The coastal zone1 represents only 17 percent of the land area of the United States, yet it is one of the nation’s greatest environmental, social, and economic assets. Our lives and economy are inextricably linked to the features and activities found in the coastal zone. It is a nexus for tourism and industry, including activities such as shipping and boating; commercial and recreational fishing; exploration and extraction of oil, natural gas, gravel, and sand; recreational use of beaches; and wildlife observation (see Box 1.1). The coastal zone is densely populated and highly developed, and yet it is also where important habitats such as forests, rivers and streams, wetlands, estuaries, beaches, barrier islands, and the coastal ocean occur. These habitats, which individually support their own unique assemblages of plants and animals, are also complexly linked with—and dependent on—the coastal environment.
More than 80 percent of the American population lives within 50 miles of the coast, a population component that has doubled in the past decade. By 2010 the population density along ocean shores is projected to reach 400 people per square mile, compared to less than 100 per square mile for the rest of the nation. Fourteen of the country’s 20 largest urban corridors are along the nation’s coasts, and a major portion of the U.S. economic
infrastructure is located near or on the ocean (Hinrichsen, 1999). More than 95 percent of overseas trade between the United States and other nations moves by ship, including 9 million barrels of oil per day and over 98 percent, by weight, of all non-North American Free Trade Agreement (NAFTA) goods imported into the country. As gateways to our nation and the focal point of commerce, our ports and harbors are critical and vulnerable components of the nation’s infrastructure and homeland security.
Beyond its formal, spatially delimited definition, the coastal zone is inextricably linked to a complex web of environments extending from the upper parts of watersheds out to the open ocean. Variations in watershed outflows influence the types and concentrations of dissolved and suspended materials in coastal waters. Physical, chemical, and biological processes control the distribution of nutrients, the transport of sediment, and the water circulation in coastal waters. Human activities have often resulted in increased sediment and pollution loads to coastal waters, decreased water quality, alteration of physical environments, loss or change of habitat (both onshore and offshore), depletion of fish stocks
and other resources, and degradation of coastal aquifers. Thus the coastal zone provides a critical and sensitive indicator of environmental perturbations and disruptions.
Weather and climate also have a major impact on the coastal zone. Between 1980 and 2001, total economic losses in the coastal region due to weather-related events exceeded $280 billion (Ross and Lott, 2000). Most climate change models predict a rise in sea level and an increase in the frequency and severity of weather-related events over the coming years, which would put even more pressure on the fragile coastal zone (IPCC, 2001).
The importance of the coastal zone to the well-being of the nation places tremendous demands and responsibilities on those charged with management of this critical environment. In order to understand and address the effects of complex natural and anthropogenic forces in the coastal zone, a holistic multidisciplinary framework must be developed to adequately describe the interconnectivity of processes in the system. At the base of this framework will be accurate information about the locations of important features and processes, both onshore and offshore.
COASTAL ZONE GEOSPATIAL DATA—MAPPING AND CHARTING
The locations of features in space are described by geospatial data. These data—whether in the atmosphere, on or below the earth’s surface, or within the water column—are referenced to a specific position in space and then linked to information about the attributes associated with that position. Such geospatial data are usually presented in the form of maps or charts.
Science, education, commerce, planning, and resource management have relied for centuries on the availability of accurate maps and charts. In coastal regions, high-quality maps and charts are essential for safe navigation, resolving jurisdictional boundaries, understanding processes, mitigating hazards, tracking environmental changes, establishing inventories of resources and habitats, and developing new programs and policies. Ideally, to accomplish all of these goals it will be necessary to combine disparate coastal zone information (e.g., land features, water depths, salinity, currents, bottom type, habitat type, infrastructure) into a single distributed information system that uses spatial coordinates as a common reference frame. These data can then be depicted on maps and charts or brought into Geographic Information Systems (GISs), or other spatially referenced software applications, for analysis. While simple in concept, the reality of this integration of coastal zone data is extremely complex. Those interested in truly understanding the complexities of the
coastal zone will need to reach beyond traditional geographic, disciplinary, and political boundaries to develop a new suite of methods, analytical tools, and products.
Historically, the fundamental data needed in the coastal zone have been captured and portrayed onshore as “maps” and offshore as “charts.” Unfortunately, differences in scale, resolution, cartographic conventions and projections, and particularly reference datums currently inhibit the seamless combination of existing onshore and offshore data. The result is a lack of standardized uniform geospatial products that span the coastal zone. This inability to produce a seamless map (or chart) across the land-water interface is a severe impediment to studying the many processes that are continuous across the shoreline, particularly studies of coastal change. The lack of standardization has also led government agencies, the research community, and the private sector to undertake the expensive and time-consuming task of separately generating new data and maps to accompany almost all new studies and initiatives. The lack of coordination of coastal zone mapping efforts inevitably leads to the potential for redundancy of surveys or products.
At the national level, at least 15 federal agencies are involved in the primary collection or use of coastal geospatial data (see Appendix A), often with responsibilities shared among multiple divisions within the same agency. In addition to these federal agencies, a plethora of state and local agencies, academic institutions, and other organizations also gather and use coastal zone information. This has resulted in a chaotic collection of potentially overlapping, and often uncoordinated, coastal mapping and charting products that can frustrate the efforts of users to take advantage of existing datasets and build on past studies. Add to this mix an increasingly educated and interested public, with growing demands for information to meet their diverse interests (including environmental protection, commerce, and recreation), and it becomes even more critical for the nation to pursue integrated coastal and ocean mapping in a cost-effective, well-coordinated, and strategic manner.
Fortunately, recent advances in mapping technologies, remote sensing, global positioning, data handling, and computing technologies—particularly the rapid development of GISs—have radically changed the density, accuracy, timeliness, and inherent nature (now mostly digital) of coastal mapping data and data products. In addition, programs and entities such as the National Ocean Partnership Program (NOPP) and the Federal Geographic Data Committee (FGDC) are promoting a greater spirit of partnership among those involved in coastal zone studies. These new tools and mechanisms, together with the implementation of appropriate and well-designed standards, should enable a more thorough, integrated, and organized approach to coastal zone mapping.
COMMITTEE CHARGE AND SCOPE OF THE STUDY
Recognizing both the difficulties and opportunities described above, and believing that an independent external evaluation could provide valuable new ideas, the National Oceanic and Atmospheric Administration (NOAA), the U.S. Geological Survey (USGS), and the U.S. Environmental Protection Agency (EPA) requested and funded this assessment by the National Academies of national needs for coastal mapping and charting (see Box 1.2).
The mandate of the committee can be summarized in four questions:
What are the mapping needs of the coastal community?
Who is doing what?
Are there gaps or overlaps in existing efforts?
How can the needs of the community be met in the most efficient and effective way possible?
This study will identify and suggest mechanisms for addressing national needs for spatial information in the coastal zone. By examining the major spatial information requirements of federal agencies, as well as the principal user groups they support (e.g., state and local coastal managers, urban planners, resource managers, maritime industry), the committee will identify high priority needs, evaluate the potential for meeting these needs based on the current level of effort, and suggest steps to increase collaboration and ensure that the nation’s need for spatial information in the coastal zone is met in an efficient and timely manner.
In particular, the committee will identify:
Identifying the needs and activities of the U.S. coastal zone community is an immense task. To conduct this assessment, the committee held four regional meetings at which representatives of agencies involved in all aspects of coastal zone mapping made presentations and offered their perspectives on the needs and activities of their agencies. In addition to these presentations, the committee communicated with and received written and oral submissions from individuals involved in coastal zone mapping activities. The requirement in the committee’s statement of task for an assessment of the major spatial information requirements of federal agencies, as the basis for federal support of a wide range of user groups, has led to the committee’s focus on making recommendations that predominantly apply at the federal level. Nevertheless, underpinning the committee’s recommendations is an appreciation that a broad range of user groups, including state and local agencies, constitute the “frontline” for coastal zone activities and that improved federal-level mapping and charting activities must have the provision of improved information at these other levels as its focus.
The committee was required to prepare an interim report (NRC, 2003a) that focused on a compilation of the coastal mapping and charting activities of federal agencies and offered some very preliminary observations. A tabular summary of the agency activity compilation that constituted a major component of the interim report is presented in Appendix A.
Despite the complexities of the numerous issues raised by the many providers and users of coastal zone data, the consistency of needs and concerns permitted the committee to quickly converge on a vision for the future of coastal mapping and charting. This vision requires the development of an integrated and coordinated coastal mapping strategy for the nation, based on a foundation—a reference frame—upon which all data collection, analyses, and products can be built. To establish this foundation, there must be a national effort to collect the information and develop the tools necessary to seamlessly blend topographic (onshore) and bathymetric (offshore) data. These data and tools will permit the establishment of a nationally coordinated distributed digital database across the land-sea interface consisting of seamless elevation and depth data that can be referenced or transformed to common vertical and horizontal datums. This database will provide the basic geospatial framework for all subsequent data products, much like the USGS topographic sheet basemaps have formed the onshore foundation for a multitude of subsequent studies. Unlike the USGS topographic sheets, however, a coastal zone database must be “tide-aware” and must be able to reconcile the differences between onshore and offshore datums.
Our vision for the future of coastal zone mapping and charting also includes mechanisms to ensure communication among all the agencies
and entities involved in order to minimize redundancy of efforts and maximize operational efficiencies. There will be national—and perhaps international—standards and protocols for data collection and metadata creation and readily available tools for data transformation and integration. With these tools, the user community will be able to evaluate the accuracy and timeliness of data and change scales and projections, as well as seamlessly merge disparate datasets. The database and data integration tools will be easily accessible to all users, public and private, from a single digital portal accessible through the Internet.
This is a bold vision, but at the same time an obvious one. Who would argue with a system that is efficient and produces easily accessible, fully interchangeable, accurate, and timely data? The vision may be simple to define, but its implementation will be anything but simple. As discussed in the following chapters, there are serious impediments to attaining this vision. It is the committee’s hope, however, that the strategies outlined here will help the nation to get there. The long-term sustainability of our coastal resources may well depend on it.