Geology Reference
In-Depth Information
Figure 11.5 The Challenger jet aircraft used as a platform for the synthetic aperture radar STAR‐2 system to
provide sea ice reconnaissance service for the Canadian Ice Branch. The radar antenna is mounted forward
of the wing, underneath the fuselage, and covered by a large fiberglass dome (black bubble in the picture)
[ Sutton , 1991].
a new perspective of the extent and dynamics of sea ice.
The Very High Resolution Radiometer (VHRR) data
were introduced to the Ice Centre in 1972 followed by the
Advanced Very High Resolution Radiometer (AVHRR)
data in the fall of 1978. Although the utilization of this
data was limited by daylight and the cloud conditions, the
Ice Centre was quick to embrace their use.
A remarkable milestone in sea ice data acquisition was
the introduction of the space‐borne SAR imagery data in
1992. The first stream of SAR data was received from the
European satellite ERS‐1 during the period 1992-1995.
The data were assessed for their utilization in the ice moni-
toring program through a pilot demonstration project
[ Shokr , 1994; Shokr et al ., 1996]. Later, SAR data from the
Canadian satellite Radarsat‐1 became the prime source
of  information for data analysis and ice charts products
when CIS started to receive it regularly in 1996. That was
replaced with Radarsat-2 since its commissioning in 2008
(the satellite was launched in December 2007). It is worth
mentioning that Radarsat-1 was decommissioned on 29
March 2013. The CIS uses nearly 4000 Radarsat‐2 scenes
per year in its operational ice monitoring program. It is the
largest user of Radarsat data, followed by the Canadian
Department of National Defense. As for the ice data
analysis, it suffices to mention another milestone that has
contributed significantly to upgrading the functions of
CIS. That was the Expanded Ice Information Services
Program (EIISP) in 1983. The program aimed at enhanc-
ing the ice analysis and forecast products to meet growing
demands. It provided $77 million in capital for computer
and communication equipment (including buying a
Dash‐7 aircraft with an SLAR system). It also provided $7
million for an expansion of the sea ice information pro-
gram to support year‐round Arctic navigation. Most of
the equipment was delivered in 1986. By that time three
major systems were completed: (1) the Iceberg Analysis
and Prediction System (BAPS) intended to provide com-
puter‐assisted iceberg analysis and forecasts; (2) the Ice
Data Integration and Analysis System (IDIAS), which
was a computer‐based system designed to assist ice ana-
lysts in their visual analysis of remote sensing imagery
data and production of ice charts, and (3) the Ice Services
Communications System (ICCS), which was designed to
manage and direct internal and external data sources to
the appropriate computing facilities and users.
In 1995, the IDIAS was replaced by a more advanced
GIS‐based system called the Ice Service Integrated
System (ISIS). It employs an ERDAS imagine package of
remote sensing image analysis. It is being used to produce
a variety of sea ice products including image analysis and
daily and weekly ice charts (see next section). The system
allows the ice analyst to view a satellite image, subjec-
tively create polygons of uniformly distributed ice attrib-
utes (ice types and concentrations), and assign attributes
to each polygon. The system then coverts this informa-
tion to shape files with the coded attributes. In the future
ISIS will be replaced by an ArcGIS‐based system (instead
of ERDAS), called POLARIS. Currently, CIS operate
three systems: (1) ISIS for the production of ice charts
and bulletins as well as the analysis of all available sources
of remote sensing, shipboard, and ground data, (2) the
Canadian Ice Data Analysis System (CIDAS) for archive
and analysis of ice data, and (3) the Ice‐Vu system for
visualization of all Ice Service products from the field
and the icebreakers.
11.2. operational sea ice programs
and products
As mentioned before, the responsibility of sea ice mon-
itoring, modeling, and forecasting in Canada is mandated
to the Canadian Ice Service of Environment Canada.
However, they share activities with other branches of the
same department as well as the Canadian Coast Guard
of the Department of Fisheries and Oceans (DFO). The
CIS uses a number of data sources (mainly from satellite
remote sensing) to collect and analyze information about
ice conditions in Canadian waters during its growth and
disintegration. Ice analysts in CIS analyze satellite images
and field observations visually, assemble all ancillary
data, and integrate all information to produce a number
of operational charts and bulletins. Six sea ice products
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