inland. But the migration of coastal features is under threat due to extensive private armoring. This essay highlights specific regulatory instruments at the federal and state level dealing with hard armoring using Massachusetts as an example. It argues specific federal and state regulations legitimize and incentivize hard armoring over other coastal land use planning methods. The current level of armoring in Massachusetts is highlighted and implications under current federal and state policy frameworks are explained. Suggestions for coastal states planning for sea level rise are discussed, including the need for state planning to take the lead. Recommendations for changes at the federal level are also highlighted.     

Institutional arrangements for coastal conservation in New Zealand

Abstract

The focus of this paper is institutional arrangements for initiative coastal conservation in New Zealand. “Initiative”; conservation refers to positive measures for the protection of the natural environment for reasons related to its inherent worth. Case studies were undertaken in five areas with different biophysical and societal characteristics, where various approaches to coastal conservation are being attempted. In each area, an issue was analyzed to identify conservation policies and their relationship to ecological and human needs, and to administrative and legal frameworks. Analysis demonstrated that initiative conservation policy can encompass user and community needs while maintaining ecological priorities. Institutional arrangements do not appear to restrict the development of this type of policy in New Zealand, but they do limit its formal expression and implementation. Arrangements for cohesive conservation areas spanning the land‐sea interface are particularly lacking.     

Israel's coastal program: Resource protection through management of land use

Abstract

Presently, much of Israel's 190‐kilometer‐long Mediterranean coast is either unoccupied, devoted to unsuitable uses, or is in use by activities which have no special need to be near the water's edge. This has resulted from years of lack of appreciation by policy‐makers of the coast as a valuable resource, of national development policies that directed attention to other regions, and of the relatively limited demand for coastal recreation.

In the last decade the importance of these factors has diminished. In turn, there is now mounting pressure for the development of coastal land. Increasingly, rising standards of living with a greater demand for recreational facilities, the growth of tourism as a major industry, and demands of the environmental lobby for conservation of part of the coastal land are factors bound to cause intensive change along the coast and to affect the quality of its resources. These trends have brought about public intervention in deciding the future of the coast. This paper reviews and analyzes Israel's coastal policy and its resource management programs, and also discusses the potential challenges to their full implementation.

Three types of programs were suggested as the main management tools: a coastal research and development effort, national coastal land use planning and pollution prevention, and monitoring and control programs. Major objectives of the programs were to be achieved through land use controls. Consequently, an important role is given in the development and implementation of the coastal program to agencies responsible for the management of physical land use planning and development.

Successful implementation of the management program, however, will depend on the ability of its administrators to coordinate the actions of many interests, on success in changing attitudes among decision‐makers as to the value of the coast, and on widening support for coastal resource conservation among a presently uninvolved public.     

Resilience of Touristic Island Beaches Under Sea Level Rise: A Methodological Framework

This contribution addresses the need for a simple model for managers to employ when planning strategies for the management of touristic beaches under sea level rise. A methodological framework was developed and tested in two Aegean archipelago islands (Lesvos and Rhodes, Greece). The scheme can represent the status of touristic island beaches, based on easily obtained variables/indicators and projections of beach erosion/retreat under different scenarios of mean sea level rise (MSLR) and extreme events. Information on beach geomorphological characteristics, environmental setting, water quality, management, and services (such as those used in the “Blue Flag” classification) was collated/collected and beach erosion/retreat due to CV & C was estimated through suitable ensembles of cross-shore (1-D) morphodynamic models. A Strength-Weaknesses-Opportunities-Threats (SWOT) framework was employed to assist in the selection of indicators and multicriteria analysis used to optimize indicator weights and rank beaches according to their sustainability under sea level rise. Implementation of the framework at the two islands has shown that: the majority of Lesvos and Rhodes beaches (82% of a total of 217 beaches and 58% of a total of 97 beaches, respectively) can be classified as beaches with no, or minimal, human interference, suggesting that under environmentally sound coastal management further touristic development might be afforded; there could be very significant effects of the sea level rise on the carrying and buffering capacities of the most developed (“Blue Flag”) beaches, with some expected even under conservative projections to be completely eroded by 2100, unless technical adaptation measures are taken; and using the proposed framework, touristic beaches can be rapidly ranked in terms of their resilience to sea level rise and their development potential, allowing prioritization of effective management responses.     

Implementing coastal zone management: 1972–1990

Abstract

The implementation history of the Coastal Zone Management Act offers insights into the process of long‐term intergovernmental policy implementation. This five‐stage history is explained as a coproduction process, in which coastal state, environmental, and development advocacy coalitions interacted with congressional committees and the federal coastal office to shape coastal policy and manage coastal development. The coproduction approach proved invaluable during the Reagan assault on the coastal program, when the states and Congress assumed responsibility for keeping the program alive. Acknowledging underlying stakeholder dynamics as the basis for coastal program evaluation could strengthen future coastal management implementation.     

Model coastal zone statute

Abstract

This model statute sets out a mechanism for the management of the coastal zone by the coastal states. It provides a possible state response to the Coastal Zone Management Act of 1972. The authors recognize that most states presently have some form of management or legal control over their coastal zone, and the model statute has been written with the intention that all or parts of it could be adapted to the wide variety of state regulatory schemes with the aim of providing unitary management to the valuable resource of the coastal zone.     

Clean Water Act Section 404 and Coastal Marsh Sustainability

The “no net wetland loss” goal has not been met in urban coastal regions where conditions continue to exacerbate wetland losses. Under the Clean Water Act (Section 404) the U.S. Army Corps of Engineers and U. S. Environmental Protection Agency share responsibility for regulating placement of fill material in wetlands. The `no discharge of fill' rules threaten coastal wetlands with continuing losses due to effects of changing climate, including rising sea levels, higher storm surges, and flooding. Where inland migration is limited by development, or where sediment accretion rates are lower than the rate of sea level rise, urban wetlands will be lost unless marsh topography is elevated. We explored regulatory and design approaches in recent Hudson-Raritan Estuary (HRE), San Francisco Bay Estuary and coastal Louisiana restorations, including creation of new marshland using dredge material. Questions related to sea level rise, ecological position within the landscape, or potential effects of extreme storm events were not addressed in the HRE restoration designs; these concerns were taken into account in other regions. We suggest benefits of marsh `replenishment' should be acknowledged in Federal regulatory policy and that consistent policies supportive of low-lying coastal marsh preservation in all regions should be enacted.     

Management considerations for accreting shorelines

Abstract

Natural coastal accretion in the United States occurs at river mouths, spits across embayments, inlets, capes and cuspate forelands, and pocket beaches. Human‐induced accretion occurs updrift of groins and jetties, landward of breakwaters, and in locations which are artificially nourished. Coastal accretion is usually temporary (years to tens of years). Erosion may occur due to deflection of streams and tidal current channels or to changes in sea level, weather patterns, or sediment budgets. A focus on ownership disputes or use of accreted land draws attention away from the long‐term problem of the development of land which may be subject to future erosion. Control mechanisms should be in place to direct development on accreting shorelines to make more effective use of the resource.     

Assessing economic activity in coastal areas: A shift‐share approach

Abstract

An essential aspect of economic analysis associated with planning efforts is identifying the composition of existing economic activity and understanding historical trends in economic change. The shift‐share model is a useful and inexpensive tool for this purpose. Shift‐share analysis evaluates changes in local economic activities relative to changes in a reference area (usually the state or nation). Economic change is separated into a reference area component, an industry mix component, and a local share component. These measure, respectively, the effect on the local economy due to changes in the reference area, factors specific to the local mix of industries, and the changing competitive position of the local area relative to the reference area.

A shift‐share analysis of Florida's coastal counties reveals that all grew much faster over the 1965–1975 period than did the national economy. This rapid growth is primarily a result of a net shift of economic activity toward the study area relative to the nation. However, a few coastal counties did exhibit a mix of slow‐growing industries. Specific industry results for Florida counties at the eighty‐industry level reveal that many industries showed significant shifts toward Florida's coastal counties. The performance of individual industries in the coastal counties generally exceeded that of the same industries in noncoastal counties.     

Vulnerability of Caribbean Island Cemeteries to Sea Level Rise and Storm Surge

The Intergovernmental Panel on Climate Change reports that rising seas by the end of this century will increase the severity of coastal flooding and erosion. The Caribbean region is home to many small islands that are vulnerable to sea level rise and storm surge. Much of the literature examining impacts of sea level rise in the Caribbean focuses on ecosystems, infrastructure, and recreation. Few studies have examined how sea level rise will impact historic and culturally important places. In an effort to address this research gap, geographic information systems and crowd-sourced, georeferenced photographs were used to build a first-of-its-kind database of 542 Caribbean small island cemeteries. Vulnerable cemeteries were then identified based upon elevation, proximity to the ocean, and the coastal profile. Over one-fifth of the cemeteries surveyed are within 100 m of the coast. The highest concentrations of vulnerable cemeteries are on flat islands such as the Cayman Islands. Yet, some mountainous islands such as Saint Martin also have potentially vulnerable cemeteries. These findings suggest that the bereaved, cemetery managers, and managers of coastal areas that have cemeteries may have additional considerations when making long-term decisions about where and how to bury the deceased.     

Sea level and Eddy Kinetic Energy variability in the Bay of Biscay, inferred from satellite altimeter data

Twelve years (1993–2005) of altimetric data, combining different missions (ERS-1/2, TOPEX/Poseidon, Jason-1 and Envisat), are used to analyse sea level and Eddy Kinetic Energy variability in the Bay of Biscay at different time-scales. A specific processing of coastal data has been applied, to remove erroneous artefacts. Likewise, an optimal interpolation has been used, to create a series of regional Sea Level Anomaly maps, merging data sets from two satellites.The sea level presents a trend of about 2.7 mm/year, which is within the averaged values of sea level rise in the global ocean. Frequency spectra show that the seasonal cycle is the main time-scale affecting the sea level and Eddy Kinetic Energy variability. The maximum sea level occurs in October, whilst the minimum is observed in April. The steric effect is the cause of this annual cycle. The Northern French shelf/slope presents intense variability which is likely due to internal tides. Some areas of the ocean basin are also characterised by intense variability, due to the presence of eddies.The Eddy Kinetic Energy, in turn, is higher from December to May, than during the rest of the year and presents a weak positive trend from April 1995 to April 2005. Several documented mesoscale events, occurring at the end of 1997 and during 1998, are analysed. Altimetry maps prove to be a useful tool to monitor swoddy-like eddies from their birth to their decay, as well as the inflow of seasonal slope water current into the southeastern corner of the Bay of Biscay.     

Support for Oregon land‐use planning: A multi‐level analysis

Abstract

This article analyzes support for and opposition to state land‐use planning in Oregon, using voting records from the 1976 referendum to repeal Oregon's regulatory legislation and survey data. Support for controlled growth legislation is found to be a product of both individual‐level characteristics and characteristics of the larger community where one resides. The most influential contextual variables are the county's economy and the class composition of the city. The authors conclude that coastal zone managers must exercise caution when interpreting individual survey data which indicate support for various environmental concerns. Contextual differences must be taken into consideration because sources of support for coastal zone management may vary among individuals, depending on the nature of the communities in which they live.