Monday, December 22, 2014

Nohokomeen Glacier

Last summer I had a nice view of the north side of Jack Mountain in the North Cascades.

Jack Mountain viewed from the south slope of Desolation Peak

Jack Mountain viewed from Ross Lake

Jack Mountain's north slope is covered by the Nohokomeen Glacier. There are small glaciers to the east of Jack Mountain, but this is the last of the larger glaciers that extend down to below 6,000 feet. The combination of the height of Jack Mountain (9,066 feet), its location downwind of the gap in the mountains created by the Skagit River and the north aspect of the slope have allowed the glacier to form and remain. Otherwise, this area of the North Cascades is not nearly as glaciated as the peaks further to the west. The range becomes progressively drier to the east and hence the number and size of glaciers this far east in the range is significantly less than areas to the west, and the elevations of glaciers becomes limited to higher peaks and ridges only. 

Blue line marks the current extent of the glacier 
The glacier terminus has retreated approximately 500 feet in elevation from its position when the topographic map was published

The available Google earth images suggest that the retreat since 1998 has been minimal.

Blue line marks the extent of the ice terminus in 1998 and is imposed on the 2013 image. 
The Nohokomeen Glacier is not among the the glaciers that have been routinely monitored and measured by the National Park.

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