Shape, Size and Colour

Iceberg Shape

ShapeImageAverage height to draft1 ratio
TabularPhoto of tabular iceberg
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Photo of a non-tabular iceberg
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Photo of a domed icerberg
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Photo of a pinnacle iceberg
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Photo of a wedge icerberg
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Photo of a drydock iceberg
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Photo of a blocky iceberg
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Iceberg Size

Iceberg typeIceberg SizeHeight above sea surface (meters)Length (meters)Weight (Megatons)
Growler Size comparison of a growler to a personless than 1 metreless than 5 metres0.001
Bergy Bit Size comparison of a bergy bit to a garage1 metre to less than 5 metres5 metres to less than 15 metres> 0.01
Small Berg Size comparison of a small berg to a house5 metres to 15 metres15 metres to 60 metres>0.1
Medium Berg Size comparison of a medium berg to a yacht16 metres to 45 metres61 metres to 120 metres2.0
Large Berg Size comparison of a large berg to an arena46 metres to 75 metres121 metres to 200 metres10.0
Very Large Berg Size comparison of a very large berg to a large buildingGreater than 75 metresGreater than 200 metresGreater than 10.0 metres


Iceberg Colour

Icebergs are mostly white because the ice is full of tiny air bubbles. The bubble surfaces reflect white light giving the iceberg an overall white appearance. Often, white icebergs will have bluish streaks running through them. This blue tinted ice has no air bubbles to reflect white light and gets its blue colour from the same light phenomenon that tints the sky.

White ice is created inside of a glacier. As snow falls over thousands of years, it piles up and compacts the snow under it. During this compaction process, any air bubbles between the snowflakes are trapped. Finally, after the snow and air bubbles have been compacted over many years, they become the white ice that icebergs come from.

Blue, bubble free ice is made when the ice is still part of the glacier. Melt water fills crevasses formed in the glacier as it creeps over land and quickly freezes without any air bubbles forming.

Occasionally airborne dust or dirt eroded from land ends up on the glacier surface eventually forming a noticeably darkened brown or black layer within the ice of a floating iceberg. This brown or black layer has nothing to do with bubbles. The ice is just dirty!

Diagram of the bubbles in the ice reflecting white light (from the sun) giving the iceberg its white colour.


Footnote 1

Draft: vertical distance between the waterline and the bottom of the iceberg.

Return to footnote 1

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