Team Perspectives from 2026 North Cascade Glacier Climate Projects Field Season

On August 22, 2026August 22, 2026 By mspeltoIn climate change glacier retreat, glacier climate change, Glacier Observations, North Cascade GlaciersLeave a comment

Jill Pelto: Field painting of new large bedrock exposures in the big icefall on Easton Glacier, Mt. Baker. The 2026 field season of the NCGCP brought dramatic changes. While we expected most of these, it doesn’t make them any easier to physically navigate or emotionally experience. Even at 9,000 ft, the glaciers of Mt. Baker are thinning, with new bedrock emerging. Above about 7,000 ft, the snowpack was decent, which will slightly help to mitigate the losses from lack of snowpack at lower elevations. The atmospheric river carved a story across our field sites. From this big shift in snowpack up high, to washed out roads, and altered riverbeds. It was a year of fascinating, sad, and occasionally hopeful shifts.

Abby Connor: Looking down at the terminus of the Lower Curtis Glacier on Mt. Shuksan, noticeably thinner than when I last visited. I grew up in Bothell, in a family that spends its weekends outdoors, assuming that massive and seemingly unchanging glaciers are a fact of life. But as we approached our first field site on the Lower Curtis Glacier on Mt. Shuksan, I struggled to reconcile the view of the noticeably less massive terminus of the glacier with my memory from my last visit eight years ago. When we reached our break spot and looked far down at the glacier, Mauri described the wall that would have towered 100 feet over where we sat, before the glacier had lost its impressive thickness. Throughout the 2026 field season, I was continually awed with the scale of the glaciers we still have in the North Cascades while surrounded by reminders of how quickly they’re disappearing, fast enough that we are on track to lose almost all of our glaciers in the state within my lifetime. In Western Washington, a place defined by the mountains and Sound, glaciers are the link between the two. They are no longer an unchanging fact of life.

Ava Reynolds: Pink monkey flower and fireweed bloom in the rocky moraine of the Columbia Glacier – one of the glaciers in the 2026 field season that looked the most impacted by warm temperatures and a reduced snowpack, with avalanche bands that feed the glacier now shutoff, rockfall evident across the entire glacier, and a growing lake of floating ice at the terminus.This field season was visually striking, highlighting the impact of our warming climate on the glaciers and surrounding ecosystem. Flowers were blooming weeks ahead of schedule, sections of new bedrock were exposed, wildfires dotted the horizon at every field site, and residual evidence from the December 2025 storm system was prevalent in downed trees and washed out riverbeds.

Shaina Dotson: Amidst the icefall of Easton Glacier. Joining the NCGCP this field season was equal parts breathtaking and sobering. Each glacier was stunning and wholly its own — ancient and irreplaceable — yet we were immersed in the evidence of a warming planet. Wildfire plumes lined the horizon, ice thinned and retreated where it once held firm, and every day I found myself torn between the beauty of this world and its unraveling.

Danielle Schlunegger-Warner: Red Lens over Rainbow Glacier with Ice Alge sampled from Rainbow Glacier in the microscope. As an artist invited out to attend the 43rd field season with NCCGP, I spent my time in immersed with looking and observing. My attention drew not just to the fantastical forms of the ice on the glaciers, but the way they change the landscape around them. I saw ice algae and tiny black worms dotting the ice and snow, listened to the life bubbling up in the streams at their edges.The focus shifted between the expansive ancient glaciers, microorganisms, and the yearly changes diligently measured by the NCCGP with somber results. This experience illuminated for me not just that these glaciers the heartbeat of the North Cascades, but that their impact ripples out into our own lives in ways that are worth paying more attention to.—I had a tough time picking an image! If possible I’d love to share either the large lens picture or the Alge and red lens together. Send along what makes the most sense!

Rikki Held: Rainbow Glacier cave with Mauri for scale. The 43rd field season of the NCGCP was filled with both devastating and beautiful moments. We traversed landscapes with fresh glacier-fed streams, rugged mountains, wildflowers, mountain goats, and glaciers with unique formations and characteristics, while also witnessing heartbreaking sites including the large cave hollowing out Rainbow Glacier’s terminus on Mt. Baker and wildfire smoke plumes throughout the field season. Mauri and Jill shared their multi-year observations noting vegetation changes, newly exposed bedrock, and how far the glaciers have receded since they first visited them – e.g., Easton Glacier has retreated around 750m since 1990. This project highlights the importance of long-term data collection, science communication, and personal narratives as we all work to reduce the impacts of anthropogenic climate change and protect the environmental systems we depend on.

Mauri Pelto: Rainbow Glacier cave at the terminus with Abby and Rikki in foreground, viewed from an area where a previous cave had collapsed. Large ice caves are features of retreating glaciers where warm air circulates expanding the cave until it collapses. We observed several of these at the terminus of glaciers on Mount Baker this summer. The largest was at the terminus of Rainbow Glacier. The cave is large enough to hold a cape style house. It will collapse by the end of summer driving further retreat. The size of this cave and the roar of the water was quite intimidating.

Petermann Glacier, NW Greenland Releases Massive Iceberg in August 2026.

On August 17, 2026August 20, 2026 By mspeltoIn climate change glacier retreat, Greenland glacier retreat1 Comment

Petermann Glacier in Landsat images from July 21st and Aug. 13 2026. Indicating the rift that leads to iceberg calving of berg A-yellow arrows. Additional significant rifting inidicated by red arrows. Berg B is not a stable configuration.

The Petermann Glacier in northwest Greenland is significantly different than the fast flowing large outlet glaciers, such as the Jakobshavn and Helheim Glacier we here so much about. Petermann Glacier is much thinner at the calving front and moves much slower. The volume flux from this glacier is much less than Jakobshavn which loses 40 km³ per year, versus 1 km³ at the calving front of Peteramann and 12 km³ at the grounding line. A detailed review of some of the differences is explored in an article I wrote for Realclimate in 2008. In 2008 Petermann Glacier lost a substantial area, 29 km² due to calving. Additional large calving events in 2010, when a 250 km² berg broke off and in 2012 a 32 km² berg broke off (NASA, 2023).

This summer the rifts that have been evident for some time cutting across the glacier led to a calving event on Aug. 4th, reported by Univesity of Ottawa researcher Adam Garbo. Because of the flat nature of this feature it can be referred to as an ice island as well. Imagery from July 21 indicates no calving. By August 6th berg A, with an area of 75km² . The glacier thickness at the calving front is less than 150 m, which allows this berg to cross the sill that is 350-450 m deep (Tinto et al 2015), and move out of the fjord. The berg has moved 28 km from Aug. 4 to Aug. 13, a velocity of ~3 km per day. Becuase the ratio of berg length and width to thickness, this is not an iceberg that will turnover. Exiting the fjord the iceberg has turned southwest.

Existing rifting indicates that additional iceberg B will break off in the near future, behind this additional rifting indicates a weakness cutting across almost the entire glacier for additional calving that will occur in the next several years, though likely not as a single large ice berg. This is the largest observed calved ice berg in the Northern Hemisphere in 2026.

Petermann Glacier in Landsat images from Aug. 6th and Aug. 13 2026. The iceberg has separated by just a 5 kilometers by Aug. 6th, and 28 km by Aug. 13th. Additional significant rifting inidicated by red arrows. Berg B is not a stable configuration.

Global Alpine Glacier 2025 State of Climate Report

On August 15, 2026 By mspeltoIn climate change glacier retreat, glacier climate change, Glacier ObservationsLeave a comment

**Figure 1. Global mean annual balance (bars) and cumulative balance (line) from the WGMS data set.**

Each year since 2008 I have been responsible for summarizing the global alpine glacier status for each specific year in the Bulletin of the American Meteorological Society State of the Climate report. The 2025 report came out in early August. Below is the report with several added figures.

The 2025 World Glacier Monitoring Service (WGMS) dataset of annual glaciological mass balance observations includes 162 glaciers from six continents and 26 nations, 158 with a negative balance and four with a positive balance. In 2025, the mean annual mass balance of the 59 reporting global reference glaciers was –1.34 m w.e., and -1.34 m w.e. for all 162 reporting glaciers. The 2025 regionalized global average annual balance of –1.09 m w.e., is the fourth consecutive year with mass balance loss exceeding 1.0 m w.e., 2023 had the most negative -1.23 m w.e and 2024 was at 1.04 m w.e. Since 1976, mountain glaciers and ice caps have lost 9179+621 Gt of water, contributing 25.3+1.7 mm to the global mean sea level rise, with 41% of this loss occurring in the last decade (Dussaillant et al. 2025).

The mean annual balance of global reference glaciers was -1.34 m w.e., a similar result to 2023 and 2024 with a mean annual balance for global reference glaciers of -1.60 m w.e. and -1.37 m w.e., respectively. This makes 2025 the 38^th consecutive year with a global alpine mass balance loss, the 16^th consecutive year with a regionalized global mass balance below –0.5 m w.e. The significant acceleration of mass balance loss is evident in glaciological observations, geodetic observations, altimetry observations and gravimetric observations (The GlaMBIE Team, 2025). The acceleration of mass balance loss indicates glaciers are not approaching equilibrium and increasingly are disappearing. The Global Land Ice Measurement from Space inventory of global glaciers has now added an extinct glacier layer to record glaciers that have disappeared, that is populated by 181 glaciers that had existed in a previous inventory (Raup et al. 2025). In conjunction with 2025 being the UN International Year for Glaciers’ Preservation the Global Glacier Casualty List has been created to chronicle the story of specific glaciers being lost from each glaciated region (Boyer and Howe, 2025).

**Hofsjokull eystri, Iceland was snow free by mid-August, leading to extensive ice cap thinning.**

In the European Alps all 54 glaciers observed had negative balances, with 45 of the glaciers losing over 1 .0 m w.e. In Iceland (6) and Svalbard (9) all 15 glaciers observed lost over 1.0 m w.e. In Norway 8 of 10 glaciers had a negative balance, with two glaciers having a positive balance. In Sweden 3 of 4 glaciers had a negative balance.

**High snow line on Durung Drung Glacier, India near end of summer monsoon season.**

In Asia all 23 glaciers across 7 nations had negative balances averaging 0.97 m w.e. In New Zealand the glaciers observed had a negative mass balance.

**Agua Negra Glacier, Argentina with minimal snow cover at end of summer melt season.**

In the Andes Mountains of South America nine of ten, reporting from four nations, had negative balances, with an average balance of -0.92 m w.e.

All 14 glaciers in Western North America, outside of Alaska, had mass balance below -1.0 m w.e. with an average of -2.24 m w.e. Peyto Glacier, Canada exemplifies the limited retained snow cover on alpine glaciers in Western North America in 2025, a glacier should be 50-60% snow covered at the end of summer to be in equilibrium (Fig X2). It is evident Peyto Glacier is representative of adjacent glaciers that also have limited retained snow cover. In Alaska 3 of 4 glaciers had negative balances. The five glaciers in Arctic Canada all had small negative balances averaging -0.16 m w.e.

**Snow cover was minimal in the Yoho-Peyto Glacier regions, Canada at the end of the melt season.**

Alpine annual mass balance glaciological observations are reported to the WGMS by National representatives with a December 1 annual submission deadline. WGMS reference glaciers (60) have at least thirty continuous years of mass balance observation. Benchmark glaciers (23) have at least a ten-year mass balance record and are in regions that lack sufficient reference glaciers. The combination of benchmark and reference glaciers are used to generate regional averages (WGMS, 2023). Global values are calculated using a single averaged value for each of 19 mountain regions, limiting bias from observed regions (WGMS, 2023). Expansion of this data set leads to reanalysis and updated values.

References

Boyer, D. and Howe, C. 2025. Communication efforts to educate the public about vanishing glaciers, 1958–2025. Annals of Glaciology, 67: e2. doi:10.1017/aog.2025.10033

Dussaillant, I., Hugonnet, R., Huss, M., Berthier, E., Bannwart, J., Paul, F., and Zemp, M. 2025: Annual mass change of the world’s glaciers from 1976 to 2024 by temporal downscaling of satellite data with in-situ observations. Earth System Science Data 17(5): 1977-2006, https://essd.copernicus.org/articles/17/1977/2025/.

Raup, B., Andreassen, L., Boyer, D., Howe, C., Pelto, M., and Rabatel, A. 2025: Tracking extinct glaciers in GLIMS. Annals of Glaciology, 66, e35, 1–6. https://doi.org/10.1017/aog.2025.10027

The GlaMBIE Team, 2025: Community estimate of global glacier mass changes from 2000 to 2023. Nature. https://doi.org/10.1038/s41586-024-08545-z.

WGMS 2023: Global Glacier Change Bulletin No. 5 (2020–2021). Zemp, M., Gärtner-Roer, I., Nussbaumer, S.U., Welty, E.Z., Dussaillant, I., and Bannwart, J. (eds.), ISC(WDS)/IUGG(IACS)/UNEP/UNESCO/WMO, World Glacier Monitoring Service, Zurich, Switzerland, 134 pp., publication based on database version: doi:10.5904/wgms-fog-2023-09. [NG5] [MP6]

Datasets used and their URLs

Dussaillant, I., Hugonnet, R., Huss, M., Berthier, E., Bannwart, J., Paul, F., and Zemp, M. (2025): Annual mass-change estimates for the world’s glaciers. Individual glacier time series and gridded data products. Digital media. https://doi.org/10.5904/wgms-amce-2025-02b [NG7] [MP8]

Miles Glacier, Alaska Retreat-Van Cleve Lake Outburst 2026

On July 11, 2026 By mspeltoIn alaska glacier retreat, climate change glacier retreat, glacier climate change2 Comments

**Miles Glacier and Van Cleve glacier lake (VC) near its maximum size on June 19th and after drainage on July 9th in Sentinel images. Glacier margin black dots.**

Miles Glacier terminates in an embayment on the east side of the Copper River, Alaska. A secondary terminus on the north side of the main glacier has long impounded a glacial lake that periodically drains. As miles has retreated over the last 40 years the maximum size of the glacial dammed lake has diminished, prior to its drainage. In 1987 the glacier extended onto an outwash plain directly adjacent to the Copper River, the lake reached a maximum size of 12 km² . From 2016 to 2019 the lake drained each summer reaching a maximum average size of 5.5 km² (Rick et al 2023). This was noted as a shrinking ice dammed lake by Field et al (2021).

**Miles Glacier and Van Cleve glacial lake filling in June 2026 in Landsat images.** **Glacier margin black dots.**

By 2021 the glacier had retreated 3.5 km since 1987. From 2021-2026 the lake reaches a maximum size of 3.5 to 4.0 km² before draining. On June 2, 2026 the lake still has some winter lake ice and is filling. By June 10th the lake had reached 3 km² and by June 19th it had reached 4 km². The lake had began draining before June 25th. By July 9th it was fully drained. The Miles Glacier terminus has retreated 4.5 km since 1987. This ongoing retreat will continue to diminish the size of the lake. Ths lake does not have the complex drainage system or changing drainage location that Berg Lake has with retreat of Stellar Glacier..

**Miles Glacier and Van Cleve glacial lake in 1987 Landsat image. Black dots indicate glacier margin.**

**Miles Glacier and Van Cleve glacial lake in 2021 Landsat image. Black dots indicate glacier margin and yellow arrow indicates 1987 margin.**

Hovgard Kystland Glacier Rapid Retreat, West Greenland

On July 6, 2026July 6, 2026 By mspeltoIn climate change glacier retreat, glacier climate change, Glacier Observations, Greenland glacier retreatLeave a comment

**Hovgard Kystland Glacier in Sentinel image from July 4, 2026 with margin indicated by black dots. The 2020 margin seen below is indicated by green dots.**

Hovgard Kystland Glacier is an outlet glacier in West Greenland between Alison and Hayes Glacier. Alison Glacier had the highest retreat rate from 1976-2021 losing 14.3 km in length and 59.4 km² in terminus area (Black and Joughin, 2026). Hayes Glacier lost 2.7 km in length and 10.8 km2 in area (Black and Joughin, 2026).. They indicate that Hovgard Kystland Glacier retreated 5.4 km and lost 21.3 km² during this interval.

Here we examine the acceleration of retreat from 2020 to 2026. In 2020 the central tongue of the glacier extended west beyond the main front. This central tongue collapsed by July 2024 leaving a generally north/south calving front, the glacier had lost 5.7 km² of terminus area. From July 2024 to July 2026 an embayment formed generating a concave calving front. The glacier terminus lost another 4.8 km of area. Retreat of the calving front was 2.5 km during the 2021-2026 period. The glacier has lost an area that is 50% of the area lost from 1976-2021, in the last five years. The embayment is poised to further expand, though this summer an extensive packed melange is currently in place which typically limits calving (Meng et al. 2025).

**Hovgard Kystland Glacier in Sentinel image from July 27, 2020. The 2020 margin seen below is indicated by green dots and the 2026 margin with black dots.**

**Hovgard Kystland Glacier in July 4, 2024 Sentinel image. The calving front indicated by red dots for 2024 and black dots for 2026.**

Alpine Glaciers-State of Climate 2024

On July 2, 2026July 2, 2026 By mspeltoIn climate change glacier retreat, glacier climate changeLeave a comment

**Global alpine mass balance in 2024 as reported to the World Glacier Monitoring Service. Solid line is the cumulative balance, bars are the annual balance.**

Each of the last 15 years I have summarized the annual mass balance of alpine glaciers globally for the Bulletin American Meterological Society-State of the Climate report,. Below is the 2024 section on alpine glaciers with a few added figures.

ALPINE GLACIERS
M. Pelto

In 2024, all 58 global reference glaciers reported a negative annual mass balance. This is only the second year in the 1970–2024 period with all negative annual balances, following 2023. The global average annual mass balance based on equal weighting of 19 regions is −1.30 m water equivalent (w.e.), the most negative value in the record

The 2024 dataset of submitted glaciological observations includes 142 glaciers from six continents and 27 nations, with 140 reporting a negative balance and 2 a positive balance. In 2024, the mean annual mass balance of the 58 global reference glaciers was −1.44 m w.e. and −1.36 m w.e. for all 142 reporting glaciers. This is a similar result to 2023, which saw a mean reference glacier balance of −1.62 m w.e. and −1.35 m w.e. for all 116 reporting glaciers.

The 2024 regionalized global average of −1.30 m w.e. exceeds the previous most negative year in 2023, which saw a regional-ized global average of −1.25 m w.e. This makes 2024 the 37th consecutive year with a global alpine mass balance loss and the 15th con-secutive year with a regionalized global mass balance below −0.5 m w.e. The acceleration of mass balance loss indicates that alpine glaciers are not approaching equilibrium. The acceleration of mass balance loss is apparent regardless of datasets used to determine it, including glaciological, geodetic, altimetry, and gravimetric observations (The GlaMBIE Team 2025). The intercomparison assessment identified that global glaciers annually lost 273+26 gigatons (Gt) in mass from 2000 to 2023, with loss having been 36% greater in the second half than in the first half of this period (The GlaMBIE Team 2025).

In the European Alps, all 49 glaciers reported negative mass balances, with 45 losing over 1 m w.e. All 10 Icelandic glaciers had negative balances. In Svalbard, all seven had negative balances exceeding an exceptional loss of 1.25 m w.e. This was the result of near complete snow cover loss across most glaciers (Fig. 2.20) following record temperatures in August (see section 7f5 for details). Twelve of the 13 glaciers from Norway and Sweden had mass losses of more than 1.0 m w.e.

**High snow line persisted through the winter on Mount Everest glaciers.**

Across High Mountain Asia, 20 of 21 glaciers, reporting from seven nations, had negative balances. The highest average losses were in the Himalayas of Nepal and the lowest in the Pamir Range of Tajikistan.

In the Andes Mountains of South America, all 14 glaciers, reporting from five nations, had negative balances. Conejeras Glacier (Colombia), following a 5.04 m w.e. loss in 2023, was declared extinct in 2024. The daily hydrograph below this glacier changed from a predominanceof days with a purely melt-driven hydrograph from 2006 to 2016 to an increase in the frequency of days with flows less influenced by melt after 2016 (Morán-Tejeda et al. 2018).

All 16 glaciers in North America had negative balances. All four glaciers in Arctic Canada had mass balance losses under 1 m w.e. In western Canada and Washington and Montana (United States), all 16 glaciers reporting had losses exceeding 1 m w.e. The Ice Worm Glacier (Washington) was listed as extinct in 2023 after 40 years of continuous observations (Pelto 2024). In 2024, loss from the relict ice (ice that is no longer moving or part of a glacier) was 2.4 m and melt runoff below the glacier had decreased similar to Conejeras Glacier (Pelto and Pelto 2025). In Alaska, all three glaciers had mass balance losses. Davies et al. (2024) examined the Juneau Icefield, the most observed icefield in Alaska in terms of mass balance, and found an acceleration of mass loss with a doubling after 2010 compared to 1979–2010.

**Easton Glacier, Washington extensive retreat since 1990, with last five years being the most rapid. Terminus and mass balance surveyed annually and reported to WGMS.**

Alpine annual mass balance glaciological observations are reported to the World Glacier Monitoring Service (WGMS) by national representatives with a 1 December annual submission deadline. WGMS reference glaciers have at least 30 continuous years of mass balance observa-tion. Benchmark glaciers have at least a 10-year mass balance record and are in regions that lack sufficient reference glaciers. The combination of benchmark and reference glaciers is used to generate regional averages (WGMS 2023). Global values are calculated using a single averaged value for each of 19 mountain regions, limiting bias from observed regions (WGMS 2023). As this dataset expands, the annual values are reanalyzed and updated.

The lack of snow pack at the end of summer is evident across Edgeoya in Svalbard, blow a closeup of Digerfonna further illustrates with lettered points indicating new bedrock areas that are expanding amidst the ice cap.

Argentiere Glacier, France Rapid Snow Line Rise June 2026

On June 25, 2026June 26, 2026 By mspeltoIn france glacier retreat, Heat waves glacier melt1 Comment

**On June 1, 2026 the snowline is near the terminus of Argentiere Glacier at 2300 m, by June 24, 2026 the snowline has rise upglacier 3.3 km to 2700 m.**

The French Alps have expereienced a significant June heat wave that has driven a rapid rise in glacier snow lines. Rabatel et al (2013) examined the equilibrium line altitude (ELA) of glaciers in the region from 1984-2010. The ELA is the snowline at the end of the summer melt season. Rabatel et al (2013) found the average snow line of 3000 m on Trient Glacier, 2900 m on Tour Glacier, and 2800 m on Argentiere Glacier.

On June 1st and 7th 2026 the snow line on Argentiere Glacier was near the terminus at 2300 m, by June 24th the snow line risen to 2700 m. This is 100 m shy of the average end of summer snow line, with 25% of the glacier losing its snowcover in this period. In 2015 and 2017 the snowline reached a record height of 2950 m in late August. This snow line rose to 3000 m again in August of 2022 and to 2900 m in August 2023. The snow lines from these years are in images below

The high snow lines result in a limited accumulation zone and an expanded ablation area leading to mass balance losses and terminus retreat. Argentiere Glacier is a World Glacier Monitoring Service reference glacier, with the data indicated in the images below. The glacier advanced from the early 1960s to early 1990s and since driven by negative mass balances in all but one year this century has retreated ~ 1 km. The mass balance loss has exceeded 1 m in most years this century and will again this year.

**Annual mass balance reported to WGMS for Argentiere Glacier.**

**Terminus change reported to WGMS for Argentiere Glacier.**

**Argentiere Glacier snow line at end of 2015 melt season at 2950 m in Landsat image.**

**Argentiere Glacier snow line at end of 2017 melt season at 2950 m in Landsat image.**

**Argentiere Glacier snow line at end of 2022 melt season at 3000 m in Sentinel image.**

**Argentiere Glacier snow line at end of 2023 melt season at 2900 m in Sentinel image.**

Hofsjokull East, Iceland Loses all Snow Cover in 2025-Bedrock Expanding amidst Ice Cap

On September 22, 2025 By mspeltoIn climate change glacier retreat, Glacier Observations, iceland glacier retreat

**Hofsjokull East is snow free on 8-17-2025 in this false color Sentinel image. This leads to ice melt, thinning and bedrock expansion at Point A-D.**

Hofsjokull East, Iceland is a small ice cap east of Vatnajokull with a summit elevation of 1100 m. In the last decade the snow line has often been above the ice cap. The ice cap had an area or 4.97 km² in 2003 declining to 2.51 km² in 2023 (Iceland Glacier Viewer). In 2024 all 10 glaciers in Iceland had significant mass loss (Pelto, 2025).

In August 2020 the ice cap has lost nearly all of its snow cover, this occurred again in 2023 and 2024. The result in 2025 when the ice cap again lost all its snowcover, is significant glacier surface melt and thinning. This leads to expansion of bedrock. At Point A there has been rapid expansion of the bedrock knob. At Point B and C new bedrock has been exposed and rapidly expanded. At Point D a bedrock rib at the edge of the ice cap has spread into the ice cap.

The lack of snow cover indicates the ice cap no longer has an accumulation zone and cannot survive. In 2025 the ice cap area is 2.10 km² . Ice cap area has declined by ~60 % in the last 22 years. The story here is similar to that at the larger Prándarjökull 10 km to the northeast. The summer of 2025 in Iceland was exceptional beginning with a May heatwave, followed by a July heatwave. The May heat wave led to high snow lines as summer began on Vatnajokull.

Hofsjokull East is nearly snow free on 8-14-2020 in this false color Sentinel image. Contrast the area of bedrock at Point A-D to the 2023 and 2025 images.

Hofsjokull East is nearly snow free on 9-3-2023 in this false color Sentinel image. Point B and C now have evident bedrock areas.

Kokanee Glacier 2021: slash and burn

On September 28, 2021April 22, 2024 By mspeltoIn climate change glacier retreat, glacier climate change, Glacier Observations1 Comment

The southwest side of Kokanee Glacier from the ridge with Cond Peak at the Right and Sawtooth Ridge at center.

By Ben Pelto, PhD, UBC Mitacs Elevate Postdoctoral Research Fellow

Since 2013 I have been working on the Kokanee Glacier. Located just outside of Nelson in southeastern British Columbia (BC), the Kokanee Glacier is due north of the Washington-Idaho border. This work began as part of a five-year study of the cryosphere in the Canadian portion of the Columbia River. This project was carried out by the Canadian Columbia River Snow and Glacier Research Network — spearheaded by the Columbia Basin Trust. The glacier research, which included the Kokanee Glacier, was led by my former PhD supervisor at the University of Northern British Columbia Dr. Brian Menounos and myself. At the culmination of the project, we published a technical report, and a plain language summary of that report. When the five-year project officially ended in 2018, I learned of a BC Parks program called Living Labs, which offers funding for climate change research in BC Parks, particularly research which documents change and guides protected area management. With Living Labs funding in 2019-2021, I have kept the annual mass balance trips going — now a continuous nine-year record — and a winter mass balance trip in 2021. In conjunction with this, Brian Menounos has secured continued funding (continued from our 5-year project) from BC Hydro for LiDAR surveys of the glacier every spring and fall. These surveys are carried out by the Airborne Coastal Observatory team from the Hakai Institute.

During the 2021 spring trip, we found that the Kokanee Glacier had an average snow depth of 4.4 meters. Using snow density measurements collected with a snow-corer, we found that the winter balance for 2021 was 1.91 meters water equivalent (m w.e.). This value was lower than the 2013-2020 average of 2.18 m w.e. (Pelto et al. 2019).

Ali Schroeder probing snow depth on the Kokanee Glacier while Joel McBurney and Drew Copeland look on.

With a below average winter balance, 2021 would need to feature a cool summer. Instead, multiple heat waves occured, with temperature records being broken across the province. Wildfires burned all over BC and the neighboring US states of Washington and Idaho, swamping the region in smoke for weeks on end. Rather than mitigate for a slightly-below-normal snowpack on the Kokanee, summer 2021 took a blow-torch to glaciers across the region.

We hiked into the Kokanee Glacier on September 12, stopping under a boulder to wait out proximal booms of thunder and flashes in the clouds. We got pelted with bursts of both hail and graupel, and soaked in the rain, before gingerly working our way up boulder field and talus that is climbers route up the Keyhole to the Kokanee Glacier. Like the satellite imagery had shown, there was no snow in sight on the glacier — bare ice only. Instead of my usual camp on the snow, we chose a climbers bivy site to set our tent.

Camp in the Keyhole — a total lack of snow forced us to skip camping on-glacier.

Stepping out onto the glacier, we immediately ran into difficult terrain, crevasse bridges of snow or firn had collapsed, leaving bedroom-width crevasses gaping open, necessitating an exercise in maze navigation. Our first stop was a stake at 2600 m which typically retains snow (50 to 100 cms), but this year had lost 1.6 meters. In fact, two stakes drilled at the site in 2015 and subsequently buried by snow had melted out, demonstrating that all snow/firn from the intervening years had been lost. This observation clued me in to the magnitude of melt to expect this year.

The first stake visited, showing 1.6 m of melt

Travel on the glacier was more challenging in spots, but overall faster, as the total lack of snow meant that most crevasse bridges were gone, requiring less probing of crevasse bridges and roped-travel. Later, using a satellite image from the dates of our visit, I mapped the retained snow cover, limited to two tiny patches high on the glacier’s east side. The accumulation area ratio (AAR), or the ratio of snow cover to bare ice/firn was <0.01, meaning that under 1% of the glacier was covered in snow.

The upper reaches of Kokanee Glacier to Cond Peak (2800 m) with no retained snow in 2021. Bare ice is exposed on the lower half of the image, and firn, or multi-year snow above

Near infrared-Red-Green 30 cm resolution ortho image of Kokanee Glacier from the Hakai Geospatial/ACO team on Sept. 2, 2021. Note how badly crevassed the glacier is, most crevasses are exposed with no retained snow. The white color and mottled appearance over the upper glacier is a skiff of overnight snow just a few centimeters thick that melted off the next day. Also note bare ice patches exposed under formerly perennial snow patches that have shrunk in recent years and now are disappearing.

Visiting the toe of the glacier, our lowest stake indicated just under 5 m of ice melt, double that of 2020. In May, this location had 3 m of snow; the combined melt of snow and ice (loss of winter snow and glacier ice) is termed the summer mass balance, and at this site was -6.2 m w.e., far higher than the usual -4 m w.e. I also noticed that much of the thin ice along the margin of the toe was gone, and a little rock nunatak (rock island) that appeared in 2015 (images below) became a bite out of the glacier rather than a island. We estimated that the toe experienced 60 m of retreat. Over the past 5 years, the Kokanee has lost an average of 16 m in length annually. Expecting to see above average thinning and retreat, I was still startled to see how diminished and thin the toe looked.

2015: a small hole forms in the glacier margin above the toe, Jesse Milner in the foreground

A week prior to my field visit, the Hakai Institute ACO team flew a LiDAR survey of the Kokanee Glacier as part of their work with Brian Menounos at UNBC. Comparing this year’s glacier surface with that from last year’s survey, Brian found a whopping 2.55 m of thinning. After mapping the glacier facies (ice/firn/snow) to represent on the density of the observed thinning, this equates to a glacier mass balance of -2.16 m w.e., higher than the previous record loss of -1.20 m w.e. in 2015.

LiDAR-derived height change 2020 to 2021 from 1 m resolution DEMs from Brian Menounos and the Hakai Institue ACO team. The black line is the 2021 glacier outline, note the bite out of the glacier above the toe to the NE corner of the glacier. Small red patches off-ice are seasonal snow patches losing mass. Points represent mass balance observation locations.

Kokanee Glacier terminus from 2015 to 2021. 140 meters of retreat for 23 m/yr. Data in the GIF are from Hakai Institute and Brian Menounos of UNBC ACO glacier surveys.

Back home, I crunched the numbers from our glaciological observations of mass balance (consisting of 14 ablation stakes this year) and calculated a mass balance of -1.97 m w.e. With Brian, I published a paper in 2019 (Pelto et al. 2019) comparing glaciological (field) and geodetic (LiDAR) mass balance estimates and found them to be similar — if some factors like snow and firn density were carefully considered. The small difference between estimates is likely due to timing (the LiDAR mass balance is from 8/26/2020 to 9/3/2021, while the field mass balance is 9/12/2020 to 9/13/2021), and that there was a skiff of fresh snow (likely 5-10 cms) on the glacier during the 2020 LiDAR survey.

Kokanee 2021 glacier mass balance. Blue dots are observations. The boxplots show the 100 m bins used to estimate glacier-wide mass balance (median line in black, mean dashed grey line). The grey bars depict the area of the glacier for each 100 m elevation-band

Seasonal and annual mass balance for Kokanee Glacier from LiDAR and glaciological measurements for each balance year from 2013 to 2021 with 2σ uncertainties.

In 2017, I visited the Kokanee Glacier to measure it’s ice thickness using ice-penetrating radar. I found that the glacier on average was 43 m thick using my measurements to tune a glacier model. I published these results in the Journal of Glaciology (Pelto et al. 2020). In the five years since that work, the glacier has lost over 4.8 m of total thickness. That equates to a loss of over 11% of its total volume. 2021 alone wasted away 6% of the glacier’s total volume — an eye-watering number for a single year.

Cumulative mass balance for Kokanee Glacier 2013-2021 from both field and LiDAR measurments. LiDAR-derived mass balance began in 2016.

The heat of 2021 was an outlier, but years like 2021 and 2015 take a toll on the glaciers. Currently, glaciers in western North America are losing around 0.75 m of thickness per year (according to my work in the Columbia Basin (Pelto et al. 2019) and work by Brian Menounos for all of western North America (Menounos et al. 2018)). The better years for Kokanee Glacier (2016 mass balance: +0.12 m w.e.) pale in comparison. That meager surplus was lost the very next year (2017).

Herein lies the issue, positive mass balance years in recent decades are not large enough to offset even average years; hot dry summers take years off the lifespan of glaciers across western North America.

Losing 6% of it’s total volume in 2021, the best we can hope for Kokanee Glacier is a few near-neutral or positive mass balance years to cover back up the exposed firn, to keep the glacier albedo from becoming too dark and increasing the rate at which ice can melt.

Art and Science on the Easton Glacier: Reflections from the NCGCP 2020 Field Season

On March 30, 2021April 23, 2024 By mspeltoIn North Cascade Glaciers

The field team at Camp discussing science communication and gazing at the Easton Glacier. Photo by Jill Pelto

By: Cal Waichler, Jill Pelto, and Mariama Dryak.

It is the evening of Aug. 9th, 2020 and six of us are camped near the terminus of Easton Glacier. The sun has dropped below the moraine ridge above camp and a chilly breeze has forced us to put on layers. We are enjoying dinner cooked on our camp stoves, discussing what we observed on the ice today. The toll of climate change on Easton Glacier, on the southern flank of Mount Baker, is impossible to escape. We are here to both measure this change and communicate what it means.

Within our team of six, four of us are trained as scientists, and all of us highly value creative science communication. This passion can manifest as art (painting, printmaking, sketching), writing, podcasting, blogging or video-making. We all appreciate that exercising creativity with others can provide us with a unique context for communicating about glaciers and climate change.

**Cal creates at Columbia Glacier–sketching and taking notes to capture the power of our lunch spot that day. Photo by Mariama Dryak.**

**Jill paints the icefall. Photo by Mariama Dryak.** .

The Easton Glacier is large and stretches up to 2950 m elevation. We are here to monitor its health for the 31st consecutive year: its snow coverage, snow depth, terminus retreat, change in surface profile, and its annual mass balance (snow gain vs. snow loss). Easton Glacier is one of the forty-two World Glacier Monitoring Service reference glaciers, meaning it has 30+ consecutive year of mass balance observations, qualifying it for this select group. To learn more about this glacier over time, check out https://glaciers.nichols.edu/easton/ and a previous Easton Glacier update.

While we are at Easton Glacier to measure annual changes, we also see this landscape in the realm of both art and science. From the artistic lens we may note the same things that we do during research: the debris covering the retreating terminus, the crevasses melting down and getting shallower. But we also notice the beauty of these structures, how the crevasse patterns splay out across a knob, and the parallel lines preserved on a serac – recording five years of accumulation like rings on a tree. Observation is a theme in both art and science. We train our eyes to notice things in different ways, to pay attention to certain details. We are able to document these changes in our field notebooks, but also in sketchbooks, journals, photos, and videos.

The records of beauty stored in our sketchbooks serve as a qualitative reminder of what this landscape looks and feels like. In the process of depicting the landscape at the end of a field day, we paint our joy and exhaustion onto the page. In the moment, this act uncovers more details and allows us to reflect. Weeks later when we are off the mountain, we reopen our water-logged, dirt-streaked pages and are taken back to that place where we were. Field sketches, poems and paintings help us capture the emotion of moving through and attempting to understand sublime spaces. They are a vital link between our memories and sharing the meaning of our experience with others. They are also a deliberate recording of time and place — a kind of data in their own right.

The experience of working in this environment is memorable to us — we get to observe a plethora of crevasses, dozens of meltstreams, and strikingly beautiful colors. We can feel a range of excited, inspired, and nervous emotions throughout the day. For us, this experience is giving us the emotional context to our research: being present we can understand that “why”. That reason why the work matters not just for scientific knowledge, or the local ecosystem, but also for humanity. The science results alone can share the data that underlies that, but they might not always connect with other people in a way that elicits that comprehension. Our creative communication through writing and art can elicit that deeper, emotional understanding of why it’s important to preserve and protect these places, and why we need to understand the amount of change that will occur to the climate and ecosystem. Our collection of art shares stories about Easton Glacier in ways that connect with the science, and also go beyond it.

This summer we all felt especially fortunate to be in the North Cascades. Covid-19 has kept us all so isolated and often indoors. The chance to work on the glaciers and live at their feet for two weeks gave us back some of the breathing room we lacked in 2020 – a lucky opportunity indeed.

Cal’s Art – clairewaichler.com

Mariama’s website – Let’s Do Something Big

Jill’s Art – jillpelto.com

AGU Poster Hall-Cryosphere Perspectives

On December 13, 2018April 25, 2024 By mspeltoIn Glacier Observations

The American Geophysical Union Fall meeting’s Cryosphere section continues to grow as seen in the Poster hall. The poster hall is where most of the research is presented and is dominated by student work. Here are some examples of this work.

Erin McConnell, UMaine and others examined shallow ice cores from glaciers in the St. Elias Mountains of Canada’s Yukon as part of a project to reconstruct past climate variability using ice cores. The study quantified the relationships between meteorological data and ice core records in the St. Elias. The focus was on Icefield Divide, 2,900 m and Eclipse Icefield, 3,017 m. In June 2018 they extracted two ice cores (10 m and 20 m) from Divide. at Eclipse. In addition they did a 400 MHz radar transect at Divide which showed a strong reflectance at ~30 m depth, that likely indicates a firn aquifer, that develops from meltwater percolation and causes the isotope signal to deteriorate below the 2017/2018 snowpack (~6 m depth). GPR data from Eclipse Icefield shows no evidence of an aquifer, suggesting the process in the St. Elias may occur only below ~3,000 m elevation. The results pictured contrast annual accumulation at the two sites.

Andrew Nolan and others, from UMaine examined the surging Turner Glacier. Surge glaciers exhibit a short active phase of rapid ice velocity followed by a longer quiescent phase of slower flow. Turner Glacier is in the St. Elias Mountains, Alaska adjacent to Hubbard Glacier. Using a Landsat archive for the 1984 to 2017 period they found five previously unexamined surge events. Surge events occurred in 1985-1986, 1991-1993, 1999-2002, 2006-2008, and 2011-2013. This indicates a ~5-year surge repeat interval. They used ASTER digital elevation models from the 2006-2007 and 2011-2013 to show mass build up in the reservoir zone which initiates the surge, prior to the surge. The surge then redistributes the mass to the terminus zone. The reservoir zone surface elevation increased 50 meters preceding the 2005-2008 surge event and then subsided 100 meters and the terminus zone rose 75 meters. The image below indicates thinning in red upglacier and thickenning in blue downglacier.

Wiiliam Kochtitzky, UMaine and others examined Donjek Glacier a surging glacier in the St. Elias range, Yukon. They examined velocity and ice elevation changes since 2000 on this 65 km long glacier to understand the beginning and end of surges. The glacier has surged eight times since 1935 with a 12 year repeat rate. The glacier has had a negative mass balance and has retreated 2.5 km since ~1874. Each successive surge of Donjek Glacier has featured a more limited advance than the previous. This akin to waves on a falling tide. To map ice motion before, during, and after the 2001 and 2013 surge events they used Landsat scenes to measure monthly ice velocity. During these events they observed maximum uplift of ~75 m in the terminus (receiving) zone and maximum subsidence of ~65 m in the reservoir zone, 8-21 km above the terminus. The most negative mass balance occurred in the lower 32 km of the glacier after the 2013 surge, with Donjek losing an average of -6.65 m year. The upper 40 km of the glacier is not involved in the surge. This glacier has important implications for larger ice masses, such as ice streams, that could have strong negative mass balances even if they surge and/or are land terminating superimposed on the surge cycle.

Pacifica Askitrea Takata-Glushkoff of University of Alaska Fairbanks and others examined the glacier dynamics of High Mountain Asia (HMA) glaciers. She used a glacier evolution model to account for geometry changes from surface mass-balance feedback. Previously used scaling methods are simpler than flow models, but they do not account for glacier thinning. Glaciers typically show most thinning at lower elevations and least thinning at higher elevations, with various factors influencing these relative thinning patterns. She investigated glacier thinning variability with elevation, in order to account for retreat . Using geodetic data from 170 glaciers in the High Mountain Asia region, they determined for each glacier how normalized changes in ice thickness vary with elevation. They investigated whether those normalized curves are impacted by factors such as glacier area, slope, aspect, debris cover, length, and glacier terminus elevation. Results indicate that shallow slopes and less debris cover are both associated with more relative glacier thinning toward the glacier terminus.

Andrew Hengst and others from Appalachian State University mapped pro-glacial lakes in Northwestern North America to better understand . They used a semi-automated algorithm to delineate proglacial lakes and analyze proglacial lake area change over the satellite record to investigate lake growth rates and physical controls. This approach allows robust identification and analysis of proglacial lake area change utilizing the complete Landsat satellite record . The use of an object-based processing algorithm enabled automatic location and tracking proglacial lakes over large spatial and temporal scales to increase understanding of the dynamics of these complex and changing systems, such as in the examples below that show lake area change. The algorithm had the most difficulty with lakes that had high suspended sediments and debris covered termini with a complex ending in the lake.

A Voice for Glaciers at COP21

On November 27, 2015May 2, 2024 By mspeltoIn climate change glacier retreat, glacier climate change, Glacier Observations

During the last six years From a Glaciers Perspective has published 520 Posts examining the response of glaciers to climate change. No hyperbole has been needed to use words such as disappear, fragmented, disintegrated, and collapse. Glacier by glacier from the fragmentation of glaciers to the formation of new lakes and new islands has emphasized the changing map of our world as glaciers retreat. The story details change, but the story remains the same; glaciers are poorly suited for our warming climate, and their only response is to hastily retreat to a point of equilibrium, which many will not attain, and some have already ultimately failed. The Gallery below is a mere snippet of the changes that are occurring. These are illustrations of why our paper this year led by the World Glacier Monitoring Service team was titled Historically unprecedented global glacier decline in the early 21st century. As the UN Climate Change Conference 2015 in Paris, COP21 begins, since no glaciers are invited, there story must be told in pictures, data and our words.

Data: World Glacier Monitoring Service Mass Balance Time Series for Alpine Glaciers.

Pictures

Words:

After 34 consecutive summers working on glaciers, there is occasion to speak as more than just a scientist, since glaciers do not have a voice people hear.