various in situ and airborne monitoring techniques to this project, none of them detected
the oil slicks to the extent or with the perspective of the satellite sensor.
Figure 2. Radarsat wide-swath synthetic aperture radar (SAR) image with 27 m resolution taken
over the Gulf of St. Lawrence on 31 July 1996 during the raising of the Irving Whale oil barge.
The white dots in the lower left are salvage barges and other vessels. The black lines are slicks
comprising a relatively small amount of oil which escaped during this successful salvage
operation. Image provided by and reprinted with the permission of the Canada Centre for Remote
Sensing. Original data © CSA 1996.
The barge was raised successfully, which was fortunate not only due to the
environmental disaster that would have ensued had the oil-laden barge broken-up, but
also because the satellite sensor which provided the only operational data would have
been of little benefit had the Canadian government been required to launch a major spill
response operation. This is because of the temporal resolution of satellite. The next
available wide-swath Radarsat image of the site was four days after the barge was
(successfully) raised. By then, the need for imagery had passed, thus averting a
situation in which the spatial extent of the slick could not be assessed using alternate
techniques. The project highlighted this sensor’s ability to detect surface slicks while
indicating that a constellation of such sensors is needed for low to mid-latitude
operations that require an effective revisit time on the order of daily to several times per
day. Such constellations of civilian radar sensors have since been proposed.
Geostationary satellites, which orbit the equator rather than near the poles, are
capable of fulfilling the temporal resolution requirements of dynamic environmental
processes and coastal operations. However, satellite sensors in geostationary orbit tend
to have relatively coarse spatial resolution (i.e. on the order of tens of kilometres),
which limits their application to coastal waters, cannot view very high latitudes, and are
limited in terms of types of available sensors. As a result, although they fulfill
meteorological requirements, geostationary Earth-observation satellite sensors are not
common components of coastal aquatic management programs.
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Whitehouse and Hutt
the oil slicks to the extent or with the perspective of the satellite sensor.
Figure 2. Radarsat wide-swath synthetic aperture radar (SAR) image with 27 m resolution taken
over the Gulf of St. Lawrence on 31 July 1996 during the raising of the Irving Whale oil barge.
The white dots in the lower left are salvage barges and other vessels. The black lines are slicks
comprising a relatively small amount of oil which escaped during this successful salvage
operation. Image provided by and reprinted with the permission of the Canada Centre for Remote
Sensing. Original data © CSA 1996.
The barge was raised successfully, which was fortunate not only due to the
environmental disaster that would have ensued had the oil-laden barge broken-up, but
also because the satellite sensor which provided the only operational data would have
been of little benefit had the Canadian government been required to launch a major spill
response operation. This is because of the temporal resolution of satellite. The next
available wide-swath Radarsat image of the site was four days after the barge was
(successfully) raised. By then, the need for imagery had passed, thus averting a
situation in which the spatial extent of the slick could not be assessed using alternate
techniques. The project highlighted this sensor’s ability to detect surface slicks while
indicating that a constellation of such sensors is needed for low to mid-latitude
operations that require an effective revisit time on the order of daily to several times per
day. Such constellations of civilian radar sensors have since been proposed.
Geostationary satellites, which orbit the equator rather than near the poles, are
capable of fulfilling the temporal resolution requirements of dynamic environmental
processes and coastal operations. However, satellite sensors in geostationary orbit tend
to have relatively coarse spatial resolution (i.e. on the order of tens of kilometres),
which limits their application to coastal waters, cannot view very high latitudes, and are
limited in terms of types of available sensors. As a result, although they fulfill
meteorological requirements, geostationary Earth-observation satellite sensors are not
common components of coastal aquatic management programs.
204
Whitehouse and Hutt