It takes both cold conditions and wet weather to create a glacier. The Olympic Mountains, Alaska, New Zealand, and Patagonia, among other places, all have highly active glaciers. About 4.5 meters of precipitation falls on Blue Glacier every year. Much of this comes during the winter and accumulates as snow. More rain and snow land on Blue Glacier than on any other glacier, or even any other place, in the continental United States.

Snow falls on all areas of Blue Glacier from roughly October to May; but if you were to measure the snowfall after a large storm you would find varying depths at different locations. Winter winds frequently exceed 145 kilometers per hour on the glacier causing the snow to drift and redistribute. Fifty percent more snow, for example, accumulates in the relatively sheltered cirque above the icefall than at the adjacent but exposed snowdome,even though the elevations are similar.

Not all of Blue GlacierŐs precipitation is snow and counts as accumulation; throughout the year it also rains on the glacier. Two thirds of this rain remains liquid and helps to melt the snow base while the remaining third freezes directly to the glacier. A big storm in the autumn is more likely to be snow and add to the accumulation amount while spring precipitation is often in the form of rain and can increase melting. Thus the yearly depth of new snow accumulation depends on not only how much precipitation the glacier receives, but also on what time of year it falls.



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Benjamin Drummond 2002