Cascade Pass Area Loses Two Glaciers

On December 17, 2023March 3, 2024 By mspeltoIn North Cascade Glaciers1 Comment

The Triplets and Cascade Peak glacier in GLIMS glacier viewer with the red outlines of the 1958 and 2015 margins and the black dot indicating they are now extinct.

In a 1993 Washington Geology article I noted that “In the Cascade Pass area two small glaciers in Torment Basin and two beneath the Triplets Peak and Cascade Peak have altitude ranges of less than 150 m. These glaciers in 1985, 1987 and 1992 were entirely in the ablation zone if present conditions persists they will disappear.” This is an update on the glaciers below The Triplets and Cascade Peak. The threshold for a glacier to exist in terms of area is typically 50,000 m² or 10,000 m², there must also be motion which is increasingly rare as area drops below 50,000 m² (Leigh et al 2019). Motion is typically determined by active crevassing, which does not include relict crevasses reaching bedrock (Fountain et al 2023). To survive a glacier must have a persistent accumulation zone, the lack of this leads to thinning of the glacier even in its upper accumulation area (Pelto, 2010).

The Triplets and Cascade Peak glacier with plentiful active crevassing in 1986 image I took from near Cascade Pass.

The Triplets and Cascade Peak glacier with significant retained snowcover in 1990 image I took from near Cascade Pass.

In 1986 I first walked on the two glaciers below The Triplets and Cascade Peak. They were crevassed glaciers fed on north facing benches below the peaks providing good radiational shading and fed by avalanches. The glaciers are also steep enough to shed avalanches. In 1992 these two glaciers did not retain significant snowpack and we noticed some crevasses within 50 m of the ice front reaching bedrock. Of more import was that several sections of glacier with bedrock reaching crevasses had slid detaching from the glacier on the steep smooth bedrock glacier bed.This process of melt driven thinning leading to detachment of small glacier sections is what prompted me to think these glaciers would not last. This type of detachment is evident in the 1998 Google Earth image, lower right of Cascade Peak Glacier.

The Triplets and Cascade Peak glacier with limited snowcover on Triplets glacier even in early August 1992. We were on route to the glacier when I took this picture.

Crevasse on Triplet Glacier that reaches bedrock near terminus in 1996.

The Triplets and Cascade Peak glacier with active crevassing in 1998 Google Earth image (yellow arrows). Some of these crevasses reached bedrock and led to detachments, note lower right on Cascade Peak glacier.

The Triplets and Cascade Peak glacier with active crevassing in 2003 with developing separation between east and west sections at yellow arrows.

The Triplets and Cascade Peak glacier with active crevassing only on Cascade Peak glacier in 2016 Google Earth image (yellow arrow).

In Sept 2023 The Triplets is now six fragments Cascade Peak glacier is three fragments. Image from Wyatt Mullen, who shares spectacular images on Instagram daily.

From 2003-2005 each summer these two glaciers failed to retain much snowpack and continued to thin and lose area. The Global Land Ice Measurements from Space (GLIMS) assessed the The Triplets and Cascade Peak glaciers with an areas of respectively 55,000 m² and 60,000 m², respectively this area was updated with a 2015 area assessment of 70,000 m² and 32,000 m² respectively. In 2019, 2021, 2022 and 2023 glaciers in the North Cascades experienced a sequence of years that left most glaciers in the range largely snow free for the last 4-6 weeks of the melt season leading to exceptional mass loss and consequently area loss. The area of the largest contiguous area of ice of the two glaciers declined from 51,000 m² and 31,000 m² in 2019, to 37,000 m² and 26,000 m² in 2021 and 18,000 m² and 15,000 m² in 2023. By 2023 neither glacier exhibited active crevassing as both approached the lower threshold for glacier existence. Thirty years after my initial assessment both The Triplets and Cascade Peak glaciers no longer exist. This is shown in the GLIMS glacier viewer which illustrates extinct glaciers as black dots. These two are in the list of 34 extinct glaciers in the North Cascades that I have measured since 1984 that are now gone, and are in this GLIMS extinct glacier layer. The sustained mass balance loss of North Cascade glaciers is what is leading to significant volume declines of all glaciers and loss of glaciers that were thin (Pelto, 2018).

The Triplets and Cascade Peak glacier in August 2019 Sentinel false color image. Area of The Triplets glacier =51,000 m²: Cascade Peak glacier=31,000 m²

The Triplets and Cascade Peak glacier in August 2021 Sentinel false color image. Area of The Triplets glacier =37,000 m²: Cascade Peak glacier=26,000 m²

The Triplets and Cascade Peak glacier in August 2023 Sentinel false color image. Area of The Triplets glacier =18,000 m²: Cascade Peak glacier=15,000 m²

From Mount Hood to Mount Robson Extremely Limited 2023 Snowcover Retained

Written by Ben Pelto, Jill Pelto and Mauri Pelto

Field Sketch of Ice Worm Glacier from Aug. 13, 2023 on photograph of glacier. (Jill Pelto)

It was July 5, 1981 and Juneau meteorologist Brad Coleman had just informed us that Juneau had experienced one of its warmest least snowy winter ever. I was with the Juneau Icefield Research Program and we were headed up to the icefield the next day, it would be my first visit to a glacier. I was looking forward to plentiful summer skiing and now was concerned there would be limited snow. This worry proved unfounded, as once on the icefield, we stayed above 1000 m, and it was all snow, allowing me to ski 500 km in the next several weeks. From that summer through 2000, I continued to spend the majority of my time working on glaciers every August skiing whether in Alaska or in the North Cascade Range, Washington. Alpine glaciers need to maintain at 55%+ snowcover right to the end of the summer to maintain equilibrium. Hence, skiing should be plentiful. However, in 2003 I gave up skiing on glaciers during our August North Cascade field seasons, the snow had become too limited and patchy. During the last decade the percentage of snowcover has been consistently low, with the 2021-2023 period setting the record for persistent snowcover deficits in the North Cascacdes, but also throughout the Pacific Northwest from Mount Robson, BC to Mount Shasta CA. This sequence of difficult years for glaciers had led to the end for quite a few. -Mauri Pelto

I have spent 15 years with the NCGCP most years snow remains only at higher elevations or in large avalanche fans, with a couple of years having deep snowpack and lack of heat waves has led to a good year for the glaciers. And now years like 2015, 2021 and 2023 where there is so little snow that walking on the glaciers is almost a different landscape. Every feature is exposed, debris cover is piled up, and new or changed water features like melt channels or ponds emerge. In August 2023 it was most starkly seen on Mt. Daniel, on the eastern, drier side of the North Cascades. It was my first year seeing the loss of a glacier: the Iceworm Glacier. A remnant ice patch remains, but there are no longer any active features such as crevasses. It was also my first time seeing the very steep Daniel Glacier with essentially no snow. Navigating across bare ice on a 35+ degree slope for very few measurements had our whole team questioning how long it would be worth our effort. Some of my favorite moments of my 14 other seasons are glissading (or skiing with your hiking boots) down the steep slopes of Daniels. You can carve turns and do quick stops, and you can get down the glacier in about a quarter of the time you climb up. It’s always an exhilarating and rewarding way to end the season. This year the descent was difficult one firm crampon step at a time. I clung onto one fun glissade on the adjacent Lynch Glacier. In that moment I needed to enjoy what I could, and after the season I needed to feel the loss of a place that has defined a piece of my life.

Here we focus on this lack of snowcover we observed in the field and in satellite images from Mount Hood, OR to Mount Robson BC in August and Septemeber 2023. This combined with 2021-2023 has redefined many glaciers, making it clear how many cannot survive even current climate. We developed a forecast model of alpine glacier survival, published in 2010 that indicated significant accumulation zone thinning and/or lack of consistent accumulation zone are indicators of a glacier that cannot survive. The glaciers below on some of the highest peaks in OR, WA and BC are failing this metric in 2023.

At the end of August 2023 on the north side of Mount Hood, OR; Sandy Glacier and Ladd Glacier are so dirty looking in this Sentinel image that it is hard to discern that they are glaciers, both have limited patches of retained snow from the winter of 2023. Coe Glacier has three pockets of snow remaining from last winter covering close to 30% of the glacier.

Across the Columbia River on Mount Adams, WA Wilson and Rusk Glacier are both over 90% bare firn and ice, with some snow on the upper margin above 2800 m where avalanche deposits endured.

On the south slope of Mount Rainier, WA South Tahoma Glacier and Success Glacier lost all of their snowcover. There are a few patches of snow left on Kautz Glacier. The snowcover becomes more consistent at 3500 m, higher than can sustain most of the glaciers.

Halfway between Mount Rainier and Glacier Peak is the Mount Daniel/Hinman area where glaciers are in rapid collapse. This includes Ice Worm Glacier on the east slope of Mount Daniel, which lost all of its snowcover in 203 (above) and Daniels Glacier that only has 5% snowcover in mid-August 2023 (below)

Foss Glacier on the northeast slope of Mount Hinman looks like a bug that splats on your windishield with wings/limbs in all directions, this will lead to rapid fragmentation.

Closer to Glacier Peak is Columbia Glacier, below Kyes, Monte Cristo and Columbia Peak. The view down the accumulation zone indicates a lack of snow or firn where there should be 2+ m of snowpack in early August.

On Glacier Peak Ptarmigan Glacier has separated into and east and west part and had no retained snow. Kennedy, Vista and Ermine Glacier had 10-20% retained snowcover on 9-15-2023 mostly in a band at 2500 m. Yellow arrows indicate terminus locations when I first visited these glaciers 40 years ago.

Easton Glacier is on the south/southwest side of Mt. Baker. The upper part of the glacier is a patchwork of ice, firn and snow, with new rock areas emerging even high on the glacier in August 2023. The difference with 2022 is evident. Two new waterfalls appeared in 2023 due to the extensive thinning and retreat at the terminus., yellow arrows. These are also depicted in the field sketch by Jill Pelto below.

Near Whistler, BC, the Garibaldi Neve (Icefield) showed little remaining snow in mid-September. Snow only clings high on Mount Garibaldi above 2200 m or 7200 ft.

Small glaciers across the region are losing all traces of seasonal and multi-year snow and are transitioning from active glaciers to remnant ice patches. The Stadium Glacier near Squamish British Columbia is one example of this. Photo by Ben Pelto.

The Conrad Glacier on the boundary of Bugaboo Provincial Park in British Columbia showing extensive bare ice and limited snow cover. The dark grey areas surrounding the white snow is firn, or multi-year snow, now exposed. The area covered by firn is important to glacier health. Firn that remains on a glacier becomes glacier ice and can retain meltwater. Areas of bare ice behave like a parking lot, nearly all water that reaches glacier ice leaves the glacier as runoff. The area of glaciers covered by firn is dramatically decreasing in the region. Pelto et al. (2019) found that 58% of the Conrad Glacier was covered by multi-year firn, a quick visual scan here shows that that number has declined to roughly 30-40%.

Wildfire smoke darkens the sky and ice as Alexandre Bevington, Jacob Bailey and Margot Pelto stand on the Conrad Glacier in August 2018. Photo by Ben Pelto.

Coleman Glacier is on the east flank of Mount Robson. In 2018 the terminus is in a small lake with the snow covering 25% of the glacier. By 2023 the glacier has retreated 400 increasing the lake size. The snowcovered area is less than 10% of the entire glacier and is restricted to regions above 2500 m.

The above images of snow free and nearly snow free glaciers is a sight that has until the last decade been very rare. It is now becoming a typical event. The glacier response has been rapid, profoundly changing most and leading to the end of some.

Collapse of the Glacier Complex on Mount Daniel-Hinman, Washington

On August 24, 2023April 18, 2024 By mspeltoIn North Cascade Glaciers

Jill Pelto Sketches the demise of Ice Worm Glacier August 13, 2023.

In 1984, as the North Cascade Glacier Climate Project began, the largest concentration of glaciers between Mount Rainier and Glacier Peak was on Mount Daniel-Hinman; Daniels, Foss, Hinman, Ice Worm and Lynch Glacier. Hence, I felt these glaciers were worth monitoring. Now in August 2023, we just finished our 40th annual survey of these glaciers and they have had their worst year yet in terms of mass loss. Each year we ascend the Cathedral Rock trail, hike passed Peggy’s Pond and set up camp to observe the glaciers. The rapid mass loss builds on the last two year leading to dramatic thinning and area loss. Ice Worm Glacier and Hinman Glacier are no longer glaciers. Pelto (2010) developed a forecast model that identified a glacier that retreats and thins not just at the terminus but even on the upper glacier, does not have a consistent accumulation zone and cannot survive. Foss Glacier may not survive the summer. Daniels Glacier is rapidly shrinking. Only Lynch Glacier remains active. This is the story of the glacier’s decline and the impact.

In 1958 these five glaciers had a combined area of 3.8 km². In 1984 the area was 3.2 km², in 2009 the area had declined to 1.5 km², and 0.8 km² in 2023. This is an 80% decline since 1958 and ~a 50% decline since 2009. This area loss is driven by mass balance losses. We measure the mass balance annually on Daniels, Ice Worm and Lynch Glacier from 1984-2023, and on Foss Glacier 1984-2005. From 1984-2022 mean annual balance averaged -0.6 m w.e., a cumulative loss of 21.3 m w.e.. The mass balance losses have driven the reduction in glacier area. In recent years, the mass losses have been consistent and greater than the long term mean at –1.20 m w.e. annually. This summer is not complete but will finish close to -3 m in a single year.

On Ice Worm Glacier the retreat of the top of the glacier has been faster than the terminus of the glacier. This summer we observed a dozen holes that reached the bottom of the glacier 4-6 m below, indicating how thin the ice is. There is no movement, the size and thickness are too low to generate future movement, hence this is no longer a glacier. A glacier is a body of snow and ice that is moving, this requires a persistent thickness of 20-30 m, which is typically associated with snow/ice areas of ~50,000 m² or larger. As a glacier becomes thinner or smaller than this movement will not be sustained.

Hinman Glacier crossed that threshold either in summer 2021 or 2022 with no patch of ice exceeding 30,000 m². This had been the largest glacier in the region, but had no avalanche accumulation to supplement.

Daniels Glacier has a long terminus section that leads to rapid area loss with even a retreat of 20 m. This year the lowest 20% of the glacier is quite thin and much of this likely will melt out in the coming month. For the first time ever in our 40 years of observation there is no significant retained snow in early August. Glacier length has been reduced by 60% since our monitoring began.

Lynch Glacier had filled Pea Soup Lake basin until the late 1970’s. After its rapid retreat exposed this beautiful new lake, the glacier retreated slowly at its terminus. However, the entire western third of the glacier is nearly gone, even up to the ridge top. This illustrates again that retreat does not always of the terminus.

Foss Glacier was a large slope glacier filling the northeast face of Mount Hinman in the 1980s. By 2005, the glacier had retreated exposing two new alpine lakes and was clearly on the path of Hinman Glacier. Fragmentation began in 2015 and has accelerated during the 2021-2023 period. This will no longer be a glacier either later this year or next year.

Daniels Glacier in 2023, less than 50% remaining from 1984. The glacier terminus has retreated 700 m, with the longest glacier section now at 450 m. Daniels Glacier on Aug. 14 2022 and Aug. 14 2023. In 2022 a late start to summer preserved snowpack, but summer conditions did not end until Octs. 21. (Jill Pelto, photographs).

Daniels Glacier in 1990. This blue ice tongue is now completely gone.

Daniels Glacier indicating change from 1984 to 2010.

Ice Worm Glacier in 2013 area 0.08 km², 33% less than in 1984.

Ice Worm Glacier in 2023 area 0.04 km², 67% decline since 1984 and 50% since 2013.

Ice Worm Glacier comparison Aug. 13 2022 and Aug. 13, 2023. Jill Pelto photographs.

Lynch Glacier in 2023 with west side melted out.

Foss Glacier covered the northeast slope of Mount Hinman in 1988 and by 2015 was only 50% of the 1984 size.

Foss Glacier in 2023, it is not some thin rapidly fragmenting sections of ice covering 0.14 km².

Hinman Glacier in 1988 four separate ice masses.

Hinman Glacier from 1.3 km² in 1958 to 0.04 km² in 2022.

The three largest glaciers on these mountains in 1958 fed the SkykomishRiver supplying 1.5 to 2 m³/sec durng the summer melt season (Pelto, 2011). This summer we measured melt on these glaciers yielding 25-30% of this level. The result has been declining flow during late summer low flow periods in the Skykomish River resulting in higher water temperatures. Daniels and Ice Worm Glacier feed the Cle Elum River, whose reservoir is an important resource for irrigation in the Yakima Basin. A key threshold of in-stream flow levels considered insufficient to maintain short term survival of fish stocks is below 10% of the mean annual flow. For the Skykomish River at the USGS Gold Bar site 10% of mean annual flow is 14 m³s^-1. In the Skykomish River from 1958-2021 there were 344 melt season days with discharge below 14 m³s^-1. Of these only 3 occurred before 1985, and 70% have occurred since 2000. Of more concern for aquatic life is the occurrence of extended periods of low flow. From 1929-2023 in the Skykomish River basin there have been 14 years where streamflow dropped below 14 m³s^-1 for 10 consecutive days during the melt season, 1986, 1987, 1992, 1998, 2003, 2005, 2006, 2007, 2015, 2017, 2019, 2021, 2022 and 2023. All years occurring during our annual monitoring project, 6 in the last decade. In 2022 this occurred beginning on Sept. 9 after stream temperatures had declined from elevated levels. In 2023 flow dropped below this threshold on Aug. 13 and remains below this threshold coinciding with high water temperatures.

The Skykomish River was listed as impaired for temperature in a 2008 303(d) listing. Several segments of the Skykomish River as well as its tributaries consistently exceed water quality temperature standards (King et al 2013). During select summer periods from 2001-2006, temperature monitoring in the Skykomish River at Monroe indicated that the average 7-Day maximum frequently exceeded the 16°C criteria between July and September in 2001-2006 (King et al 2013).

A water temperature sensor became operational in early July 2022 at the USGS Gold Bar site. The temperature exceeded 18^oC for the first time on July 27. It surpassed 18^oC diurnally on most days from July 27-September 7, 37 of 42 days. The TMDL for the Skykomish River indicates the maximum temperature should not exceed 16^oC for 7 consecutive days. In 2022 16^oC was exceeded continuously from July 26th-August 4th, August 14th-August 28th, and August 29th-September 4th. In 2023 the 16°C threshold was exceeded from July 28-Aug. 21. The reduced late summer glacier flow has reduced the ability of these ice masses to buffer both temperature and discharge during droughts. This same process has been observed in the Nooksack River (Pelto et al 2022).

The impact of glacier loss is not the only reason for declining streamflow, but it is a significant reason. The loss of glacier ice is thus causing issues that extend all the way to Puget Sound or the Columbia River system.

Skykomish River Basin, GB=Gold Bar, blue arrows indicate glaciers 1=Columbia, 2=Hinman, 3=Foss and 4=Lynch.

Temperature and discharge observations at the USGS Gold Bar site in late summer 2022.

Temperature and discharge observations at the USGS Gold Bar site in late summer 2023.

40th Field Season of North Cascade Glacier Climate Project Underway

On July 29, 2023April 19, 2024 By mspeltoIn North Cascade Glaciers

Illustration by Megan Pelto of key numbers behind what it takes to undertake a 40 year field study on glaciers.

For the 40^th consecutive summer the North Cascade Glacier Climate Project is heading into the field to measure and communicate the impact of climate change on North Cascade glaciers. This field season follows the 2021 and 2022 seasons that featured a historic heat wave and periods of extended warm weather. The heat led to a greater exposure of bare ice on glaciers, particularly at higher elevations. For ice surfaces with a higher albedo and greater density the observed melt rates are 7-9 cm per day water equivalent during warm weather events vs 4-6 for snow surfaces. This led to substantial mass losses on North Cascade glacier for the two years of -2.5 m. Winter snowpack in the North Cascades in 2023 was 80-90% of normal on April 1 and May 1.

Science objectives: We will complete 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. This summer we will have an opportunity to assess the long-term ramifications of the 2021 and 2022 summers and measure the response of glaciers to the weather of 2023 with detailed mass balance, crevasse depths and glacier surface elevation profiling.

Art Objectives: We will collaborate with several artists who will join us for a portion of the field season. They will be able to create their own work about the landscape and the science or may join us for fieldwork and make plans for future artwork. Potential artists include painters, a podcast creator, a photographer, and a printmaker. We hope to use this art to share our research with a broader audience and highlight the beauty and importance of these places.

Communication Objectives: We are seeking expedition sponsors this year with brands who have a climate change focus. These organizations can help spread our message; we have two so far. We are looking to support the production of podcasts as well.

Terminus change at two World Glacier Monitoring Service reference glaciers. Columbia and Eastson Glacier.

Field Team 2023:

Jill Pelto (she/her)is an artist and scientist from New England who grew up loving winter sports and trips to the mountains. She incorporates scientific research and data into paintings and prints to communicate environmental changes. Her multi-disciplinary work weaves visual narratives that reveal the reality of human impacts on this planet. She completed both her B.A. degrees in Studio Art and Earth and Climate Science, and her M.S. focused on studying the stability of the Antarctic Ice Sheet at the University of Maine, spending two field seasons at a remote camp in the southern Transantarctic Mountains. Jill will be joining the project for her 15th field season. She is excited about continuing to document the change in North Cascade glaciers that she has witnessed each of the last ten years — through science and art.

Painting by Jill Pelto that incorporates mass balance data from NCGCP from 1983-2022 along the top of the glacier.

Mauri Pelto (he/him) has directed the project since its founding in 1984, spending more than 800 nights camped out adjacent to these glaciers. He is the United States representative to the World Glacier Monitoring Service. For a decade he has been author of the AGU blog “From a Glacier’s Perspective,” and associate editor for three science journals. He is on the Science Advisory Board for NASA’s Earth Observatory. His primary position is Associate Provost at Nichols College, where he has been a professor since 1989. He either runs on trails or ski’s on trails alpine and cross country everyday.

Mauri Pelto looking at deglaciated envioronment below Easton Glacier

Mariama Dryak-Vallies (she/her) is the Director for the Polar Science Early Career Community Office (PSECCO) hosted by CIRES at University of Colorado Boulder. Mariama grew up on a farm in west-central Wisconsin before earning her B.A. in physical geography and archaeology at Durham University (UK)—where her passion for studying, researching, and teaching about glaciers, climate change, and the natural environment was born. She completed her M.S. in Earth and Climate Sciences at the University of Maine, studying Antarctic glaciology and ice-ocean interactions. During graduate school she was actively involved advocating for polar early career scientists as board member and co-chair of the US Association of Polar Early Career Scientists (USAPECS). Mariama is passionate about working towards building accessible Earth and polar sciences spaces for all.

2018 field team including Jill, Mauri, Mariama and Erin

Kaiyuan Wang (he/him) is a recent graduate from McGill University with a B.Sc in Honours Physical Geography, a minor in Geology. Originally from China, he developed an aspiration for Geoscience in the Great White North while living on the former bed of the Laurentide Ice Sheet. His passion for the cryosphere has led him to fieldwork on glaciers in the Kluane National Park in Yukon, Jasper National Park in Alberta, and a glaciological conference in Iceland. He will be doing his Ph.D. in Arctic Hydrology at the Northern Change Research Laboratory at Brown University. Kai is thrilled to be part of the 40-year-long effort of documenting glaciers as a living testimony to a warming world.

Shivaprakash Muruganandham (he/him) is currently a PhD candidate in Ocean Science and Engineering at the Georgia Institute of Technology, Atlanta, USA. He is back in school after a few years as a strategy consultant, during which time he specialized in satellites and space applications: earth observation and satellite communications in particular. Prior to this, he graduated with Master’s degrees in Space Technology and Cybernetic Systems/Control. Shiva is fascinated by ice, and his research focus on ice sheet/glacier modeling is motivated by his interests in the downstream impacts of cryosphere-climate interactions on coastal and mountain communities..

Field Partners 2023

Lizz Ultee (she/they) is an Assistant Professor of Earth & Climate Science at Middlebury College, Vermont. They earned a B.Sc. in mathematical physics at Queen’s University (Canada) and a Ph.D. in climate science at the University of Michigan, specializing in mathematical methods to understand and predict glacier change. Lizz finds ice endlessly inspiring. Beyond inspiring, though, glaciers are important for downstream communities — motivating Lizz’s present research focus on glacier contributions to sea-level rise and water resource availability.

Alia Khan’s research team including grad students Sally Vaux, Colby Rand, and Anne Wilce focus on environmental chemistry in the cryosphere, including black carbon and snow algae to document global change of glacier and snow melt in mountainous and polar regions.Western Washington University Cryosphere Studies and Aquatic Biochemistry Lab.

Claire Giordano is an environmental artist, writer, and educator creatively telling the stories of science, climate change, and the modern experience of nature. From creating rain-dappled sketches in an old growth forest to filming a watercolor class beside a glacier, careful observation of nature inspires her goal is to connect people and place through art. In 2021 she founded the Adventure Art Academy – a series of virtual watercolor classes filmed outside – to invite others into the joy of painting outside.

Field study by Claire Giordano, artist in residence with the NCGCP for her 4th year. She creates these incredible pages with notes, paintings, and sketches from her days out exploring the landscape.

Kathleen Shannon is a freelance journalist & radio producer telling science and environmental justice stories across the West. She is based in Missoula and earned a master’s degree in Environmental Science and Natural Resource Journalism from the University of Montana in 2023. Her work has appeared on NPR, in High Country News and elsewhere.

Julia Ditto is a science illustrator from Anchorage, Alaska who specializes in environmental and ecological graphics. Julia spends much of her time recreating in the backcountry, which inspires much of her work. She has always used art as a tool for observing and communicating her experiences, both inand out of the field. She is currently attending CSU Monterey Bay’s Graduate Science Illustration Program.

Who are we? NCGCP was founded in 1983 to identify and communicate the response of North Cascade glaciers to regional climate change. NCGCP is a field project including scientists and artists that has a broad interdisciplinary scope and examines more glaciers than any other program in North America. We do so cost effectively relying on no permanent camps or helicopter support. The field season includes no days off and each day is spent completing measurements on glaciers. The focus is on glacier mapping, mass balance measurement, terminus observations, glacier runoff monitoring and capturing the environment with art.

Why study glaciers in the North Cascades? Glaciers are one of the world’s best climate monitors and are a critical water resource to many populated glaciated regions. This is particularly true in the North Cascades where 700 glaciers yield 200 billion gallons of summer runoff and glaciers have lost 30 % of their area in the last century. This has reduced glacier runoff in late summer in the region as the reduction in glacier area has exceeded the increase in melt rate. During heat waves this role is even more profound with the glacier fed North Fork Nooksack River discharge rising ~24% due to greater melt, while unglaciated South Fork Nooksack River discharge declines by ~20%. The increased discharge limits the rise in river temperature during heat waves to 0.7 C in the North Fork, with the South Fork increasing by 2 C, increasing stress on the salmon in the South Fork (Pelto et al., 2022).

Retreat of Mount Baker glaciers documented by our program

The mass balance record we have compiled since 1984

Summer temperature records from NOAA WA Division 5

Winter Snowpack from North Cascade long term Snotel stations on April 1

Mount Baker Glacier’s Perspective on Climate Change 1984-2022-Disastrous!

On July 26, 2023April 19, 2024 By mspeltoIn North Cascade Glaciers4 Comments

Camp above Coleman Glacier on Heliotrope Ridge, (Jill Pelto painting)

Mount Baker is the most glaciated peak and highest mountain in the North Cascade Range at 3286 m. The Nooksack Indian Tribe refers to this strato volcano as Komo Kulshan, the great white (smoking) watcher. Mount Baker has 12 significant glaciers that covered 42 km² in 1984 and ranged in elevation from 1320 m to 3250 m. Kulshan watches over the Nooksack River Watershed, and its flanks are principal water sources for all three branches of this river and Baker River. In 1984 we began an annual monitoring program of glacier mass balance, terminus position and glacier area on these glaciers. Over the last 40 years we have visited these glaciers every summer observing their response to climate change.

In 1984/85 we visited 11 of the 12 glaciers mapping their terminus position. All but one had advanced between 1950 and 1975 emplacing an advance moraine. In the 1980’s as each glacier retreated from this moraine we used these prominent moraines as a benchmarks, as their ice cores have melted and erosion has occurred they have become less prominent. The distance from the typically well preserved, fresh moraines to the current glacier front has been measured in each case using a laser ranging device with an accuracy of +1m. In 2009 Mount Baker glacier had declined to 38.5 km² Pelto and Brown (2012). The Randolph Glacier Inventory reported a glacier area of 37 km² in 2015. In October 2022 an updated area was determined for Mount Baker glaciers at 33.5 km². This represents a decline of 20% in 38 years. Pelto and Brown (2012) identified a mean annual mass balance loss of -0.52 m/year from 1990-2010 on Mount Baker glaciers. From 2013-2021 the mass loss had more than doubled to -1.30 m/year. Below we review each glacier circling the mountain counter-clockwise

Measurement of glacier retreat from the advanced moraines ~1979 to 2022. We have measured terminus position of these glacier on 130 occassions from 1984-2022.

Easton Glacier from our survey camp in (2022) above and 2003 (below) illustrating 470 m retreat from 1990-2022.

Change at terminus from August 2022 to August 2023. Image from same location though different orientation area the size of a hockey rink lost all of its ice here.

Crevasse measurement of annual snowpack at 2500 m on Easton Glacier comparison of 2019-2022.

Easton Glacier flows down the south side of the mountain and feeds the Baker Lake Hydropower project. We have monitored the mass balance and terminus change of this glacier every year from 1990-2022. This is a World Glacier Monitoring Service reference glacier. In recent years thinning has exposed a few bedrock knobs near 2200 m on the glacier. The glacier has lost 21 m w.e. since 1990 driving a 470 m retreat during this interval. The pace of loss and retreat has been faster since 2013. The typical snowpack retained at the end of the summer has declined from 2.6 to 1.2 m w.e. at 2300 m.

Deming Glacier icefall indicating velocity locations and change in terminus from 1979.

The Deming Glacier drains the southwest side of the summit of Mount Baker a stratovolcano in the North Cascades of Washington, with a massive icefall feeding the lower valley terminus reach of the glacier. The icefall begins at 2200 meters and descends to 1600 meters. The glacier feeds the Middle Fork Nooksack River which provides water supply to Bellingham, WA. Deming Glacier flows from the summit and is the headwaters of the Middle Fork Nooksack River. We observed the terminus of this glacier every year from a survey point and conduct snow depth measurements at 2200 m on the glacier. he NASA Measures ITS_LIVE application uses feature tracking to determine glacier velocity. An examination of velocity change from the top of the icefall to the bottom on Deming Glacier from 2015-2022 indicates deceleration at the three points within or below the icefall, but no change at the top of the icefall. At the top of the icefall red X velocity has declined ~20%. In the middle of the icefall, green X, velocity has also declined ~20% since 2017. Near the base of the icefall, orange X, velocity has a chaotic signal lacking a clear trend. Below the icefall at the blue X, velocity has declined by ~20-30%. The resulting reduction in flux to the terminus will continue the rapid retreat. Pelto and Brown (2012) measured a 360 m retreat of Deming Glacier from 1979-2009, ~20 m/year. From 1979-2021 the glacier has retreated 725 m, with the rate of retreat from 2009-2021 of ~30 m/year.

Coleman Glacier and Roosevelt Glacier terminus at their maximum size in 1979, photo from Austin Post. Each has receded above the first prominent icefall step indicated by extensive crevassing.

Coleman and Roosevelt Glacier in 2014

In 1984 Coleman Glacier had just completed its advance begun in 1948. The Roosevelt Glacier on left almost merged with it and Coleman stretched across the Glacier Creek in the valley bottom leaving a prominent moraine that we surveyed retreat from. The Coleman Glacier has retreated 200 m upslope from Glacier Creek by 1997. Retreat has accelerated with 675 m of retreat from the 1979 moraine to 2022. In 2019 we surveyed the same line across the glacier at 1800 m that we had examined in 1988 and found the glacier had thinned by 38 m in this area.

Coleman Glacier Terminus in 2022.

Roosevelt Glacier retreating to top of bedrock step in 2019.

Roosevelt Glacier is adjacent to Coleman Glaier on the northwest side of Mount Baker. It has followed the same pattern as the Coleman Glacier with less total retreat since 1979 of 550 m. The glacier in 2022 has retreated above a large bedrock step and has a thin profile that will encourage ongoing rapid retreat.

Mazama Glacier in 2015

Looking up Mazama Glacier from near the saddle with Rainbow Glacier at 2000 m.

Mazama Glacier flows from the summit down the north side of Mount Baker. The glacier terminates at the head of Wells Creek at 1470 meters. This is a glacier we visit briefly each summer since 1984, but is not a focus of detailed observations. The glacier had a low slope relatively stagnant tongue in 1988 that has led to a rapid retreat of 825 m by 2022. The glacier has a high snow algae region near the Dorr Steamfield.

Sholes Glacier terminus in 2015 with stream gaging location, we calibrated this stream discharge station for the Nooksack Indian Tribe.

Sholes Glacier terminus in 2022 with 1984 terminus location indicated.

Sholes Glacier is on a ridge extending northeast from Mount Baker. We have surveyed mass balance on this glacier each year since 1990. In 2012 in a joint project with the Nooksack Indian Tribe we began summer long monitoring of streamflow below this glacier that has identified the response of glacier melt to heat waves (Pelto et al 2022). The glacier has lost 24.6 m w.e. thickness since 1990 and retreated 170 m, most of that retreat since 2010. Our studies of streamflow indicate how during heat waves glaciers in this basin increase discharge by ~20% and limit water temperature increases (Pelto et al 2022).

**Rainbow Glacier terminus in 2014 indicating the 2o14 and 1984 position. Taken by Tom Hammond from Rainbow Ridge.**

**Rainbow Glacier annual accumulaiton layer thickness in 2013.**

Rainbow Glacier is a World Glacier Monitoring Service reference glacier that we have measured the mass balance of each year since 1984.The glacier begins at 2200 m at a saddle with Mazama and Park Glacier and drains the northeast flank of Mount Baker into the headwaters of Rainbow Ceeek and then Baker Lake. The glacier has lost 17.7 m w.e thickness which has driven a retreat of 700 m. The glacier was advancing during our first two years of observations. At the 2000 m saddle with Mazama Glacier the accumulation zone has persisted. The average retained snowpack has declined from 2.7 m to 1.5 m.

Park Glacier Cliffs in 2003

Park Glacier drains the northeast side of Mount Baker’s summit area, meltwater flowing into Baker Lake. Each year we work on the adjacent Rainbow Glacier and during the 1980’s and 1990’s the Park Glacier Cliffs provided a daily sequence of avalanches, the noise echoing across the valleys. By 2010 this occurrence was rare, as the cliffs receded and diminished in height. This accompanied the retreat of the main valley tongue that most of these avalanches had fallen onto. By 2022 the glacier has receded 690 m from the advance moraine of the 1970’s

Boulder Glacier in 1993 from just below its 1970s advance moraine.

Boulder Glacier from our camp in 2003 illustrating retreat

Debris covered terminus of Boulder Glacier, due to subglacial debris exiting onto glacier surface

Boulder Glacier drains the east side of Mount Baker into Boulder Creek and then Baker Lake. The glacier was advancing rapidly in the 1950s. Our second visit in 1988 revealed a significant retreat underway. The terminus area of the glacier is debris covered due to subglacial debris flows from the crater exiting onto the glacier surface. This glacier has retreated 850 m retreat from its advance moraine of the 1970’s.

Talum Glacier in 1979 image from Austin Post

Talum Glacier has a wider bottom then top, as it is pinched between the Boulder and Squak Glacier on the east flank of Mount Baker. There are several terminus tongues, which tends to reduce the rate of retreat. Retreat from the advance moraines to 2022 has been 380 m.

Squak Glacier from survey camp in 1990

Squak Glacier from survey camp in 2009

Squak Glacier is adjacent to Easton Glacier on the southeast slope of Mount Baker. This glaciers retreat has been 420 m since 1984 when it was still in contact with its advance moraine. There are several bedrock areas emerging in what was the accumulation zone of the glacier, indicating a substantial expansion of the ablation zone. Thinning of the glacier from 1990-2009 is evident with expansion of ridge between Squak and Talum.

In 2023 we will again be on Mount Baker assessing the ongoing rapid response to climate warming generating glacier thinning and retreat.

Mount Baker Glaciers, Washington Snowpack Recession and Evolution May 2022-May 2023

On May 16, 2023April 19, 2024 By mspeltoIn North Cascade Glaciers1 Comment

Sholes Glacier snowcover extent change from 8-8-2022 to 10-17-2022. Snowcover declined from 98% of glacier to 10% of glacier during this period. Black dots are measurement sites, yellow dots the transient snowline, purple contour= 1.5 m, green contour= 2 m, brown contour= 2.5 m, and orange contour= 3 m snow depths on 8-8-2022.

The 2022 melt season for Moutn Baker glaciers was one for the record books, with a slow start and a prolonged intense melt lasting into Late October. Peak snowpack was not reached until May 20, 2022 at the Lyman Lake (1515 m) and Middle Fork Nooksack (1825 m) Snotel sites, with limited melt before June 1. These two sites have the highest correlation with our glacier mass balance observations (Pelto, 2018). Peak snowpack at Paradise, Mount Rainier (1565 m) was reached on May 26. The snowpack on June 1 at LL and MFN was 1.45 m Snow Water Equivalent (SWE) and 1.40 m SWE respectively. Snowpack at LL melted completely on July 14 and at MFN on July 11, with an average daily loss of 3.2 cm/day SWE. From June 1-Oct. 19 when the melt season ended, observed melt exceeded the previous highest years, we have observed during the 1984-2022 period. In 2023 peak snowpack was reached in mid-April at both LL and MFN, with rapid melt reducing snowpack during the first half of May.

Lyman Lake and Midde Fork Nooksack Snotel site snowpack depth in cm SWE observations beginning April 1 in 2022 and 2023. In 2022 May was a period of snowpack increase in 2022, while the first half of May 2023 has resulted in rapid snowpack depletion.

Heather Meadows snowpack depth (inches) at 1300 m, with 2022 rising above average during late April, while 2023 dips to average by the start of May.

On Sholes Glacier on August 6th-8th, 2022 we observed snow depths at 110 locations with an average snow depth of 2.25 m, 1.35 m SWE. We also checked two ablation stakes emplaced on June 1 indicating 3.55 m of snow melt, 2.1 m SWE. Sentinel images from Aug.8, Aug. 30, Sept. 9, Sept 27 and Oct. 17 reveal the recession of the snowline through the observation network allowing identification of snow ablation during these intervals. On Aug. 8, 98% of the glacier was snowcovered. On Aug 30, this had declined to 55%, with the snowline intersecting regions of the glacier that had 1.1 m SWE of snow cover on Aug. 8. By Sept. 9, the glacier was 40% snowcovered. On Sept. 27 the glacier was 25% snowcovered, with the snowline interseting sites that had 1.9 m SWE on Aug. 8. This is usually approximately the end of significant melt. However, in 2022 summer conditions continued through Oct. 19. The glacier was 10% snowcovered on Oct. 17, with the snowline intersecting sites that had 2.7 m SWE on Aug. 8.

The total observed snow melt for the June 1-Oct. 17 period was 4.8 m SWE on Sholes Glacier, eclipsing the previous June-end of melt season highs in 2015 of 4.0 m and in 2021 of 4.4 m. In both of those years the melt season did not extend into October, though May had significant melt. The Sholes Glacier did not suffer as much mass loss, because the initial snowpack was significantly greater in 2022. To have an equilibrium mass balance a glacier typically requires 55-65% of its area be snowcovered at the end of the melt season. A 10% snowcover indicates substantial mass losses.

On Rainbow Glacier on Mount Baker observations of snow depth on Aug 5-6, 2022 identified snow depths across the glacier. By Oct. 17th the areas of the glacier with 3.8 m or less of snowpack in early August had lost snowcover, indicating ablation of 2.4 m SWE of snowpack after early August. There was an area of exceptional snow algae at ~2100 m downwind of Dorr Steamfield on Rainbow Glacier, that Alia Khan’s Western Washington University research group examined. We led them through the Rainbow Icefall to this location.

On Easton Glacier, Mount Baker at 2500 m on Aug. 10th there was 5.25 m of snow remaining, compared to 2.75 m on September 27. At 2100 m there was 2.6 m of snowpack on August 10th with this snowpack melting completely between Sept,. 22 and Sept. 27. Indicating 1.6 m SWE of ablation during this period.

What 2022 illustrated is that a good winter season of accumulation, followed by a delayed melt season start, still cannot offset the persistent extended heat the region has experienced the last two summers. With the melt season off to a faster start in 2023 the outlook for Mount Baker glaciers is for another significant mass loss.

Snow depths on Rainbow Glacier on Aug 5-6, 2022.

Snow algae on Rainbow Glacier at 2100 m on Aug. 5th. Alia Khan’s WWU collecting samples.

Contrasting snow depth in crevasse in mid-August of 2020 and 2022 at 2500 m on Easton Glacier. Snow depths remaining on August 10, 2022 was ~5.25 m in 2022.

Snow depth at 2100 m on Aug 10th, 2022 on Easton Glacier

Loss of Hinman Glacier, North Cascade Range 1958-2022

On December 29, 2022April 20, 2024 By mspeltoIn climate change glacier retreat, North Cascade Glaciers11 Comments

Himan Glacier in 1958 USGS map and in 2022 Sentinel 2 False Color image. The three ice masses with an area greater than 0.01 km² are indicated.

Hinman Glacier had descended the northwest flank of Mount Hinman in the North Cascades, Washington and based on 1958 aerial photographs, Hinman Glacier the USGS had listed this as the largest glacier in the North Cascades south of Glacier Peak with an area of 1.3 km² (Post el al 1971). In 2022 the glacier is gone with the largest relict fragment of ice at 0.04 km². This is the story of this glaciers demise that as documented by the North Cascade Glacier Climate Project, that for 40 years has observed in the field the response of glaciers to climate change.

Hinman Glacier in 1988 with 4 distinct ice masses.

In the 1960’s the glacier extended from the ridge top of Mount Hinman at 2250 m to the bottom of the valley at 1675 m. In 1988, Hinman Glacier from the west was a group of four separated ice masses that we surveyed. The amount of blue exposed that year indicates the glacier lacked a consistent accumumulation zone. This is indicative of a glacier that cannot survive (Pelto, 2010). In 1992 we mapped the largest of these remaining ice masses at 0.12 km², this was another year with only pockets of blue ice left. In 1998 the glacier has a few areas of blue ice are seen, the glacier was 20% of its mapped size 0.25 km².

In 2005 we observed how thin the ice was including being able to see rock at the bottom of several crevasses (see below). In 2006, from a Google Earth image,at this point the glacier is no longer detectable under the snowcover that persisted that summer, note the map outline and the gorgeous new “Hinman” Lake The new lake is 1 km long. A 2009 view from the far end, north end of Lake Hinman up the valley and mountain side that was covered by the Hinman Glacier, now 90% gone. Each of the two larger ice masses from 1998 is now divided into at least two smaller portions. By 2022 the ice fragments have further diminished with the largest just 0.04 km2, less than 4% of its 1958 size. The tendency of this former glacier to be bare of snowcover by late August in many years, is what led to the rapid loss. This same story is playing out on Foss Glacier on the other side of the ridge, though not as quickly.

Hinman Glacier thin sections of ice fragmenting in 2005.

The loss of glacier area of this glacier and in the Skykomish River Basin has impacted summer runoff in the Skykomish River watershed. From 1958-2009 glacier area declined from 3.8 km² to 2.1 km², (Pelto, 2011), and in 2022 has further diminished to 1.7 km², a 55% reduction. We have monitored all four major glaciers in the basin Columbia, Foss, Hinman and Lynch Glacier, the primary glaciers in the basin, declined in area by 25%, 70%, 95% and 40% respectively since 1958. Despite 15% higher ablation rates during the 1985-2022 period, the 55% reduction in glacier area led to a 40-50% reduction in glacier runoff between 1958 and 2022. The impact on the Skykomish River is evident.

Glacier runoff on Hinman Glacier heading the Skykomish River. Streams like this used to drain across the glacier all summer long. Now they no longer exist to feed the Skykomish in late summer.

A key threshold of in-stream flow levels considered insufficient to maintain short term survival of fish stocks is below 10% of the mean annual flow (Tennant, 1976). For the Skykomish River 10% of mean annual flow is 14 m³s^-1. In the Skykomish River from 1958-2021 there have been 363 melt season days with discharge below 14 m³s^-1. Of these only three occurred before 1985, and 67% have occurred since 2003. The loss of 55% of the glacier runoff is a key reason for the onset of critical low flow days. Of more concern for aquatic life is the occurrence of extended periods of low flow (Tennant, 1976). From 1929-2021 in the Skykomish River basin there have been 12 years where streamflow dropped below 14 m³s^-1 for 10 consecutive days during the melt season, 1986, 1987, 1992, 1998, 2003, 2005, 2006, 2007, 2015, 2017, 2019, 2021 and 2022. Precipitation has not declined during this interval, hence earlier snowmelt, reduced glacier runoff and greater evapotranspiration must be causing the increase in late summer low flow periods.

In 2022 a cool start to summer allowed snowpack to persist in the basin into August. Runoff was strong from Columbia Glacier on Aug.1 as we forded the outlet stream, see below. By September glaciers represented the main area of melt. An extended warm period extending into October led to persistent low flow conditions, below 495 cfs (14 m³/sec), from Sept 9.-Oct. 20.

The former Himan Glacier from the new”Hinman” Lake that has formed since 1958 with glacier retreat, 3 small ice patches remain in this 2009 view.

Hinman Glacier basin in 2006 Google Earth view, with “Hinman Lake”.

Himan Basin in Open Elevation map and in 2022 Sentinel 2 False Color image.

Streamflow and temperature in the Skykomish River at the USGS site at Gold Bar. Period of low flow begins after flow drops below ~500 CFS.

(https://waterdata.usgs.gov/monitoring-location/12134500/)

Fording headwaters of North Fork Skykomish, which is the runoff from Columbia Glacier, on 8-1-2022.

Suiattle, White River, Whitechuck and Honeycomb Glaciers North Cascade Range Diminishing Rapidly

On October 28, 2022April 20, 2024 By mspeltoIn North Cascade Glaciers

USGS Map of the four glacier from 1984, with none of the seven lakes existing.

In 1988 we mapped four glaciers arrayed around the Kololo Peaks just south of Glacier Peak; Honeycomb and White River feeding into Wenatchee Lake watershed, while Whitechuck and Suiatlle fed into the Suiattle River watershed. They had a combined area of 9.2 km². The glaciers had not developed a series of proglacial terminus lakes at that time. We visited each glacier and completed observations in 1995 and 2002 illustrated the formation of six proglacial lakes, with one more developing after that, Lake #7. Further details and image for Whitechuck Glacier . In 2022 the glaciers have retreated away from each of these lakes that had not even begun to form in 1988. The combined area of the four glaciers in 2022 is 5.6 km², a 40% decrease in 34 years.

Whitechuck Glacier in 1988, with the North Branch and South Branch joined and terminating at Lake #5.

Whitechuck Glacier in 2002 with a detached glacier segment at Lake #5.

White River Glacier in 1988 with no lake yet formed at #3 or #4.

White River Glacier terminus with Lake #3 having formed, but still largely snowcovered in early August.

Honeycomb Glacier in 1995 with no lake #1 at the terminus yet.

Honeycomb Glacier in 2002 still in contact with Lake #1.

Kololo Peak glaciers in Sept. 9 2022 Sentinel image. H=Honeycomb, S=Suiattle, WC=Whitechuck, WR=White River, purple dots are the snowline and Point 1-7 proglacial lakes that formed after 1988 and are no longer in constact with glacier.

In 2022 we had the most extensive melting we have observed after September 1, with active significant melt extending to October 19. The result is striking in Sentinel images from Sept. 7 and Oct. 19 indicating the reduction in snowcovered area, the percentage of a glacier covered by snow is its accumulation area ratio (AAR). On September 9 the AAR of these glaciers was 45% diminishing to 10% by October 19. With negligible retained snowpack on Whitechuck and White River Glacier. Since 1988 Honeycomb Glacier has retreated 950 m, White River Glacier 475 m, Whitechuck Glacier 950 m and Suiattle Glacier 450 m.

Kololo Peak glaciers in Oct. 19, 2022 Sentinel image. H=Honeycomb, S=Suiattle, WC=Whitechuck, WR=White River, purple dots are the snowline and Point 1-7 proglacial lakes that formed after 1988 and are no longer in constact with glacier.

Lyman Glacier Lost Half its area from 1979-2022

On October 9, 2022April 20, 2024 By mspeltoIn climate change glacier retreat, North Cascade Glaciers

Map illustrating changes in Lyman Glacier 1890-2017- losing 87% of its area.

Lyman Glacier which feeds into Lyman Lake and then Railroad Creek in the Lake Chelan drainage of the North Cascade Range, Washington has retreated a total of 1330 m from the 1890 moraine. In 1929 year the terminus position was mapped by the Washington Water Power Company. The Washington Water Power Company emplaced a benchmark from which to measure retreat of the glacier which they monitored from 1929-1940. They found the glacier retreated 195 m from 1929-1940, and 530 m from the Little Ice Age Maximum to the 1940 position. William Long (Bill) visited the glacier with this party in 1940 and again in 1944 on leave from the 10th Mountain Division. In 1988 and 1990 Bill retured for the first times since 1944, with us, pointing out the benchmark. From 1986-2022 we have surveyd the terminus of this glacier in the field during 15 different summers. Lyman Glacier retreated 11 m/year 1940-1986, 11 m/year from 1986 to 2008, and 5.5 m/year retreat from 2008-2022. Retreat since our first field observations in 1986 has been 298 meters, 800 meters since 1940.

The area of the glacier in 2022 is 0.22 km², which is less than 13% of the 1890 area of 1.72 km². The glacier has been losing ~1% of its area per year since 1979. The glacier was noted to be in disequilibrium with climate and would melt away with current climate by Pelto (2010). From 1986-2008 the glacier reamined thick in the middle, over 40 m, as evidenced by a significant ice cliff into the lake. In 1986 this ice cliff maximum height was 15 m. The height increased to more than 20 m by 2003 and reached a maximum of 24 m high in 2008.. By 2011 the ice cliff had diminished to 15 m, and by 2022 to 2.5 m. The current glacier length is 360 m on the eastern portion and 400 m on the western portion. With retreat the slope in the glacier center has increased from 16 to 25 degrees from 1986-2022. The continued retreat at the 50 year retreat rate would eliminate the glacier in 35-50 years, but a simple extrapolation is typically not a good approach to determine when a glacier disappears. In 2008 we noted that the “glacier was still quite thick and should slow its retreat once the bedrock slope begins to increase, and the minor lake calving ceases.” Without a terminus ice cliff crevassing near the front has greatly diminished indicating that the terminus acceleration due to the ice cliff no longer exists. This retreat rate has slowed, while the rate of thinning due to mass balance loss has remained high ~1 m/year. The headwall also is the location of greatest avalanche accumulation, which also will slow retreat.

Additional details and images on Lyman Glacier.

1921 Mountaineers Expedition view of Lyman from the first upper Lyman Lakes shoreline (University of Washington Library), near the 1890 terminus position. Note the glacier is connected to the arm leading to Spider Gap top center.

Lyman Glacier in 1979 (USGS) no longer connected to spider gap section. A second upper Lyman lake has formed and the glacier terminates in this lake. The glacier is connected to upper Lyman Glacier extending top right.

Lyman Glacier in 1986. Debris pile from 1930’s avalanche just reaching front, calving front at terminus narrow and only 5-8 meters high, Mauri Pelto in foreground.

Lyman Glacier 2006 with very active crevassing behind 15-20 m high calving front. Glacier is disconnected from upper Lyman Glacier, top center.

Lyman Glacier in 2007 from far end of newest upper Lyman Lake near the 1940 terminus position.

2008 Terminus ice cliff that is 18-24 m high above and below.

Lyman Glacier 2011 most extensive snowpack in the 2000’s, ice cliff 10-15 m.

Lyman Glacier in 2022 from east margin reduced slope and size compared to similar viewpoint in 1988, Jill Pelto in foreground (Kevin Duffy-image)

Lyman Glacier 2022 with annotated measurements from the 2008 terminus locations and of terminus condition. Kevin Duffy on the terminus rock. (Jill Pelto-Image)

North Cascade Glacier 2022 Initial Observations-39th Field Season

On September 7, 2022April 20, 2024 By mspeltoIn North Cascade Glaciers2 Comments

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 39^th 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.

NORTH CASCADE GLACIER CLIMATE PROJECT 2022-39th Annual Field Program

On July 29, 2022April 20, 2024 By mspeltoIn North Cascade Glaciers

Mount Baker camp for Rainbow and Sholes Glacier (Illustration by Megan Pelto)

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

2022 Field Season: For the 39^th consecutive summer we are heading into the field to measure and communicate the impact of climate change on North Cascade glaciers. We will complete 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.

Who we are? 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. The goal of this is to best document and share our research with a broad audience. We aim to bring stories of these places and their changes to as many people as we can, making our research feel personal to more than just our team. The North Cascades glaciers are important for the ecosystem, as a water resource to Washington, and as a place of recreation for so many. By monitoring them every year, we continue to provide critical data on glacier response to climate change and informed stories of their health that reveal the impacts of our warming world.

2021 Field Team for Rainbow Glacier

Why study glaciers in the North Cascades? Glaciers are one of the world’s best climate monitors and are a critical water resource to many populated glaciated regions. This is particularly true in the North Cascades where 700 glaciers yield 200 billion gallons of summer runoff and glaciers have lost 30 % of their area in the last century. This has reduced glacier runoff in late summer in the region as the reduction in glacier area has exceeded the increase in melt rate. During heat waves this role is even more profound with the glacier fed North Fork Nooksack River discharge rising ~24% due to greater melt, while adjacent unglaciated South Fork Nooksack River discharge declines by ~20% (Pelto et al., 2022). The increased discharge limits the rise in river temperature during heat waves to 0.7 C in the North Fork, with the South Fork increasing by 2 C. This increases stress on the salmon in the South Fork (Pelto et al., 2022).

Terminus Change at Columbia and Easton Glacier.

This field season follows the 2021 season that featured a historic heat wave at the end of June and a period of extended warm weather that lasted until Mid-August. The heat led to a greater exposure of bare ice on glaciers earlier in the summer, particularly at higher elevations. For ice surfaces with a higher albedo and greater density the observed melt rates are 7-9 cm per day water equivalent during warm weather events vs 4-6 for snow surfaces. This led to substantial mass losses on North Cascade glaciers, -2 m.

This summer we will have an opportunity to assess the long-term ramifications of the 2021 summer and measure the response of glaciers to the weather of 2022. This winter snowpack remained below average until a late season surge from April into May. The month of May and June had below normal temperatures leading to an above average snowpack. A hot July has melted into this snowpack and we will observe how much remains on the glaciers.

Field Team 2021:

Jill Pelto is an artist and scientist from New England who grew up loving winter sports and trips to the mountains. She incorporates scientific research and data into paintings and prints to communicate environmental changes. Her multi-disciplinary work weaves visual narratives that reveal the reality of human impacts on this planet. She completed both her B.A. degrees in Studio Art and Earth and Climate Science and her M.S. focused on studying the stability of the Antarctic Ice Sheet at the University of Maine, spending two field seasons at a remote camp in the southern Transantarctic Mountains. Jill will be joining the project for her 14th field season. She is excited about continuing to document the change in North Cascade glaciers that she has witnessed each of the last ten years — through science and art.

Mauri Pelto has directed the project since its founding in 1984, spending more than 700 nights camped out adjacent to these glaciers. He is the United States representative to the World Glacier Monitoring Service, author of the AGU blog “From a Glacier’s Perspective”, and associate editor for three science journals. He is on the Science Advisory Board for NASA’s Earth Observatory. His primary position is Associate Provost at Nichols College, where he has been a professor since 1989.

Echo Allen is a rising Junior at UC Berkeley studying Architecture and Sustainable Design. Her studies deal with urban ecology and environmental justice in relationship to physical design. Echo finds inspiration for her studies in the backcountry as a NOLS backpacking student, avid rock climber, and kayak guide. Echo is currently working with the City of Richmond and SHAC (Sustainable Housing at Cal) to design and construct an affordable and scalable model of a solar-powered off-grid capable tiny house that will be used as affordable housing in Richmond CA. She hopes to help people understand the impact of climate change and implement possible mitigation strategies through her work in outdoor education and architecture.

Ellie Hall (she/her) is a recent graduate from the University of Colorado – Boulder with a BA in Environmental Studies, a minor in Geology, and a certificate in Arctic Studies. She is interested in researching and documenting the nuanced impacts of climate change on cold regions, and especially learning more about the relationship between decreasing snowpacks and increasing wildfires. She has spent the past two summers researching these areas, interning with INSTAAR’s Arctic Rivers Project and NASA’s ABoVE Campaign. She is excited to get into the field this summer to see the theoretical knowledge she’s learned be put into practice to collect valuable data. Ella’s other interests include backcountry skiing, mountain and gravel biking, rock climbing, and water sports.

Jenna Travers (she/they) is about to start her final year as a marine biology major at the University of Oregon. Her research focuses on the impacts of glacier retreat on salmon, how communities are affected by glacier loss and salmon declines, and how climate issues are communicated to the public. They are currently working as a writer with GlacierHub and a salmon identification contractor with the Wild Salmon Center, and they have also worked as a legislative intern for the Oregon State Legislature, a Water Justice intern with a local nonprofit. In her free time, Jenna enjoys hiking, skiing, rock climbing, and playing games with her roommates.

Field Partners 2022

Alia Khan’s research team including grad students Sally Vaux and Shannon Healy focus on environmental chemistry in the cryosphere, including black carbon and snow algae to document global change of glacier and snow melt in mountainous and polar regions. Western Washington University Cryosphere Studies and Aquatic Biochemistry Lab.

Jaclyn Baer is an artist and photographer in the PNW. She is new to the climate change artist role, but excited to learn and share. She loves painting with gouache in her studio and watercolor out in the field. Besides painting, she spends her free time hiking and backpacking with her husband Ryan.

Nooksack Indian Tribe, for the 11^th consecutive year, we will be conducting field work aimed at providing field validation and streamflow calibration data below Sholes Glacier for the ongoing work of the tribe.

Crevasse Stratigraphy on Easton Glacier

2022 Field Schedule

Jul 31:  Hike in Columbia Glacier
Aug. 1:  Columbia Glacier
Aug. 2:  Columbia Glacier
Aug. 3:  Hike Out Columbia, Hike in Ptarmigan Ridge
Aug. 4:  Sholes Glacier
Aug. 5:  Rainbow Glaciern
Aug. 6:  Rainbow Glacier
Aug.7:   Hike out, Hike in Lower Curtis Glacier
Aug. 8:  Lower Curtis Glacier
Aug. 9:  Hike out, Hike in Easton Glacier
Aug. 10: Easton Glacier
Aug. 11: Easton Glacier
Aug. 12: Hike out Easton/Hike in Daniel
Aug. 13: Ice Worm Glacier Survey
Aug. 14: Daniel and Lynch Glacier Survey
Aug. 15: Ice Worm ablation, Hike out
Aug. 16: Field season concludes

Deming Glacier Icefall Deceleration 2017-2022 Driven by Mass Balance Loss

On July 26, 2022April 20, 2024 By mspeltoIn North Cascade Glaciers

Deming Glacier velocity from NASA MEaSUREs ITS_Live at four locations from below icefall at blue X to above icefall at red X. There is not a significant change in velocity above the icefall (red X), but significant deceleration in the icefall and below the icefall.

The Deming Glacier drains the southwest side of the summit of Mount Baker a stratovolcano in the North Cascades of Washington, with a massive icefall feeding the lower valley terminus reach of the glacier. The icefall begins at 2200 meters and descends to 1600 meters. The glacier feeds the Middle Fork Nooksack River which provides water supply to Bellingham, WA. I first observed the Deming Icefall from the terminus area of the glacier in 1987. This visit demonstrated that it is not safe to hike to the terminus of this glacier. In 1990 we began annual observation of Deming Glacier. Each summer we monitor the adjacent Easton Glacier in detail including mass balance, while also taking several specific observations of Deming Glacier including terminus position, and accumulation between 2400-2700 m. This combined with mass balance assessment on Easton Glacier provides an annual assessment of the meltwater provided by the glacier to the Nooksack River system. During heatwaves the tributaries of the Nooksack fed by glaciers have had the impacts mitigated, while those without glaciers have seen significant temperature increase and discharge decrease (Pelto et al 2022).

Pelto and Brown (2012) identified a mean annual mass balance loss of -0.52 m/year from 1990-2010 on Mount Baker glaciers. From 2013-2021 the mass loss had more than doubled to -1.30 m/year. The declining mass balance is less pronounced above the icefall. The icefall transitions the glacier from the accumulation zone to the ablation (melt) zone at the bottom of the icefall. Above the icefall at 2400-2700 meters the average snow depth left at the end of the summer based on several thousand crevasse stratigraphy measurements from 1990-2013 had been 2.75 meters, from 2014-2021 the average depth has been 2.4 m.

The result of the declining mass balance of the entire glacier and the upper glacier will be glacier deceleration. The NASA Measures ITS_LIVE application uses feature tracking to determine glacier velocity. An examination of velocity change from the top of the icefall to the bottom on Deming Glacier from 2015-2022 indicates deceleration at the three points within or below the icefall, but no change at the top of the icefall. At the top of the icefall red X velocity has declined ~20%. In the middle of the icefall, green X, velocity has also declined ~20% since 2017. Near the base of the icefall, orange X, velocity has a chaotic signal lacking a clear trend. Below the icefall at the blue X, velocity has declined by ~20-30%. The resulting reduction in flux to the terminus will continue the rapid retreat. Pelto and Brown (2012) measured a 360 m retreat of Deming Glacier from 1979-2009, ~20 m/year. From 1979-2021 the glacier has retreated 725 m, with the rate of retreat from 2009-2021 of ~30 m/year.

View of the Deming Glacier from terminus to top of icefall in 2019. Jill Pelto at left, Abby Hudak and Mauri Pelto at right. X’s mark the velocity locations, Point A ties this to the upper glacier view, red arrow is the 1987 terminus location.

The icefall sweeps around a bedrock with an east and a west arm splitting above and rejoining below the knob.

The Deming Glacier from the top of the icefall to the summit of Mount Baker in 2020.

In mid-August 2022 snowpack was particularly low right to the top of Deming Glacier. Comparison with 2020 which was an average year for the last decade, but still a significant mass balance loss.

Terminus of Deming Glacier in 2004 and 2019 illustrating the ongoing retreat of the terminus, 725 m from 1979-2021.

Jill Pelto measuring Crevasse depth and snowpack thickness in Crevasse at 2500 m on Deming Glacier.

From a Glaciers Perspective

Category: North Cascade Glaciers

Cascade Pass Area Loses Two Glaciers

From Mount Hood to Mount Robson Extremely Limited 2023 Snowcover Retained

Written by Ben Pelto, Jill Pelto and Mauri Pelto

Collapse of the Glacier Complex on Mount Daniel-Hinman, Washington

40th Field Season of North Cascade Glacier Climate Project Underway

Field Team 2023:

Field Partners 2023

Mount Baker Glacier’s Perspective on Climate Change 1984-2022-Disastrous!

Mount Baker Glaciers, Washington Snowpack Recession and Evolution May 2022-May 2023

Loss of Hinman Glacier, North Cascade Range 1958-2022

Suiattle, White River, Whitechuck and Honeycomb Glaciers North Cascade Range Diminishing Rapidly

Lyman Glacier Lost Half its area from 1979-2022

Map illustrating changes in Lyman Glacier 1890-2017- losing 87% of its area.

1921 Mountaineers Expedition view of Lyman from the first upper Lyman Lakes shoreline (University of Washington Library), near the 1890 terminus position. Note the glacier is connected to the arm leading to Spider Gap top center.

Lyman Glacier in 1979 (USGS) no longer connected to spider gap section. A second upper Lyman lake has formed and the glacier terminates in this lake. The glacier is connected to upper Lyman Glacier extending top right.

Lyman Glacier in 1986. Debris pile from 1930’s avalanche just reaching front, calving front at terminus narrow and only 5-8 meters high, Mauri Pelto in foreground.

Lyman Glacier 2006 with very active crevassing behind 15-20 m high calving front. Glacier is disconnected from upper Lyman Glacier, top center.

Lyman Glacier in 2007 from far end of newest upper Lyman Lake near the 1940 terminus position.

2008 Terminus ice cliff that is 18-24 m high above and below.

Lyman Glacier 2011 most extensive snowpack in the 2000’s, ice cliff 10-15 m.

Lyman Glacier in 2022 from east margin reduced slope and size compared to similar viewpoint in 1988, Jill Pelto in foreground (Kevin Duffy-image)

Lyman Glacier 2022 with annotated measurements from the 2008 terminus locations and of terminus condition. Kevin Duffy on the terminus rock. (Jill Pelto-Image)

North Cascade Glacier 2022 Initial Observations-39th Field Season

NORTH CASCADE GLACIER CLIMATE PROJECT 2022-39th Annual Field Program

Deming Glacier Icefall Deceleration 2017-2022 Driven by Mass Balance Loss

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Written by Ben Pelto, Jill Pelto and Mauri Pelto

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Field Team 2023:

Field Partners 2023

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Map illustrating changes in Lyman Glacier 1890-2017- losing 87% of its area.

1921 Mountaineers Expedition view of Lyman from the first upper Lyman Lakes shoreline (University of Washington Library), near the 1890 terminus position. Note the glacier is connected to the arm leading to Spider Gap top center.

Lyman Glacier in 1979 (USGS) no longer connected to spider gap section. A second upper Lyman lake has formed and the glacier terminates in this lake. The glacier is connected to upper Lyman Glacier extending top right.

Lyman Glacier in 1986. Debris pile from 1930’s avalanche just reaching front, calving front at terminus narrow and only 5-8 meters high, Mauri Pelto in foreground.

Lyman Glacier 2006 with very active crevassing behind 15-20 m high calving front. Glacier is disconnected from upper Lyman Glacier, top center.

Lyman Glacier in 2007 from far end of newest upper Lyman Lake near the 1940 terminus position.

2008 Terminus ice cliff that is 18-24 m high above and below.

Lyman Glacier 2011 most extensive snowpack in the 2000’s, ice cliff 10-15 m.

Lyman Glacier in 2022 from east margin reduced slope and size compared to similar viewpoint in 1988, Jill Pelto in foreground (Kevin Duffy-image)

Lyman Glacier 2022 with annotated measurements from the 2008 terminus locations and of terminus condition. Kevin Duffy on the terminus rock. (Jill Pelto-Image)

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