HGIS: Territorial Sea Baseline

Coastal Zone Management

March, 1997

Investigation of Candidate Turning Points for Canada's
Territorial Sea Baseline on the South-East Baffin Island
and Northern Labrador Coast

Hunter and Associates was retained by the Canadian Hydrographic Services to identify candidate points for consideration as radius and baseline turning points for the establishment of Canada's Territorial Sea baseline on the remote south-east Baffin Island and northern Labrador coast lines. Work focussed on the search of library resources and the acquisition of appropriate existing aerial photography and satellite imagery for examination of headlands, islets and drying reefs over three specific areas:

Southeast Baffin Island, from Loks Land to Landy Franklin Island (Chart 7050)
Galvano Islands (Charts 4771 and 4773)
Orphan Island to Watchman Island (Chart 4763, 4764 and 4765)

During the progress of the work, the study area was extended northerly from the Galvano Islands to Labrador Reef.
The study proposed a chain of candidate turning points within and adjacent to the study areas. The chain, consisting of over 400 points, provides considerable redundancy, with additional nearby slightly inshore islets to back up the seaward selection. Among the report findings were:

LANDSAT TM satellite imagery processed with Bands 1, 2 and 3 provided the best evidence of islet and shoal waters previously intepreted from aerial photography. Higher band MSS and TM imagery was inferior.
Single date satellite images do not permit confident interpretation of small islet, reef and shoal features.
it is difficult to obtain ice, fog and cloud free imagery in the study area, with clear imagery limited to about once per decade.
Aerial photography interpretation combined with steroscopic examination provides superior images for interpretation of coastal features. This is true even for the small air photo scales (up to 1:100,000) and older photography avaible (1949 to 1963) on the Labrador and Baffin Coast.

The report recommended that the chain of candidate radius and baseline turning points be flown with GPS controlled high altitude colour aerial photography under ice free (<10%) conditions during July/August at a scale of 1:60,000.