North Cascade glaciers

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North Cascade Glacier Climate Project 2013 Field Report

The 2013 winter season provided close to average snowpack in the North Cascades as indicated by the average SWE at SNOtel stations in the range. The summer melt season has proved to be long, warm and dry. The May-August mean temperature at the station closest to a glacier, Lyman Lake, has been tied for the 2nd warmest in the last 25 years with 2009 and only 2004 warmer. The summer has lacked record periods of warmth and has featured sustained warm temperatures and higher than average humidity, reducing the number of nights when the glacier surface has frozen. The average minimum temperatures at Lyman Lake are the highest in the last 25 years for July and August. The humidity was the strikingly high during our field season, note diagram from a Cliff Mass article on the topic. The net result will be significant negative glacier mass balances in the North Cascades. There is one month left in the melt season most glaciers are close to an equilibrium balance already.

The field team included Stewart Willis and Matt Holland, Western Washington University, Jill Pelto, U of Maine, Ben Pelto, UMass,-Amherst, Jezra Beaulieu and Oliver Grah, Nooksack Indian Tribe research scientists And Tom Hammond, North Cascade Conservation Council. Alan Kearney, Photographer worked with us for the first week capturing time lapse imagery of our work.

After a month of perfect summer weather we arrived to a foggy and wet conditions on the Columbia Glacier. The Columbia Glacier terminus was exposed and has retreated 85 m since 1990. The glacier had a substantial area of blue beginning 200 m above the terminus and extending along the western side of the basin for 400 m. The area of blue ice on August 1 was 50,000 square meters, by Aug. 21 the area had expanded to 200,000 square meters, the shift of the 2013 winter snowline during this period indicates a melt of m during the three weeks.


The Lower Curtis Glacier terminus was exposed early in the summer resulting in a continued retreat of 20 m since 2011, the area of thick seraced terminus lost since 1990 has been 60,000 square meters. The lateral retreat and terminus retreat since 1990 are both in the 125-150 meter range depending on location.
We spent a week observing ablation and resulting glacier runoff on Sholes Glacier. With Oliver Grah and Jezra Beaulieu who work for the water resources section of the Nooksack Indian Tribe we emplaced a stream gage right below Sholes Glacier and one on Bagley Creek which is snowmelt dominated. With the water level gages in we all began work on a rating curve for the Sholes Glacier site directly measuring discharge on 14 occasions, kayak socks helped reduce the impact of cold water. Average ablation during the week was 8.25 cm/day of snowpack or 5 cm of water, discharge measurements identified a mean of 5.2 cm/day of from the glacier during this period. The agreement between ablation and discharge was a nice result. Discharge became notably more turbid after 1 pm, peaking in turbidity around 5 pm. Of equal interest was the change in snowcovered area. On July 19th a Landsat image indicated 100% snowcover for Sholes Glacier. On Aug. 4th our surface measurements indicates a blue ice area of 12,500 square meters, which is also evident in a Landsat image from that day. By Aug. 20th a satellite image indicates that the blue ice area had expanded to an area of square meters. This coincided with the area where snowdepth was observed to be less than 1.2 m on Aug.4. This represents a volume loss of 592,000 cubic meters of water in 16 days.
We measured the mass balance on Rainbow and Sholes Glacier during this period. The snowpack was poor on both, especially above 1900 meters on Rainbow Glacier. Typical depths are over 5-6 m, this year 3.75-4.5 m. The poor snow depths were also noted on the Easton Glacier above 2000 m in crevasse stratigraphy measurements. Each crevasse is approached probing to ensure it is safe and then assessed to make sure the crevasse is vertically walled, this enables a safe but also accurate measure. In some cases layers from mulitple years can be assessed. IN the Lynch Glacier crevasse the 2013 layer will be lost to melt before end of the summer. 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. ice worm 2013

ice worm 821upelto team
Ben in his 9th year, Jill her 5th year and Mauri 30th year of glacier work in the North Cascades

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28th Field Season of the North Cascade Glacier Climate Project 8-1 to 8-20

During the interval of 8-1 to 8-20 there will be no blog updates, we will be in the field for the entire period. This is the 28th consecutive year we will monitoring the terminus behavior and mass balance of these glaciers identifying how they respond to climate change. In these 28 years all the glaciers have retreated significantly they have lost 20% of their volume and two of the glaciers we monitored every year have disappeared.
If you are in need of glacier observations, please take a look back at the index of 100+ posts to date
Or look at the video footage below from the 2010 field season and the 2009 field season

North Cascades Glacier Documentary Promo 2010 from Cory Kelley on Vimeo.


2009 field season video

We begin the field season on Columbia Glacier near Monte Cristo, WA.
We will then head north to the Lower Curtis Glacier on Mount Shuksan. A traverse west will takes us to Sholes and Rainbow Glacier on the ne side of Mount Baker.

We will then drive around Mount Baker and examine the Easton, Deming, Squak, Talum and Boulder Glaciers on the south and east side of Mount Baker.

We then head to Cache Col Glacier near Cascade Pass and finally south to Mount Daniels for Ice Worm, Daniels and Lynch Glacierto finish the field season. It was a historically cool and wet spring and the glaciers still have a thick blanket of snowcover. How thick is what we will be measuring one glacier at a time.

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Rainbow Glacier Mass Balance

In 2010 at the end of a four day period of cool rainy weather we hiked into to our base camp on Ptarmigan Ridge to measure the mass balance of the Rainbow Glacier on Mount Baker in the North Cascades of Washington for the 27th consecutive year. Below is a view of Rainbow Glacier as we approach it. This is a valley glacier that begins on the slopes of Mount Baker at 2200 m and descends to a terminus that is often avalanche covered at 1350 m. The year proved to be the most variable in terms of glacier mass balance of any of our 27 years. Assessing the mass balance requires melting the extent and depth of snowpack on the glacier. We had a chance to measure the snow depth in 121 locations using crevasse stratigraphy and probing. The below image has all of the measurement locations, blue dots, and the rough contours of mass balance marking the snowline in green-blue, the 1 meter of snowpack water equivalent (swe) in purple and the 2 m of swe in blue. Glacier margin is in orange-brown.. The initial field assessment of mass balance for the Rainbow Glacier in 2010 was +0.81 m. At this time the significant melt season is at an end, new snow is projected for tomorrow 9/23. The average over the previous 26 years has been -0.40 m/year. Of the ten glaciers we monitor there was a split with six having negative balances and four positive, the variation is unusual. The probe is a half inch diameter steel rod that is easily driven through the snowpack until the hard icy layer marking last years summer surface is reached. This can either be bare glacier ice or the firn from the previous year. In either case it cannot be penetrated. The second means is to lower a tape measure down the wall of a vertically sided crevasse. This provides a two dimensional measure and view of snow depth versus the point measurement of probing. By late summer the density of the snowpack is uniform in the North Cascades. We survey the blue ice regions using a GPS to map the boundaries. Melting is assessed by observing the progressive ablation of snow and ice. On Rainbow Glacier snowpack was normal below 1800 m, where probing is dominantly used. The snowline was at 1450 m in early August and had risen to 1600 m by late September. Above 1600 m the snowpack increased very rapidly this year from 1.5 m at 1800 m to 5.5 m at 2100 m. This reflects the unusually warm winter that led to a dearth of snow below 1800 m by winters end. Above this elevation several winter events that were rain below were snow. Than melting was well below normal in the summer of 2010. Again spring snow storms retarded melt above 1800 m, while those were rain events below this elevation.
Crevasse stratigraphy was the dominant tool of measuring snowpack on the Rainbow up to is divide with Mazama Glacier. Navigating these crevasses takes considerable care using the snow probe as a crevasse probe. . The area of bare glacier ice is riven by some large streams, which are also the focus of annual observation. T The terminus this summer was buried in snow from an avalanche, as was the case last year. In 2007 the terminus was fully exposed and we could measure the retreat at 450 m in the last 25 years. This glacier’s mass balance history follows that of the other northwestern North American glaciers which also is right in line with global mass balance. All data is from the WGMS. One of the best parts of this location is the gorgeous campsite we use for a base camp. It is above the glacier so we have to hike uphill at the end of the day. . his area is noted for its mountain goats as well which we count annually. We will complete a final analysis in the next month and report this data to the World Glacier Monitoring Service.

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North Cascade Glacier Climate Project 27th field season 2010 starts Aug. 1

For the next three weeks I will be in the North Cascades of Washington visiting and measuring snowpack, snow melt and area change on North Cascade glaciers. There will be no new posts here during this period. Though you can take a look at the film documentary crews site travelling with us. Our main task is assessing glacier mass balance on 10 glaciers which are then reported to the World Glacier Monitoring Service (WGMS). We measure the snowpack by probing through it to the previous summer’s impenetrable surface, due to melting and refreezing or being blue glacier ice. The other means is examining snow depth in a crevasse using the evident stratigraphy. We monitor the snow melt and reset stakes in the glacier to monitor the snow melt as well. We also measure changes in surface elevation and margins of the glacier. We will report back shortly after our return on the status of these climate sensitive glaciers.