206
10.3.2
Canada
C. BERTOIA, J. FALKINGHAM, F. FETTERER
Canadian ice reconnaissance can trace its roots back to the 1920S when aircraft first
flew over the ice-covered waters of the Arctic. The Royal Canadian Air Force maintained
responsibility for monitoring ice conditions over the next 25 years, occasionally working in conjunction with the US Navy and the Canadian Department of Transport. In
1954, the responsibility for ice services in Canada was transferred to the Meteorological Branch of the Department of Transport. This organization oversaw the ice services
required for the development of ports, trade, fishing and other resources in areas
throughout the Canadian Arctic, ranging from the St. Lawrence River to Nova Scotia
and Newfoundland. Ice reconnaissance services were also provided for Arctic probes
such as those by the tanker/icebreaker SS Manhattan in 1969/1970 and eeGS Louis St.
Laurent in 1972. When the Meteorological Branch was moved into the Department of
the Environment at the Atmospheric Environment Service in 1971, the Canadian Ice
Service's main data source continued to be aerial ice reconnaissance. DC-4s gave way
to Lockheed L-188 Electras in the 1970S. In 1972, the ice service awarded a long-term
contract for the service of two Electra L-188-C aircraft dedicated to ice reconnaissance
missions. A new technological era began with the installation of the first side looking
airborne radar (SLAR) sensor aboard the Electra C-GNDZ. By 1989, the Electras had
been retired in favor of a de Havilland Dash-7 and a Challenger jet. In 1995, the Challenger was released from service as satellite data became sufficiently reliable.
The Canadian Ice Service (CIS) considers its area of geographic responsibility to
include the Great Lakes, the st. Lawrence River to the Gulf of st. Lawrence, the eastern
Canadian seaboard, Hudson Bay, and the Canadian Arctic Archipelago from western
Greenland to the Beaufort Sea. Ice products focus on areas where ships are operating,
in order to support safe and efficient maritime operations in sea ice. Thus, winter areas
of support are found along the Canadian east coast and the Great Lakes. During the
summer, focus shifts to the high Arctic regions (Fig. 2).
Radar has been used for operational ice reconnaissance since the early 1960s when
search radars were installed on ice reconnaissance aircraft of the Canadian Ice Service.
These radars were forward-looking, nonimaging, sweep radars. While these radars had
limited capability to determine ice parameters, they were useful for the accurate measurement of range and bearing to the ice edge. The opportunity to employ an imaging
radar was presented when the US Coast Guard offered to loan a Motorola APS-94D
SLAR, recently returned from military use in Vietnam, to Canada in 1978. With an
extensive airborne ice reconnaissance program already in place, Canada was seeking a
means to extend the range of visual observations in order to make this type of reconnaissance more cost-effective.
The APS-94 SLAR boasted a ground range of 100 km and an azimuth resolution of
37 m. Because it was a real-aperture system, the range resolution increased from 37 m
at the near edge of the swath to about 400 m at the far range. Operating in X -band with
very shallow incidence angles, the SLAR was so successful in mapping ice conditions
that a second unit was added in 1980. In 1984, the Motorola SLAR was replaced by the
CAL-200 SLAR, an instrument that remains in operation in 1996.
Following on the heels of an extensive research program at the Canada Centre for
Remote Sensing, airborne SAR was introduced for ice reconnaissance in Canada in the
10.3.2
Canada
C. BERTOIA, J. FALKINGHAM, F. FETTERER
Canadian ice reconnaissance can trace its roots back to the 1920S when aircraft first
flew over the ice-covered waters of the Arctic. The Royal Canadian Air Force maintained
responsibility for monitoring ice conditions over the next 25 years, occasionally working in conjunction with the US Navy and the Canadian Department of Transport. In
1954, the responsibility for ice services in Canada was transferred to the Meteorological Branch of the Department of Transport. This organization oversaw the ice services
required for the development of ports, trade, fishing and other resources in areas
throughout the Canadian Arctic, ranging from the St. Lawrence River to Nova Scotia
and Newfoundland. Ice reconnaissance services were also provided for Arctic probes
such as those by the tanker/icebreaker SS Manhattan in 1969/1970 and eeGS Louis St.
Laurent in 1972. When the Meteorological Branch was moved into the Department of
the Environment at the Atmospheric Environment Service in 1971, the Canadian Ice
Service's main data source continued to be aerial ice reconnaissance. DC-4s gave way
to Lockheed L-188 Electras in the 1970S. In 1972, the ice service awarded a long-term
contract for the service of two Electra L-188-C aircraft dedicated to ice reconnaissance
missions. A new technological era began with the installation of the first side looking
airborne radar (SLAR) sensor aboard the Electra C-GNDZ. By 1989, the Electras had
been retired in favor of a de Havilland Dash-7 and a Challenger jet. In 1995, the Challenger was released from service as satellite data became sufficiently reliable.
The Canadian Ice Service (CIS) considers its area of geographic responsibility to
include the Great Lakes, the st. Lawrence River to the Gulf of st. Lawrence, the eastern
Canadian seaboard, Hudson Bay, and the Canadian Arctic Archipelago from western
Greenland to the Beaufort Sea. Ice products focus on areas where ships are operating,
in order to support safe and efficient maritime operations in sea ice. Thus, winter areas
of support are found along the Canadian east coast and the Great Lakes. During the
summer, focus shifts to the high Arctic regions (Fig. 2).
Radar has been used for operational ice reconnaissance since the early 1960s when
search radars were installed on ice reconnaissance aircraft of the Canadian Ice Service.
These radars were forward-looking, nonimaging, sweep radars. While these radars had
limited capability to determine ice parameters, they were useful for the accurate measurement of range and bearing to the ice edge. The opportunity to employ an imaging
radar was presented when the US Coast Guard offered to loan a Motorola APS-94D
SLAR, recently returned from military use in Vietnam, to Canada in 1978. With an
extensive airborne ice reconnaissance program already in place, Canada was seeking a
means to extend the range of visual observations in order to make this type of reconnaissance more cost-effective.
The APS-94 SLAR boasted a ground range of 100 km and an azimuth resolution of
37 m. Because it was a real-aperture system, the range resolution increased from 37 m
at the near edge of the swath to about 400 m at the far range. Operating in X -band with
very shallow incidence angles, the SLAR was so successful in mapping ice conditions
that a second unit was added in 1980. In 1984, the Motorola SLAR was replaced by the
CAL-200 SLAR, an instrument that remains in operation in 1996.
Following on the heels of an extensive research program at the Canada Centre for
Remote Sensing, airborne SAR was introduced for ice reconnaissance in Canada in the