Tough Summer for North Cascades Glaciers
September 3, 2013
Dr. Mauri Pelto of the North Cascade Glacier Climate Project has completed his 30th annual survey of glacier mass and conditions in the rugged region near the Canadian border in Northern Washington State.
The North Cascades area is breathtaking – the glacier conditions, heartbreaking.
His video above illustrates a little appreciated truth about the science of climate change – that it comes not from models or computers, but from millions of accumulated data points, acquired through slow, disciplined, and (trust me on this) physically demanding effort on the part of researchers willing to spend lifetimes in that pursuit. This boots-on-the-ice type of science is what I hope my readers will appreciate more and more through this blog and the accompanying videos.
Easton Glacier had a terminus that was fully exposed by the start of August. The terminus slope has thinned markedly in the last three years as retreat has continued. The retreat of Easton Glacier has averaged 10 m/year from 2009-2013. This year the retreat will exceed that with two months of exposure. The Deming Glacier retreat has been exceptional over the last 12 months with at least 30 m of retreat.
The snowline on Easton Glacier was at 1850 m on Aug. 10th. By the end of August the snowline had risen to 1980 m, where snow depths had been 1.5 m three weeks previous. The mass balance of Sholes, Rainbow and Easton Glacier will all be close to – 1 meters water equivalent, that is losing a slice of glacier 1.1-1.2 m thick. Mount Daniels had the best snowpack of any location in the North Cascades. On the small and dying Ice Worm Glacier ablation and runoff were assessed simultaneously. The expansion of the area where 2013 has all melted expanded rapidly from 8/13 to 8/21. The glaciers lower section had is often avalanche buried, this year the snowpack was gone on much of the lower section. However, snowpack averaged 1.7 m across the entire glacier on August 14th. With daily ablation of 7-8 cm/day this will be gone by early September. This will lead to a substantial negative mass balance this year. Lynch and Daniels Glacier both had limited exposed blue ice and firn, and snowpack values that were slightly above average. Both glaciers will have small negative mass balances this year. On Lynch Glacier a large crevasse at exposed the retained snowpack of the last three years, from 2010-2012 5 m of firn remains.
Hope to follow up with more from Dr. Pelto in the future.
My videos documenting last year’s trip accompanying Dr. Pelto and team are below.
Below, Dr. Pelto shows the extent of mass loss at Easton Glacier in the last 200 years or so. Somewhat disorienting wobble in the video from YouTube – I said “yes” when their bot offered to “improve” the vid. Sorry for that.
More extended piece on the same trip: