Climate and Ice Cover

Lying entirely north of the Arctic Circle, Baffin Bay has a cold and dry polar climate. Annual average temperatures range from -12°C (10°F) in the northwest to -5°C (23°F) in the southeast. Precipitation is low; however, fog is a common occurrence in coastal areas and near openings in the ice cover. Along the Greenland coast, offshore katabatic winds (cold air flowing off inland mountains or icefields) are frequent. The usual track for cyclones is from west to east just south of Davis Strait; however, cyclones occasionally follow troughs north into the bay.

Baffin Bay is covered by sea ice from October through May. Ice cover in Baffin Bay is almost entirely first-year ice (less than 1.6 m thick), although some multiyear ice enters the bay through Smith, Jones, and Lancaster Sounds. Because of wind and ocean currents, sea ice may pile up in places to a thickness of 3-4 m (10-13 ft). Off the southwestern coast of Greenland, ice cover tends to be reduced because of the warm ocean currents. At the northern end of the bay, in Smith, Jones, and Lancaster Sounds, episodic openings in the ice (called polynyas) form under the influence of winds and upwelling warm water. Collectively, these polynyas form what is called the North Water. The North Water is known to influence climate for hundreds of kilometers in all directions, and the large amount of heat pumped into the atmosphere through the polynyas sometimes triggers the formation of local cyclones.

A stream of icebergs passes through Baffin Bay, originating primarily from glaciers in northwestern Greenland. The typical track for the icebergs is north along the Greenland coast and south with the Baffin Current, after which the bergs join the Labrador Current and move out into the North Atlantic. Between 10,000 and 15,000 icebergs pass through Baffin Bay annually, creating a significant hazard for shipping.

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