Almost all icebergs found along the east coast of Canada originate from the glaciers of west Greenland. Most of the active glaciers along the west Greenland coast are located between Smith Sound and Disko Bay. Melville Bay, from Cape York to Upernavik, is a major source of icebergs; it is estimated that 19 active glaciers produce 10,000 icebergs annually. A second area of importance is Northeast Bay, including Karrats and Umanak Fiords, where about 5,000-8,000 icebergs are calved from 10 major glaciers each year. Disko Bay also produces a small number of icebergs from two glaciers.
Photograph of a pinnacled iceberg (Photo courtesy of Canadian Ice Service) & Photograph of an ice island (Photo courtesy of Canadian Ice Service).
A few Canadian glaciers on Baffin, Bylot, Devon, Coburg, and southern Ellesmere Islands calve icebergs, but only in small numbers. The annual production of icebergs from Canadian glaciers is estimated to be about 150. Total annual production of icebergs in Baffin Bay is estimated to be 25,000-30,000, although some estimates are as high as 40,000. More than 90 per cent of the icebergs come from west Greenland glaciers.
The size of icebergs calved varies from growler size (about 20 square metres with 1 metre above water) to icebergs 1 kilometres long and over 200 metres high. The height-to-draught ratio of an iceberg varies from 1:1 to 1:3 for pinnacle icebergs, to 1:5 for blocky, steep-sided tabular icebergs. A study of icebergs in Davis Strait suggested that a ratio of 1:4 was a good approximation for estimating iceberg size. If the height of an iceberg is 100 metres it would not be unreasonable to expect a draught of 300 to 500 metres. As a result of their substantial draught, even smaller icebergs frequently become grounded in coastal waters and on shoals.
Source: Ice Navigation in Canadian Waters, Chapter 3: Ice Climatology and Environmental Conditions, Government of Canada - https://www.ccg-gcc.gc.ca/publications/icebreaking-deglacage/ice-navigation-glaces/page04-eng.html
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