(2000), there were just over 2.2 billion people living within 100 km (62 miles) of a
coast in 1995. The coastal zone as a land cover class only accounts for twenty percent
of all land area. Most lands within the zone have been permanently altered. Apart from
Antarctica, 19% of all landmass within 100 km of the coast are classified as agricultural
or urban areas; 10% are classified as a mosaic of natural and altered vegetation; and
71% are classified in the least modified category. A significant percentage of this least
modified class incorporates many uninhabited areas in northern latitudes. Within this
coastal zone, numerous coastal habitats are quickly vanishing, such as wetlands,
mangroves, coral reefs, and seagrasses (WRI 2000, Edinger et al., 1998, Mumby et al.,
1999). Approximately 5-80% of original mangrove area in countries where such data
are available is believed to have been lost. Many coastal ecosystem communities have
been significantly altered by anthropogenic changes to the landscape. These changes, in
turn, can negatively impact coastal habitats such as coral reef and wetlands. An
example of use of remote sensing to detect such considerable change over time is
shown in Figure 1. Figure 1 also positively links the Reefs at Risk indicator with such
changes. Such widespread changes and losses have increased remarkably in the last 50
years (WRI, 2000). This is of direct concern for coastal managers since the different
ecosystems within the coastal zone include a myriad of habitats supporting juvenile and
mature aquatic species, and indigenous and migratory bird species. The coastal zone is
also increasingly under pressure by a growing population, and urban expansion and
development, all of which result in a loss of original habitat. Reports documenting the
extreme loss of coastal habitats have been produced sporadically. Herein lies the
importance of identifying archival datasets, data products, and sites of ongoing data
acquisition of remotely sensed data. Identifying sources of data, data products, and
ongoing efforts can lessen the cost of data and value-added product attainment. This
chapter provides a case study of an organization dedicated to coastal (and other) data
dissemination, a description of current archival data, and insight into the issues of data
integration. This chapter also discusses the integration of new and archival data and
how the integration of these datasets can provide insight into determining current and
future ecosystem change, variability, and management decisions. Since coastal
ecosystems are identified here as one of the fastest changing, highly altered ecosystems
on the planet, data sources that would benefit studies in this area will be the major focus
of this chapter. However, many of the data sources discussed could also be used in
support of research in other ecosystems.
2. Historical Satellite Imagery and Related Data Products
2.1 GLOBAL LAND COVER FACILITY (GLCF) – A CASE STUDY
In this section the most notable archive of available imagery in the United States,
the University of Maryland’s Global Land Cover Facility (GLCF), is discussed in
detail. Since this is the most comprehensive, free data distribution facility at the time,
other image archives will be mentioned (but not discussed at length) at the end of this
section for the reader’s reference. Not all of the mapping and data products available
are discussed, only those which could potentially be utilized in conjunction with
coastal or aquatic study.
The mission of the GLCF is “To create and communicate improved understanding
of the nature and causes of land cover change and its impact on the Earth System
through the use of remote sensing.” At the University of Maryland in 1993, the
184
Gebelein
coast in 1995. The coastal zone as a land cover class only accounts for twenty percent
of all land area. Most lands within the zone have been permanently altered. Apart from
Antarctica, 19% of all landmass within 100 km of the coast are classified as agricultural
or urban areas; 10% are classified as a mosaic of natural and altered vegetation; and
71% are classified in the least modified category. A significant percentage of this least
modified class incorporates many uninhabited areas in northern latitudes. Within this
coastal zone, numerous coastal habitats are quickly vanishing, such as wetlands,
mangroves, coral reefs, and seagrasses (WRI 2000, Edinger et al., 1998, Mumby et al.,
1999). Approximately 5-80% of original mangrove area in countries where such data
are available is believed to have been lost. Many coastal ecosystem communities have
been significantly altered by anthropogenic changes to the landscape. These changes, in
turn, can negatively impact coastal habitats such as coral reef and wetlands. An
example of use of remote sensing to detect such considerable change over time is
shown in Figure 1. Figure 1 also positively links the Reefs at Risk indicator with such
changes. Such widespread changes and losses have increased remarkably in the last 50
years (WRI, 2000). This is of direct concern for coastal managers since the different
ecosystems within the coastal zone include a myriad of habitats supporting juvenile and
mature aquatic species, and indigenous and migratory bird species. The coastal zone is
also increasingly under pressure by a growing population, and urban expansion and
development, all of which result in a loss of original habitat. Reports documenting the
extreme loss of coastal habitats have been produced sporadically. Herein lies the
importance of identifying archival datasets, data products, and sites of ongoing data
acquisition of remotely sensed data. Identifying sources of data, data products, and
ongoing efforts can lessen the cost of data and value-added product attainment. This
chapter provides a case study of an organization dedicated to coastal (and other) data
dissemination, a description of current archival data, and insight into the issues of data
integration. This chapter also discusses the integration of new and archival data and
how the integration of these datasets can provide insight into determining current and
future ecosystem change, variability, and management decisions. Since coastal
ecosystems are identified here as one of the fastest changing, highly altered ecosystems
on the planet, data sources that would benefit studies in this area will be the major focus
of this chapter. However, many of the data sources discussed could also be used in
support of research in other ecosystems.
2. Historical Satellite Imagery and Related Data Products
2.1 GLOBAL LAND COVER FACILITY (GLCF) – A CASE STUDY
In this section the most notable archive of available imagery in the United States,
the University of Maryland’s Global Land Cover Facility (GLCF), is discussed in
detail. Since this is the most comprehensive, free data distribution facility at the time,
other image archives will be mentioned (but not discussed at length) at the end of this
section for the reader’s reference. Not all of the mapping and data products available
are discussed, only those which could potentially be utilized in conjunction with
coastal or aquatic study.
The mission of the GLCF is “To create and communicate improved understanding
of the nature and causes of land cover change and its impact on the Earth System
through the use of remote sensing.” At the University of Maryland in 1993, the
184
Gebelein