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Glaciers and Icebergs

Glaciers are an magnificent sight to see. Their enormous magnitude and brilliant colors can take your breath. Lets take a look at glaciers and the icebergs that calve off them.

Photo by Brenton Savikko

Glaciers are formed over many years of snowfall being packed down on the ice fields above them. Each year most glaciers recede due to a number of factors. The face of a glacier is exposed to the stresses of currents, tides, ocean swell, and the pressure of drifting pack ice. Calving occurs more often in tidewater glaciers, as they are subject to all of the factors mentioned above. When a glacier calves, it produces icebergs. Icebergs also erode and melt just as glaciers do. "When an iceberg has calved, it usually has little remaining strength in it's above-water portion which has warmed nearly to the melting point through percolation and refreezing. Much like the face of the glacier, the berg becomes weakened by ocean wave action. The high level of turbulence around the waterline of the berg increases the heat transport into the ice which cuts into it, making it even less stable." (Ice in the Ocean p. 258) Since an iceberg is 89% underwater, the process of erosion can make the berg very unsafe to be around. A change in the distribution of the weight of the berg can cause it to roll and move rapidly through the water.

Photos by Brenton Savikko