An ice information service, which will aid navigation on the North American Great Lakes, is being developed by the Untied States National Aeronautics and Space Administration (NASA) and the U.
An ice information service, which will aid navigation on the North American Great Lakes, is being developed by the Untied States National Aeronautics and Space Administration (NASA) and the U.S. Coast Guard.
Ice on the Grat Lakes, which straddle the United States-Canada border, limits the commercial shipping season to eight or nine months a year. This restricts millions of dollars worth of trade. The idea of the information service is to provide ice breakers and cargo vessels with a regular ice "guide", which would enable captains to head for any open water or choose a course through the thinnest ice.
The reporting system would use aircraft equipped with especial radar to locate and measure the thickness of the ice. These might later be supplanted by earth-orbiting satellites. The information gathered would be collated, and periodic ice maps could be issued to ships' captains.
Development of the service is being carried out by the Satellite Applications Section of NASA's Lewis Research Centre in Cleveland, Ohio. This winter, scientists from the centre flying over Lake Erie, Lake Huron, the Straits of MacKinac and Lake St. Clair, tested equipment for measuring the ice.
A Grumman Mohawk Army observation aircraft, equipped with radar capable of taking ice "photographs" through the clouds, was used in conjunction with a helicopter carrying radar to measure ice thickness, and a Douglas DC-3 aircraft operating an infrared thermal mapper to read ice surface temperatures. At the same time, samples of ice were collected on the aircraft flight paths to verify the airborne instrument readings.
SYNOPSIS: This Mohawk aircraft is taking pictures of ice on the Great Lakes, which straddle the United States-Canada border. Its mission is part of a programme to develop an ice information service for shipping on the lakes. The aircraft's special radar, which can see through clouds, is recording the ice distribution.
Scientists from the U.S. National Aeronautics and Space Administration's Lewis Research Centre, in Cleveland, Ohio, are working on the programme. Every year ice blocks millions of dollars worth of trade on the Great Lakes. Airborne instruments could be used to produce ice maps, which would tell ships' captains where the ice is weakest and where there is open water.
Samples of ice are also collected by the coast Guard along the Mohawk's flight path so that information recorded by the airborne instruments can be compared. The aircraft's radar can measure the surface temperature of the ice, as well as its thickness and distribution.
When the ice information service has been set up, it is hoped eventually to gather the necessary readings by satellite. The service would also enable the U.S. Coast Guard ice-breakers to operate more efficiently in keeping sea lanes open as long as possible during the winter.