Using Remotely Sensed Imagery for CZM
477
and air produces, together with human use of the marine and land coastal resource (for
infrastructure development, leisure and recreation, fishing, mineral extraction and power
generation), make it one of the most difficult areas of the world to manage and care for
(King, 1998). Management difficulties essentially arise from the high physical diversity
of the coastal system, with different coastlines varying in width, length, processes at
work and natural habitat. To coordinate a successful and holistic management of the
coastline, there is a need for data to be gathered within the natural coastal framework
which is up-to-date and relevant, and can help coastal managers formulate the
procedures that will balance human actions with the needs of the environment (King,
1998).
Despite the complicated nature of the coastal zone, its natural dynamics and
processes do in theory lend themselves quite well to scientific enquiry using
geographical principles. The coast is very spatially and temporally dynamic, with
human and natural objects, features and landforms all affecting each other in some way
across space and through time. Data collected about these will inevitably have a geospatial component, and this data can be stored, manipulated and analysed within a GIS
to produce models of reality which aid in our understanding of the environment.
Both GIS and remote sensing have been quite widely used in coastal research.
However, although GIS is good for the integration, management and analysis of data, it
is not a source of raw data or method of primary data collection. Remote sensing, on the
other hand is. Its many advantages include up-to-date data provision, or data on
demand; data acquisition without field visits; early identification of environmental
problems; the ability of satellites to image large tracts of the Earth (allowing managers
to view whole coastal systems); near real-time and real-time imagery, and more detailed
monitoring of coastal landscapes, habitats and processes using higher resolution
imagery such as aerial photography and videography (King, 1998). However, perhaps
its greatest advantage is that the data delivered is usually in a form that most people will
instantaneously recognise as a ‘snap-shot’ of the Earth. It is this instinctive recognition
that makes remotely sensed imagery one of the best sources of geo-spatial data, because
it can be interpreted to a certain extent by most people, and this level of interpretation
yields valuable information.
Such an instantaneous, and possibly instinctive recognition and comprehension
of features shown on a remotely sensed image is what, in many cases, makes this source
of data far more valuable than a map, because maps are a more abstract representation
of reality, and not everyone can read maps. Yet, lack of exposure to remote sensing
beyond perhaps the occasional aerial photograph (be it oblique or vertical), limits the
use and application of remote sensing by the non-specialist, to environmental
management. Indeed, it is the relative familiarity of true colour or black and white aerial
photography above satellite imagery and other airborne sensors that prevents a more
inventive use of remote sensing, because people automatically think of aerial
photography as the best imagery for the job.
There are a number of reasons why this might be the case. Firstly, both true
colour and black and white aerial photography is more likely to be easily understood by
most people. Secondly, many people prefer to work, or perceive that it is easier to work
with hard copy photographs, rather than a digital copy on a PC or workstation; and
thirdly, the greater spatial resolution of aerial photography, which provides better detail
477
and air produces, together with human use of the marine and land coastal resource (for
infrastructure development, leisure and recreation, fishing, mineral extraction and power
generation), make it one of the most difficult areas of the world to manage and care for
(King, 1998). Management difficulties essentially arise from the high physical diversity
of the coastal system, with different coastlines varying in width, length, processes at
work and natural habitat. To coordinate a successful and holistic management of the
coastline, there is a need for data to be gathered within the natural coastal framework
which is up-to-date and relevant, and can help coastal managers formulate the
procedures that will balance human actions with the needs of the environment (King,
1998).
Despite the complicated nature of the coastal zone, its natural dynamics and
processes do in theory lend themselves quite well to scientific enquiry using
geographical principles. The coast is very spatially and temporally dynamic, with
human and natural objects, features and landforms all affecting each other in some way
across space and through time. Data collected about these will inevitably have a geospatial component, and this data can be stored, manipulated and analysed within a GIS
to produce models of reality which aid in our understanding of the environment.
Both GIS and remote sensing have been quite widely used in coastal research.
However, although GIS is good for the integration, management and analysis of data, it
is not a source of raw data or method of primary data collection. Remote sensing, on the
other hand is. Its many advantages include up-to-date data provision, or data on
demand; data acquisition without field visits; early identification of environmental
problems; the ability of satellites to image large tracts of the Earth (allowing managers
to view whole coastal systems); near real-time and real-time imagery, and more detailed
monitoring of coastal landscapes, habitats and processes using higher resolution
imagery such as aerial photography and videography (King, 1998). However, perhaps
its greatest advantage is that the data delivered is usually in a form that most people will
instantaneously recognise as a ‘snap-shot’ of the Earth. It is this instinctive recognition
that makes remotely sensed imagery one of the best sources of geo-spatial data, because
it can be interpreted to a certain extent by most people, and this level of interpretation
yields valuable information.
Such an instantaneous, and possibly instinctive recognition and comprehension
of features shown on a remotely sensed image is what, in many cases, makes this source
of data far more valuable than a map, because maps are a more abstract representation
of reality, and not everyone can read maps. Yet, lack of exposure to remote sensing
beyond perhaps the occasional aerial photograph (be it oblique or vertical), limits the
use and application of remote sensing by the non-specialist, to environmental
management. Indeed, it is the relative familiarity of true colour or black and white aerial
photography above satellite imagery and other airborne sensors that prevents a more
inventive use of remote sensing, because people automatically think of aerial
photography as the best imagery for the job.
There are a number of reasons why this might be the case. Firstly, both true
colour and black and white aerial photography is more likely to be easily understood by
most people. Secondly, many people prefer to work, or perceive that it is easier to work
with hard copy photographs, rather than a digital copy on a PC or workstation; and
thirdly, the greater spatial resolution of aerial photography, which provides better detail