Tag: columbia Glacier retreat

North Cascade Glacier 2022 Initial Observations-39th Field Season

On By mspeltoIn North Cascade Glaciers2 Comments

field team 1

2022 North Cascade Glacier Climate Project Field Team

Science Director: Mauri S. Pelto, mspelto@nichols.edu
Art Director: Jill Pelto, pelto.jill@gmail.com

For the 39th consecutive summer we were in the field to measure and communicate the impact of climate change on North Cascade glaciers. We completed detailed measurements on 10 glaciers, three of which are part of the World Glacier Monitoring Service reference glacier network (42 glaciers globally), which have 30+ consecutive years of mass balance observations. NCGCP was founded in 1983 to identify and communicate the response of North Cascade glaciers to regional climate change. We are a fieldwork-based project with a focus on measuring changes in mass balance, glacier runoff, and terminus behavior. The project has an interdisciplinary scope — collaborating with a range of natural scientists, artists, journalists, and conservationists.

This winter snowpack remained below average until a late season surge from April into May.  Snowpack was 90% of the mean (1977-2021) on April 1% and 110% of the mean on May 10.  The month of May and June had below normal temperatures leading to an above average glacier snow cover as June ended. July and August were exceptionally warm at Heather Meadows  (4200 feet) average July and August maximum temperature is 19.2 C, this year 20 days reached or exceeded 5 C above this temperature in July and August 2022. At Stevens Pass (4000 feet) average July and August maximum temperature is 21.4 C, this year 24 days reached or exceeded 5 C above the temperature in July and August 2022. The average July-August temperature at the Stevens Pass and Lyman Lake sites was the highest since records began in 1990.

The result is that glacier snowcover rapidly melted during the July-August period, which is resulting in significant mass losses for North Cascade glaciers that continue to thin, retreat and lose volume. The climate stress is evident on the glaciers, but also in the alpine vegetation and alpine aquatic ecosystems.

Field team backpacking around Blanca Lake at our first field site.

Columbia Glacier with the 1984 terminus position, note the glacier profile now descends from west side (left) to east side (right) of the glacier. The glacier has retreated 270 m since 1984. Note steep tongue extending across entire cirque valley in 1988 lower image.

Columbia Glacier indicating the avalanche fans that now provide most of the accumulation to the glacier at the blue arrows. The yellow arrows indicate avalanche slopes that are no longer key feeders resulting in marginal thinning and recession. These locations or reduced avalanching have resulted from the source area slopes having lost their perennial snow and ice, which must be filled each winter before a slide can occur. Snowpack in the avalanche fans exceeds 3 m, while outside of the avalanche fans averaged 1.8 m on Aug. 1-2, 2022.

Jill Sketching Blanca Lake and Troublesome Creek draining from Columbia Glacier.

Braided stream issuing from the the rapidly retreating and thinning Sholes Glacier on the north flank of Mount Baker. Retreat since 2015 has been 90 m, with 225 m since 1984.

Snow depth measurements  in meters on Rainbow Glacier using crevasse stratigraphy, adjacent Park and Mazama Glacier drain the upper part of Mount Baker. Average depth at 2000 m was 5.25 m, 3.15 m water equivalent. The terminus of the glacier continues to retreat rapidly, but was buried by avalanche debris at the time of our survey in 2022.

Alia Khan’s Western Washington University team assessing a red algae zone on Rainbow Glacier, we led them through the icefall to this location, where they sample impurities on the glacier surface and relate that to remote sensing products.

Jill’s sketch of Rainbow Glacier and Mount Baker from trail above Lake Ann.

Lower Curtis Glacier indicating recession since 1985. The glacier has thinned considerably in the lower section since the 2003 image below.

Navigating through the icefall region on Lower Curtis Glacier where we are mapping snow pack depth and crevasse depth. 

Deglaciated terrain since 1990 below Easton Glacier. We mapped this at 0.18 square kilometers in 2022.

We have observed crevasse depths for a decade and have seen both their number and depth decline in icefalls on Easton and Lower Curtis Glacier due to glacier thinning and reduced velocity. Deepest crevasses are at the top of the convex slope change, 25-30 m deep.

Claire Giordano painting Easton Glacier crevasse ‘blues’ at top of lowest icefall.

Ascending into Easton Icefall with five annual layers exposed on serac.

Snow depth assessment in specific crevasse at 2500 on Easton Glacier. No snow was retained here in 2021. Avergage depth in 2020 in this region 5.5 m, 4.75 m in 2022.

Easton Glacier has retreated 470 m from 1990-2022. Above is 2022 and below is 2003 image.

Ice Worm Glacier on Mount Daniel was fully snowcovered. We completed a grid of 72 snow depth measurements with a mean of 2.1 m in depth. The glacier continues to recede faster on its upper margin than at the terminus.

Descending onto Lynch Glacier, which had an accumulation area ratio of 83% in mid-August. Average snow depth 2.5 m.

Probing snow depth and surveying blue ice margin on Lynch Glacier.

Daniel Glacier was fully snowcovered in mid-August. Consistent snow depths of 1.8-2.5 m.

Jill’s field watercolor and colored pencil. This piece was done below the small Iceworm Glacier, on Mt. Daniel. It looks out towards the prominent Cathedral rock and Alpine Lakes Wilderness. Jill really enjoyed making this piece — to start she sketched the landscape, and then temporarily moved in front of the purple penstemon and the pale elmira flowers to capture them in the foreground. A while after she began painting, the wind dropped, and the mosquitoes arrived in force. Jill had to stop painting for the evening and went back to camp. Because Jill then finished at home, it was fun to add some more detail to this piece.

In the vicinity of Peggy’s Pond near our Mount Daniel base camp are a dozen shallow ponds, 10-20 cm are average that typically endure through the hatch of tadpoles in late August or early September. The primary inhabitants are frogs (Rana Cascadea) and their tadpoles. In 2022 despite a wet spring and early summer that had the ponds brimming with water, right above, tadpoles were observed, where typically there are several hundred, and the frog numbers were ~50% of usual. This followed the dried beds of these ponds in 2021, at left.  Maybe this is in part why mosquitoes were swarming here.

In 2021 below Easton Glacier we noted a number of alpine plants that had emerged just before or during the record June heat wave, had been dessicated/cooked by the heat in this are of relatively barren volcanic rock. Most notably lupine. This year in the same region we noted that ~30% of the lupine had failed to develop by August 2022, despite a cool wet spring. In contrast the evergreen alpine plants in the same area penstemon, saxifrage, pink and white heather, and partridge-foot all were fine.

Columbia Glacier, Alberta 3 km Retreat 1986-2015

On By mspeltoIn Canada glacier retreat

Comparison of Columbia Glacier, which is the glacier flowing into the lake at top in 1986 and 2015 Landsat images. The red arrow is the 1986 terminus, yellow arrow the 2015 terminus position and purple arrow the tributary.

The Columbia Glacier drains the northwest side of Columbia Icefield into the Athabasca River in Alberta. The glacier in 1964 was 8.5 km long, by 1980 9.5 km long and in 2015 6.2 km long. The glacier drops rapidly from the plateau area over a major ice fall from 2400-1950 m.  The icefall leads to the creation of a series of ogives during the 1960-1990 period. Ogives are annual wave bulges that form at the base of an icefall due to differential seasonal flow velocity. Ommaney (2002) noted that the glacier advanced over one kilometer from 1966 to 1980 the glacier completely filled the large proglacial lake that now exists. By 1986 retreat had again opened the lake. Tennant and Menounos (2013) examined changes in the Columbia Icefield 1919-2009 and found a mean retreat of 1150 m and mean thinning of 49 m for glaciers of the icefield.  They noted that the fastest rate of loss on Columbia Icefield glaciers from 1919-2009 was during the 2000-2009 period.

In 1986 Landsat imagery the lake is 1000 m long. A 2004 Google Earth image indicates a step in elevation that is 500 m from the terminus.  Glacier elevation lags the basal elevation change; hence the end of the lake is between 500 and 1000 m from the 2004 terminus. By 2015 the lake is 4000 m long indicating a 3000 meter retreat from 1986-2015.  The rate of retreat has been less since 2004, 300 m, as the glacier approaches the upper limit of the lake basin.  When the glacier terminus retreats to this step, the lake will no longer enhance retreat via calving and retreat rates will diminish.  A further change is noted in the absence of ogives at the base of the icefall. As the icefall has narrowed and slowed the result has been a cessation of this process. The purple arrow indicates a tributary that joined the glacier below the icefall in 1986 that now has a separate terminus. The current terminus is still active with crevassing near the active front.  The snowline in both August 2015 and July 2016 is close to 2800 m.  A more detailed look at the 2016 mass balance conditions in the region just west of the glacier suggest Columbia Glacier had a more negative balance than in the Columbia River basin. With time left in the ablation season the snowline is at too high of an elevation to sustain strong flow through the icefall.  The retreat is more extensive than the more famous and oft visited glaciers draining east from the icefield Athabasca Glacier and Saskatchewan Glacier.

A 2004 image of the glacier indicating the ogive band, and step where the upper limit of the lake likely occurs. 

Sentinel image indicating the snowline at 2750-2800 m m on July 27, 2016. 

31 years of observations on Retreating Columbia Glacier, Washington

On By mspeltoIn climate change glacier retreat, glacier climate change, Glacier Observations1 Comment

For the last 31 years the first week of August has found me on the Columbia Glacier in the North Cascades of Washington. Annual pictures of the changing conditions from 1984 to 2014 are illustrated in the time lapse video below. This is the lowest elevation large glacier in the North Cascades. Columbia Glacier occupies a deep cirque above Blanca Lake and ranging in altitude from 1400 meters to 1700 meters. Kyes, Monte Cristo and Columbia Peak surround the glacier with summits 700 meters above the glacier. The glacier is the beneficiary of heavy orographic lifting over the surrounding peaks, and heavy avalanching off the same peaks. This winter has been the lowest year for snowpack in the North Cascades in the 32 years we have worked here.  Below is a comparison from August 1, 2011 with Blanca Lake below the glacier still frozen and a beautiful scene on April 4, 2015 with the lake not frozen taken by Karen K. Wang.  The winter in the region was unusually warm, but not as dry as in California; however, in the snowmelt and glacier fed river basins summer runoff will be low this year.

 

Blanca Lake Aug. 1, 2011 on left and April 4, 2015 on right (Karen K. Wang, www.karenkwang.com)
Blanca Lake Aug. 1, 2011 on left,  and April 4, 2015 on right (Karen K. Wang, www.karenkwang.com)

Over the last 31 years the annual mass balance measurements indicate the glacier has lost 14 meters of thickness. Given the average thickness of the glacier of close to 75 meters in 1984 this represents a 20% loss in glacier volume. During the same period the glacier has retreated 135 meters, 8% of its length. Most of the loss of volume of this glacier has been through thinning not retreat.  To survive a glacier must have a persistent and consistent accumulation zone (Pelto, 2010).  On Columbia Glacier in 1998, 2001, 2003, 2004, 2005, 2009 and 2013 limited snowpack was retained, resulting in thinning even on upper part of the glacier.  This thinning of the upper glacier indicates the lack of a persistent accumulation zone such as in 2005, note the exposed annual ice and firn layers green arrows, this indicates the lack of retained accumulation in recent years.  This indicates the glacier is in disequilibrium and cannot survive. Mapping of the glacier from the terminus to the head indicates a similar thinning along the entire length of the glacier.  The overall mass balance loss parallels that of the globe and other North Cascade glaciers in the last three decades.

columbia accumulation zone 2005

2005 Accumulation zone of Columbia Glacier

 

On left cumulative mass balance of Columbia Glacier compared to the WGMS global record and other North Cascade glaciers. On right change in surface elevation along the glacier from terminus to head indicating a 14-15 m thinning on average.
On left cumulative mass balance of Columbia Glacier compared to the WGMS global record and other North Cascade glaciers. On right change in surface elevation along the glacier from terminus to head indicating a 14-15 m thinning on average.

A comparison of images from  1986, 2007 and 2013 photograph provide a view of  glacier change at the terminus. The blue arrows indicate moraines that the glacier was in contact with in 1986, and now are 100 meters from the glacier. The green arrow indicates the glacier active ice margin in 1986 and again that same location in 2007 now well off the glacier. The red arrow indicates the same location in terms of GPS measurements, this had been in the midst of the glacier near the top of the first main slope in 1986. In 2007 this location is at the edge of the glacier in a swale. The changes are more pronounced in 2013 as the terminus slope continues to decrease. The low snowpack in 2015 on the glacier in March, 2-3 m versus 6-8 m, will lead to considerable changes in the terminus this summer, that we will assess.

1986 Terminus Columbia Glacier

columbia 2007 comp

2007 Terminus Columbia Glacier

columbia glacier2013 comp.

2013 Terminus Columbia Glacier

Jill Pelto painted the glacier as it was in 2009 (top) and then what the area would like without the glacier in the future, at least 50 years in the future (middle), and Jill at the sketching location (bottom), turned 180 degrees to view Blanca Lake. The lake is colored by the glacier flour from Columbia Glacier to the gorgeous shade of jade.

Clearly the area will still be beautiful and we will gain two new alpine lakes with the loss of the glacier. After making over 200 measurements in 2010 we completed a mass balance map of the glacier as we do each year. This summer we will be back again for the 32nd annual checkup.  There will be likely be record low snowpack, comparable to 2005 the worst year from 1984-2014.

2010 Mass Balance map of Columbia Glacier

Columbia Glacier Past, Present and Future

On By mspeltoIn Uncategorized1 Comment

For the last 27 years the first week of August has found me on the Columbia Glacier in the North Cascades of Washington. Annual visit pictures up to 2008 can be seen at bottom of post.

This is the lowest elevation large glacier in the North Cascades. Columbia Glacier occupies a deep cirque above Blanca Lake and ranging in altitude from 1400 meters to 1700 meters. Kyes, Monte Cristo and Columbia Peak surround the glacier with summits 700 meters above the glacier. The glacier is the beneficiary of heavy orographic lifting over the surrounding peaks, and heavy avalanching off the same peaks. Over the last twenty seven years the annual mass balance measurements indicate the glacier has lost 14 meters of thickness. Given the average thickness of the glacier of close to 75 meters in 1984 this represents a 20% loss in glacier volume. During the same period the glacier has retreated 135 meters, 8% of its length. Most of the loss of volume of this glacier has been through thinning not retreat. The glacier remains thick, but cannot survive current climate, which has left the glacier without any snowpack by the end of the summer in five of the last 10 years. This lack of persistence is the sign of a glacier than cannot survive. We can look at the past of the Milk Lake Glacier near Glacier Peak in 1988, 30 miles northeast of Columbia Glacier, and the present of Milk Lake without the glacier. The green arrow points to the forming lake filled with by both icebergs and the still evident glacier. The upper margin of the glacier is indicated by the red arrow. The lake in 2009 still is a nice jade green from glacier erosion. This lake will slowly become more azure in color as no new glacier sediment is added. In the same respect we can look at the past and present of Columbia Glacier comparing a 1986 and 2010 photograph. The blue arrows indicate moraines that the glacier was in contact with in 1986, and now are 100 meters from the glacier. The green arrow indicates the glacier active ice margin in 1986 and again that same location in 2007 now well off the glacier. The red arrow indicates the same location in terms of GPS measurements, this had been in the midst of the glacier near the top of the first main slope in 1986. In 2007 this location is at the edge of the glacier in a swale.. To look to the future Jill Pelto, (see marvelous destiny blog) my daughter painted the glacier as it was in 2009 (top) and then what the area would like without the glacier in the future, at least 50 years in the future (middle), and Jill at the sketching location (bottom), turned 180 degrees to view Blanca Lake. The lake is colored by the glacier flour from Columbia Glacier to the gorgeous shade of jade. Clearly the area will still be beautiful and we will gain two new alpine lakes with the loss of the glacier. After making over 200 measurements in 2010 we completed a mass balance map of the glacier. This summer we will be back again for the 28th annual checkup.