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1.
A dynamical method of initializing the primitive equations is tested and used to diagnose the three-dimensional circulation associated with jets and eddies as found in the California coastal transition zone (CTZ). The initialization method, referred to as digital filter initialization (DFI), was recently developed by [Monthly Weather Review 120 (1992) 1019] for use in an intermittent data assimilation system in the atmosphere. The ability of DFI to recover the mesoscale ageostrophic circulation associated with finite amplitude jets and eddies in the ocean is first demonstrated using control data produced by simulations with a primitive equation model. The DFI method is then applied to synoptic hydrographic data collected during several California CTZ surveys in the summer of 1988. The diagnostic results indicate the existence of jets, eddies, and filaments in the CTZ domain with maximum horizontal currents of the order of 0.6 m/s at the surface. Currents associated with such jets and filaments are coherent to a depth of over 500 m. The surface currents associated with a prominent cool filament are generally confluent, and weakly convergent on average, along the 270 km offshore extent of the filament. Meanders in the jet display convergence and downwelling upstream of pressure troughs and divergence and upwelling downstream of the troughs. Maximum vertical velocities at 100 m are of the order of 10 m/day. This result is consistent with independent estimates of subduction rates made from biological studies in this and similar coastal filaments in the CTZ program. 相似文献
2.
Merle R. Sowman 《Coastal management》2013,41(3):163-184
Abstract In this article, an overview of the status of coastal zone management (CZM) in South Africa is presented. Firstly, it provides background to the development of various initiatives to promote sustainable use of coastal resources within the context of sociopolitical changes in South Africa. Thereafter, it examines the progress made with respect to key attributes underpinning most CZM programs. Finally, it identifies obstacles to achieving effective CZM in South Africa and makes recommendations to address these shortcomings. The review reveals that whilst considerable progress has been made in certain areas of program development, such as resource conservation and pollution control, there are several gaps and inadequacies within existing efforts. These include the absence of a clear policy to guide efforts, lack of coordination amongst government departments involved in CZM, as well as inadequacies in our legal and administrative system. The promulgation of a Coastal Zone Management Act and the establishment of a Coastal Unit charged with the coordination and review of all activities impinging on coastal resources are amongst the recommendations made. 相似文献
3.
Joachim F. Wohlwill 《Coastal management》2013,41(3-4):225-248
Abstract The focus of this paper is theoretical, as well as methodological. It reviews previous studies of visual impact and reports research by the author on people's evaluation of the appropriateness of different man‐made facilities in different coastal‐area contexts and other environments. In this study, subjects were asked to react to slides developed through the use of landscape models and experimental facilities to simulate the appearance of a building in the landscape, while systematically varying the visual relatedness between the two. Specific interest centered on the variable of congruity vs. contrast between the appearance of the building and its landscape context, manipulated by co‐varying the attributes of color and size to create a five‐point scale of contrast/obtrusiveness. The hypothesis was that judgments of appropriateness, and to a lesser extent judgments of liking, would vary inversely with level of contrast. The role of two further variables, the functional significance of the building in its setting, and the character of the setting itself, was also investigated. The author reviews methodological issues involved where subjects respond to visual stimuli for purposes of judging change in visual quality. These methodological issues include: stimulus‐selection and problems of simulation, choice of response measures, and choice of respondents, and the treatment of individual differences. The author calls for development of standardized scales and indices such as “perceptually‐relevant environmental quality indicators.” 相似文献
4.
Howard Ris 《Coastal management》2013,41(3-4):299-311
Abstract This paper concerns the limitations on integrating visual management into the coastal zone planning process as exemplified by the Commonwealth of Massachusetts, a state with a strong tradition of “home rule”; and a CZM implementation program based on a “networking”; of existing state authorities. The implications of the Massachusetts experience are that: (a) management of esthetic resources at the state level continues to be much less of a priority than management of ecological resources such as wetlands or floodplains; (b) visual management has yet to engender a strongly supportive constituency beyond that concerned with historic preservation; (c) project review focusing on visual impacts may be a more appropriate activity for local rather than state government; and (d) the technical aspects of visual management or impact assessment are far more advanced than their political acceptability. Political realities, together with the decision that implementation of the program should be based on a networking of existing authorities, thus determined the degree to which visual management could be incorporated into the state's program. As a result, the program's principal instruments of visual management became a strengthening of existing programs such as Wild and Scenic Rivers, reliance on wetland protection statutes to indirectly protect natural scenic values, and the use of the federal consistency provisions of the Coastal Zone Management Act to foster focused growth patterns through provision of publicly funded infrastructures. Esthetically oriented project review, with the exception of potential impacts on historic sites, was left to the discretion of local government, and a technical assistance program was created to provide funding or professional skills to communities interested in developing their own esthetic controls or design review processes. Maine, Rhode Island, and other New England states have followed a similar course. 相似文献
5.
Arnold W. Mantyla Steven J. Bograd Elizabeth L. Venrick 《Journal of Marine Systems》2008,73(1-2):48-60
Factors that influence the magnitude and the depth of the chlorophyll maximum layer in the ocean off Southern California are explored using observations from the long-term California Cooperative Oceanic Fisheries Investigations (CalCOFI) program. The data record is sufficiently long to reveal patterns not always evident from single stations or single cruises. Processes such as coastal wind-driven upwelling, geostrophic circulation, and annual physical and chemical cycles are illustrated to demonstrate their effect on euphotic zone nutrient availability, and subsequent phytoplankton biomass and primary productivity. In this area, where the influence of wind-driven upwelling is spatially restricted and advected waters are generally nutrient depleted, geostrophically induced upwelling and winter convection become important in determining spatial and temporal patterns of phytoplankton. 相似文献
6.
Bryan H. Farrell 《Coastal management》2013,41(1-2):113-130
Abstract Most tourist development takes place in the coastal zone. Concentrated tourist use continues in spite of opposition by groups who feel that any tourism, especially international, threatens both the natural environment and local values. Although shorelines and “coastscapes”; belong to all, decisions regarding them are made by relatively few. The number of community organizations involved in coastal zone management decisions varies from almost none in some Third World countries to dozens in places like Hawaii or California. Constructive use of coastal zones requires an understanding of the interactions between biophysical and social systems. Planning tourism in this context requires that all groups with an interest in the coastal zone join in a new “cooperative tourism”; in which all contribute to decisions and face ultimate responsibilities. 相似文献
7.
Newell Garfield Mathew E. Maltrud Curtis A. Collins Thomas A. Rago Robert G. Paquette 《Journal of Marine Systems》2001,29(1-4)
During the period 1992–1998, 38 isobaric RAFOS floats were deployed to sample the subsurface flow of the California Undercurrent. The deployments, released over the California continental slope west of San Francisco, have sampled robust year-round poleward subsurface flow associated with the Undercurrent most seasons and the combined inshore current and Undercurrent in winter. Two other types of flow have been seen: a region of weak flow with little net displacement just west of the California Undercurrent, and an active westward propagating eddy field. This eddy field appears to be the primary mechanism for moving floats from the Undercurrent into the ocean interior. The observations and statistics from the RAFOS floats are compared with Lagrangian estimates of particles tracked in a global high resolution ocean simulation in order to evaluate the fidelity of the model along an eastern boundary. The results show that the model reproduces the general character of the flow reasonably well, but underestimates both the mean and eddy energies by a substantial amount. 相似文献
8.
节能住宅,是高效低耗、健康舒适的高质量居住建筑,属于可持续发展建筑的一种。本文从建筑环境的营造和建筑主体节能措施两个方面进行阐述,主要从外墙外保温、屋顶保温、门窗保温来说明建筑主体节能的措施。 相似文献
9.
Abstract Coastal zone management in Oregon is based on the state's general land‐use law. This body of law is designed to deal with population increase, urbanization, and preservation of agricultural land, as well as with other problems throughout the state. Early planning and policy recommendations for the coast were in the hands of a commission having predominantly local membership. This commission produced an extensive series of studies, policies, and recommendations which were assembled as a proposed management tool for natural resources. Staff of the commission was then absorbed into the state land‐management agency, which developed final goals and guidelines for compliance with the Coastal Zone Management Act. Adoption of the coastal goals in December 1976 has triggered deadlines for local government compliance within the coastal zone. The management program is now undergoing federal review. 相似文献
10.
Nan Evans 《Coastal management》2013,41(3):189-213
Abstract Greater commitments of aquatic resources are required as aquaculture activities expand and intensify. At the same time, increasing recreational and residential uses of the coast are placing other demands on many of the same resources. Multiple use disputes are arising and conflicts are intensifying. This paper is a problem analysis based on recent public debates in the state of Washington which surrounded the mechanical harvest of clams, raft culture of mussels, and pen rearing of salmon. Subjects of potential conflict are shown in the questions of continuing the subtidal harvest of geoducks, raft culturing of marine algae for food and chemical extracts, and continuing the use of public nearshore aquatic areas for private oyster farming. This report also suggests that better coastal management techniques need to be developed which address: (1) how environmental impacts and risks are determined; (2) how claims for esthetic quality can be evaluated and measured; and (3) which methods can be used to plan for the aquatic areas which recognize the special features of the aquatic areas. 相似文献
11.
Seoung‐Yong Hong 《Coastal management》2013,41(4):391-415
Abstract The physical characteristics of Korea have had a profound impact on the uses of the coastal zone that have, in turn, been determined by and reinforced the nation's economic development strategy. While coastal zone management in many developed economies is more heavily oriented toward environmental protection and the resolution of user conflicts, policies for coastal zone management in Korea have emphasized the role of coastal space and other resources for economic development and industrial needs. Increasing demand for land reclamation to provide ever‐increasing industrial sites and human settlements, traditional and future needs of the fishery, and concern for the environment have led to a vast array of competition and, finally, often to conflicts. The basic pattern of coastal zone use in Korea has changed from the linear expansion of coastal zone to integrated coastal uses. An increased number of critical coastal zone issues and interactions was reflected in the creation of new governance that dealt with coastal zone resources and environment. 相似文献
12.
Peter Grenell 《Coastal management》2013,41(1):13-20
Abstract This paper examines the activities of the California State Coastal Conservancy. It will examine the agency's procedures and identify those factors critical to its success. Finally, suggestions for improvements in its operations are given. 相似文献
13.
Key to the predictive understanding of many nearshore marine ecosystems is the transport of larvae by ocean circulation processes. Many species release thousands to billions of larvae to develop in pelagic waters, but only a few lucky ones successfully settle to suitable habitat and recruit to adult life stages. Methodologies for predicting the larval dispersal are still primitive, and simple diffusive analyses are still used for many important applications. In this study, we investigate mechanisms of larval dispersal using idealized simulations of time-evolving coastal circulations in the California Current system with Lagrangian particles as models for planktonic larvae. Connectivity matrices, which describe the source-to-destination relationships for larval dispersal for a given larval development time course, are used to diagnose the time–space dynamics of larval settlement. The resulting connectivity matrices are shown to be a function of several important time scales, such as the planktonic larval duration, the frequency and duration of larval release events and inherent time scales for the coastal circulations. Many important fishery management applications require knowledge of fish stocks on a year-to-year or generation-to-generation basis. For these short time scales (typically less than 1 year), larval dispersal is generally far from a simple diffusive process and the consideration of the stochastic and episodic nature of larval dispersal is required. This work provides new insights into the spatial–temporal dynamics of nearshore fish stocks. 相似文献
14.
Rutherford H. Platt 《Coastal management》2013,41(3):265-284
The ocean and Great Lakes coasts of the United States are experiencing widespread economic and environmental damage from coastal flooding and erosion. During this century, public response to such coastal hazards has evolved haphazardly in response to particular disasters. Over time, however, the range of response has broadened as research has helped to refine public understanding of physical coastal processes, and specific disasters have been studied before longer term forms of institutional response have been formulated. Earlier reliance on engineered shoreline protection has been supplemented by beach nourishment, flood insurance, building and land use regulations, coastal zone planning, and other approaches. This article interprets the evolution of such public policy innovations in terms of a model that depicts the interaction of spatially differentiated systems of physical, legal, and cultural phenomena in the coastal context. 相似文献
15.
R. Bruce Rettig 《Coastal management》2013,41(3):291-303
Abstract Recent land use legislation pays particular attention to the coastal zone where age‐old conflicts have recently accelerated. Flexibility is required in policy because visible conflicts are tied into complex physical and social systems which may require changing patterns of land use over time. Public policy is altering property rights and a thorough understanding of the economic and social roles played by those rights is required. Economic models can be used to understand some major changes such as types of alteration of the environment, but may be ignored or misused unless a better understanding of coastal decision processes is developed. 相似文献
16.
A method is introduced to determine the uncertainties in the predictions of oil spill trajectories using a classic oil spill model. The method considers the output of the oil spill model as a function of random variables, which are the input parameters, and calculates the standard deviation of the output results which provides a measure of the uncertainty of the model as a result of the uncertainties of the input parameters.In addition to a single trajectory that is calculated by the oil spill model using the mean values of the parameters, a band of trajectories can be defined when various simulations are done taking into account the uncertainties of the input parameters. This band of trajectories defines envelopes of the trajectories that are likely to be followed by the spill given the uncertainties of the input.The method was applied to an oil spill that occurred in 1989 near Sines in the southwestern coast of Portugal. This model represented well the distinction between a wind driven part that remained offshore, and a tide driven part that went ashore. For both parts, the method defined two trajectory envelopes, one calculated exclusively with the wind fields, and the other using wind and tidal currents. In both cases reasonable approximation to the observed results was obtained.The envelope of likely trajectories that is obtained with the uncertainty modelling proved to give a better interpretation of the trajectories that were simulated by the oil spill model. 相似文献
17.
Abstract A survey of coastal state legislation reveals several types of statutes affecting activities occurring in coastal regions: Coastal management statutes, wetland statutes, and shoreline statutes. Each coastal state has adopted methods to delineate coastal areas or features, whether an entire coastal zone, a limited feature such as wetlands, or shorelands. Boundary delineation is done according to linear measurements, political boundaries, roads and highways, vegetation, elevation, tidal flow, and other factors. An appendix is provided containing state statutory provisions relating to boundary‐delineation techniques. 相似文献
18.
Kary Coleman 《Coastal management》2013,41(5):484-494
The welfare of the marine environment is threatened worldwide. In order to maintain ecosystem services management must shift from single sector to ecosystem approaches. To support this transition in marine management, this article reviews collaborative ecosystem-based management in the California Current Large Marine Ecosystem (CCLME), through an overview and comparison of three collaborations on the United States West Coast of California, Oregon, and Washington. The achievements of these collaborations are demonstrated. Networking and extending collaboration throughout the entire region is shown to be essential for environmental conservation and sustainable development in the CCLME. 相似文献
19.
结合水运工程房建项目的特点,以上海港外高桥港区六期房建项目的实例,分析了水运工程房建项目的特点,并提出了监理单位在水运工程房建项目监理组织协调的作用、内容、方法和改进提高的措施。 相似文献
20.
Abstract This article argues that using the public sector and the private market in the historically delineated and traditional ways offers only the bluntest of tools with which to approach the complex problem of coastal zone management. It therefore seeks to provide a basis for reformulating our understanding of sectoral responsibility with regard to resources management. First, it conceptually analyzes the relative strengths and weaknesses of the two sectors. Second, it examines three examples of coastal resources management—beaches and shorelands, artificial reefs, and coastal wetlands—in analyzing the complexities of the coastal management challenge and the limitations of our current approaches. Finally, we provide an alternative perspective on how these common property resource allocation decisions can be made. 相似文献