Icebreaking Program

Technical Terms / Definition - Explication

ICE

Batture ice:

Ice floes that form on the upstream side of shoals and bridges when cold weather accompanies neap tides. The mass will freeze together causing an obstruction. Large sections can break off and drift downstream. Brash ice frozen together.

Brash ice:

Accumulation of ice made up of fragments not more than 2 m across.

Build up:

A build of ice. Can be formed by wind or current.

Canadian Ice Service (CIS):

A section of the Meteorological Service of Canada, within Environment Canada. They are the major supplier of ice information to CCG.

Fast ice:

Ice which forms and remains fast along the coast.

Fresh water:

Fresh water as opposed to salt water.

Ice-infested waters:

Waters that have any amount of ice on them.

Ice Service Specialists (ISS):

A CIS employee who is trained and qualified to make ice observations and reports. They work onboard ships and in ice offices and provide direct assistance to commanding officers and regional ice superintendents.

Ice jam:

An accumulation of broken ice caught in a narrow channel. Commonly occurs in rivers and near bridges and often results in flooding.

New ice:

Sea ice less than 10 cm thick.

Grey ice:

Sea ice 10-15 cm thick.

Grey-white ice:

Sea ice 15-30 cm thick.

First year ice:

Sea ice thicker than 30 cm.

Thick first year ice:

Sea ice thicker than 120 cm.

Old ice:

Ice that has survived at least one year’s melt. Found most often in the Arctic.

Ridges:

Ridges are formed when ice is under pressure.

OPERATIONS

At anchor:

A vessel secured by an anchor.

Beset:

A ship that is unable to move because of ice surrounding the vessel is beset.

Buoytender:

A vessel designed to place, and pick up buoys.

Convoy:

An escort of more than one vessel in a line.

Deployment:

A vessel is deployed when it has been assigned a task such as an escort.

Eastern Arctic Sealift:

The delivery of goods to northern settlements where there is no commercial service. In 2003, cargo was delivered to Kugaaruk (Pelly Bay) and Eureka.

Escort:

Direct assistance of an icebreaker to a vessel or vessels. The icebreaker will break a track that the escorted vessel will follow.

Flood control/Ice management:

Work done to minimize flooding due to ice jams. Includes monitoring ice conditions and water levels, preventing formation of ice jams, providing icebreaker services to facilitate ice flow during spring break-up, constructing and positioning ice booms and artificial ice islands.

Harbour breakout:

Breaking out the approaches and clearing ice from wharf faces of port terminals and facilities during the ice season, and the breaking out of harbours to facilitate ice clearance at the end of the ice season.

Ice boom:

A temporary structure constructed to encourage the formation of an ice cover outside the main shipping channel.

Icebreaker:

A ship specially designed and constructed for the purpose of assisting the passage of other ships through ice.

Light Icebreaker:

A vessel designed to work in lighter ice conditions, usually not far from shore. They are multi-tasked vessels. T1000

Medium Icebreaker:

A vessel designed to work in less severe ice conditions. These ships are multi-tasked. The vessels work as icebreakers in the winter and buoytenders in the summer. T1100

Heavy Icebreaker:

An icebreaker designed to work in severe ice conditions and extended periods of time in the Arctic. Also referred to as T1300 and T1200.

Ice information:

The provision of general ice information to vessels and other interested parties.

Ice island:

A permanent structure constructed to encourage the formation of an ice cover outside the main shipping channel.

Ice jam:

An accumulation of broken ice caught in a narrow channel. Commonly occurs in rivers and near bridges and often results in flooding.

Icebreaking Operations Data Information System (IODIS):

A data collection system used to gather statistics and produce reports.

Ice routing:

The provision of a specific route for vessel to follow through the easiest ice, reducing the need for escorts.

Ramming:

Attempting to break ice by repeatedly driving the ship as far forward as possible, backing the ship out and repeating the process.

Riparian:

People with riparian interests live next to the shore and are most affected by flooding.

Route assistance:

The direct assistance by icebreakers to vessels to allow movement through ice-infested waters. This is done by organizing convoys, escorting ships through ice-covered waters, freeing beset vessels and keeping shipping channels open.

Secured:

A vessel secured to the shore (i.e. at a wharf).

Sovereignty:

Maintaining sovereignty in the Canadian Arctic with such activities as guiding foreign vessels through Arctic waters.

Transit:

The time and distance it takes for a vessel to get from its present location to the location of the task.

REGULATIONS

Arctic shipping pollution prevention regulations (ASPPR):

The ASPPR govern some aspects of navigation through the Zone / Date system and AIRSS.

Arctic waters:

Canadian waters north of 60° N

Arctic Ice Regime Shipping System (AIRSS):

AIRSS combines information on the ice and a ship’s capability in ice to asses the potential for damage from the ice. When a ship uses this system it can travel outside the limitations set out in the zone/date system.

Arctic Waters Pollution Prevention Act (AWPPA):

An act to prevent pollution of areas of the Arctic waters adjacent to the mainland and islands of the Canadian Arctic.

Zone-date rules:

The arctic waters are divided into 16 shipping safety control zones, with a schedule of earliest and latest entry dates for each zone corresponding to specific categories of vessels.

OTHER

Envisat:

A European satellite that is used as a backup for ice information.

RADARSAT:

A Canadian satellite launched in 1995. It is still operating. It uses radar to acquire images. As a result cloud cover does not cause any problems. It is a major source of information to the Canadian Ice Service (CIS).

RADARSAT 2:

The planned successor to RADARSAT. It will be launched in the summer of 2007 on a Russian Soyuz vehicle from Kazakhstan.

SLAR - Side looking airborne radar:

A radar system onboard the Dash 8 ice reconnaissance aircraft