Navigating Arctic Waterways Using GIS
Water transit is vital to Canada's economy. Each year, ships face many challenges traveling the waters of the Arctic Ocean, the Gulf of St. Lawrence, and the Labrador Sea. Ice floes and icebergs obstruct shipping lanes, delaying transit and creating hazards for both the ships and those on board. These environmental conditions have caused some of history's more famous maritime disasters--most notably the Titanic, which sank off the coast of Newfoundland in April 1912.
Consequently, the Canadian government places a premium on studying and understanding the dynamics of sea ice formation and drift. The Ice and Marine Services Branch (IMSB), a branch of the Meteorological Service of Canada, provides the Canadian Coast Guard (CCG) and the United States Coast Guard, through partnership with the National Ice Center in Washington, with accurate and timely reports of sea ice conditions for the east coast of Canada and the Canadian Arctic. Headquartered in Ottawa, the purpose of the IMSB is to improve maritime navigation in Canadian and international waters and provide crucial environmental information of pack ice in Canada's northernmost regions.
To fulfill its mandate, the IMSB depends on integrated GIS and supporting information technologies for the acquisition and efficient processing of data from satellites, airborne radars, ice/weather models, and other data sources.
Using GIS, the IMSB annually analyzes more than 10,000 satellite images, conducts in excess of 20 million square kilometers of airborne reconnaissance, and receives hundreds of ship and shore ice reports.
IMSB provides timely and accurate ice information for day-to-day marine decision support in Canadian waters. The acquisition, processing, and integration of real-time data are essential for the generation of daily charts and reports. Since 1995, the Ice Service Integrated System (ISIS) has successfully processed significant volumes of diverse digital data within the fixed constraints of a daily production and delivery schedule. The ISIS is built on ArcInfo and ArcView from Esri; ERDAS IMAGINE software from ERDAS, Inc.; and Oracle enterprise databases. During the design phase, it was determined that ArcInfo and IMAGINE offered the best combination of customization and performance. Integrated support for coverage and shapefile formats within IMAGINE allowed for efficient transfers of vector data into ArcInfo for completion of the chart products.
"ISIS satisfies the IMSB's requirement fora system that is cost effective to implement, reliable in a production environment, and flexible and scalable enough to adapt to new data sources, products, platforms, and evolving Business requirements," says Awtar Koonar, chief, Information Technology Division, Canadian Ice and Marine Service, Environment Canada.
A typical day at the IMSB involves the real-time acquisition and analysis of data; integration of GIS, image, raster, and alphanumeric data; product generation; and the dissemination of text, chart, and image products to its clients. All products are also available to clients, partners, and the public.
The ISIS Metadata Repository is composed of a relational database management system and a database of Content Standard for Digital Geospatial Metadata from the U.S. Federal Geographic Data Committee. It is intended as a resource that provides access to geospatial metadata in a consistent fashion that can be searched efficiently and extensively.
The method of accessing the ISIS Metadata Repository is the Geospatial Metadata Browser, built on ArcView. The browser presents the users with a consistent view of the repository, and the "footprint" of the data can be superimposed on basemaps, which allows the user to see the geographic extent of the data object, thereby helping to present the context of the data.
The Ice Analysis Subsystem is the high-end, fully functional ISIS workstation that provides access to all data referenced by the Metadata Repository. Custom tools have been developed for sorting, displaying, and analyzing data to generate products such as charts (image analysis, daily navigation analysis, and monthly composites) and bulletins. The subsystem enables analysts to enhance and analyze imagery and then annotate with text and line objects to reveal ice characteristics. Based on high-availability UNIX servers and Windows 2000 platforms, the subsystem makes extensive use of ArcInfo, ArcView, and ERDAS IMAGINE.
The Field Decision Support Subsystem is the low-end ICE-VU workstation that is deployed on CCG vessels, in remote ice operation offices in CCG regions, on board aircraft, and at the Ice Forecast Centre. ICE-VU workstations were designed specifically as marine decision support applications and provide CCG vessels with the capability to receive real-time synthetic aperture radar (SAR)/side-looking airborne radar (SLAR) data or to download compressed MrSID imagery and GIS products from the Ice Forecast Centre.
This summer, three high-speed satellite direct links will be installed on major CCG ships that will enable these ships to transfer imagery, GIS, and other data sets cost effectively with improved performance. This will significantly improve the amount ofinformation available to navigators who are often restricted by unreliable analog connections.
A new ISIS subsystem is currently in the concept stage. This is the OnBoard Analysis Subsystem, and it is intended to have capabilities between the high-end ISIS and low-end ICE-VU Ice Analysis Subsystems. Visual data entry will be based on pen computers, and data analysis will be provided by the Ice Analysis Subsystem. This will allow the user to interpret SAR/SLAR imagery in near real-time, generate an analysis enhanced by other sensor data, and then downlink the product directly to ships or satellite broadcast stations.
Another area in which the IMSB will concentrate in the future is archiving its data. It is responsible for an extensive archive of the Canadian maritime cryosphere, specifically sea ice, lake ice, and icebergs. This information is an integral component for monitoring global climate variation since the cryosphere is especially sensitive to minute changes in environmental conditions.
"Currently the IMSB is saturated with various charts, images, and analyses, and we would like to put all this together into a state-of-the-art archive accessed through ArcSDE and ArcIMS," says Koonar. "The geodatabase will provide us with capabilities for managing versions of the data for 'what-if' scenario modeling and tracking historical changes. ArcSDE and the geodatabase will provide us with a centralized mechanism for managing and sharing geographic information."
To provide interaction with the new archive, the IMSB intends to provide a MapObjects software-based browser. This tool will allow the user to query and retrieve information not only from a focused operational catalog but also a large GIS-enabled data warehouse of cryosphere resources.
Contact Awtar Koonar, Canadian Ice and Marine Services Branch (e-mail: firstname.lastname@example.org), or visit ice-glaces.ec.gc.ca for more information. A version of this article recently appeared in ArcNorth News (Vol. 5 No. 2, 2002), published by Esri Canada.