Burroughs Glacier, Alaska Down to Last 1%

On February 2, 2023April 20, 2024 By mspeltoIn alaska glacier retreat, glacier climate change1 Comment

Burroughs Glacier in 1986 and 2022 Landsat images. The red arrow marks the west margin and the yellow arrow the east margin in 1986. Yellow dots mark the outline of the glacier in 2022. Glacier area declined from 12.5 km² to 1.5 km² during this 36 year period.

Burroughs Glacier in Glacier Bay National Park, Alaska has been retreating without pause since 1892 when it was part of the Muir Glacier complex. The glacier is unusual in that it has not had an accumulation zone over the last century, where snow persists through the year. Without an accumulation zone a glacier cannot survive (Pelto, 2010). Mickelson (1971) summarized the retreat of the glacier from 1892-1960. In 1892 the Burroughs ice plateau was assessed as a 10 km by 25 km ice cap. By 1960 it had thinned by as much as 750 m and its calving margin had retreated 27 km.. By the 1970’s the glacier was essentially stagnant (Molnia, 2008). In 1982 I briefly visited the western terminus, which provided a still imposing slope, made more so by the rain and clouds lowering onto its surface.

Here we examine the glacier in Landsat imagery from 1986 to 2022 to illustrate the retreat, the lack of snowcover and the thinning. In the 1948 map of Burroughs Glacier, the glacier is 12.1 km long, and much of the glacier is already stagnant, the glacier has both a north and south terminus, purple arrows. To the west of Burroughs Glacier is Plateau Glacier (P).

Burroughs Glacier in 1948 USGS map.

In 1948 Burroughs Glacier has an area of 22 km² and is 12.5 km long, with the crest of the glacier at ~1500 feet. In 1986 Burroughs Glacier has an area of 12.5 km² and has no snowcover by mid-summer. The glacier terminates in proglacial lakes at both the north and south terminus red and yellow arrow respectively, and is 9 km long, purple arrows indicate 1948 terminus. By 1986 Plateau Glacier has only three small remnants marked by P, surrounding these vegetation is still limited, with considerable expanse of bare glacial sediments. By 2003 Plateau Glacier is gone and vegetation is filling in most of the area that was still bare sediment in 1986. In 2003 Burroughs Glacier again lacks any snowcover. The southern terminus has retreated 2.2 km from the lake, and the northern terminus has retreated into a second lake basin. The glacier is 6.3 km long, half of its length in 1948. In 2004 snowcover is again lacking anywhere on the glacier. In 2010 snowcover is lacking and retreat has continued shrinking the glacier to 5.4 km in length. The glacier was assessed with an area of 2.8 km² and a median elevation of 313 m (1025 feet) by GLIMS. In 2013 the glacier lacks snowcover in this September Landsat image even though snow has returned to the surrounding mountains. This indicates how far below the snowline the glacier lies. Portions of a glacier are supposed to be the first locations that receive snowcover. The terminus has continued to retreat and the glacier was 4.6 km long in 2013. The northern terminus was retreating into a third basin of the proglacial lake. Vegetation has reclaimed almost all of the Plateau Glacier area and has reclaimed the region deglaciated by Burroughs Glacier before 2003. By 2022 the glacier area has been reduced to 1.5 km², this is just 12% of its area remaining from 1986 and 1% of the 1892 area. The length of the glacier in 2022 is 2.3 km, only 50% of the lenght just a decade ago, and ~20% of the 1948 length.

Thinning of this glacier from 1948-2016 is evident from a comparison of topographic maps. Thinning in remaining glacier are averages 225 m during this period, that is a rate of ~3.3 m/year. Larsen et al (2007) had found a thinning rate of ~3 m/year for the 1948-2000 period.

Overlay of 1948 (blue labeled contours) and 2014 elevation map (Brown labeled contours) for Burroughs Glacier.

Burroughs Glacier has not been in equilibrium with climate since the end of the Little Ice Age. Its retreat has been hastened by the rising snowline of the last decade note by Pelto et al (2013) on Brady Glacier. This glacier area has declined by 88% since 1986, with volume loss being even larger. Retreat usually increases as elevation declines and as the size of the remnant ice declines. There is no debris cover or persistent snowcover to slow the loss. Thus, it seems likely this glacier will be gone within 25 years. The 2011 Google Earth image at bottom indicates no snow, the reduced albedo from the dirty surface and a few crevasses near the margin that are collapse features. This is unlike nearby glaciers that are retreating significantly but not disappearing, like Brady Glacier, Geikie Glacier, Yakutat Glacier and Riggs Glacier.

1986 Landsat image of Burroughs Glacier. The purple arrows mark the 1948 margin, red arrow the west margin in 1986 and the yellow arrow the east margin.

2003 Landsat image of Burroughs Glacier. The red arrow marks the west margin in 1986 and the yellow arrow the east margin.

2004 Landsat image of Burroughs Glacier. The red arrow marks the west margin in 1986 and the yellow arrow the east margin.

2010 Landsat image of Burroughs Glacier. The red arrow marks the west margin in 1986 and the yellow arrow the east margin.

2013 Landsat image of Burroughs Glacier. The purple arrows mark the 1948 margin, red arrow the west margin in 1986 and the yellow arrow the east margin in 1986, pink arrows the 2013 margin.

2022 false color Sentinel image of Burroughs Glacier. The ice is dirty but not debris covered at this point.

Suru Basin, Ladakh India Glaciers Bare of Snowcover in August 2022

Suru Basin glaciers in 1998 and 2022 Landsat images. Red arrow marks the 1998 terminus location, yellow arrow the 2022 terminus location. S=Shafat Glacier, D=Dilung Glacier. Glacier 1-4 are unnamed glaciers that lost almost all snowcover in 2022.

Glaciers of the Suru Basin, draining the Ladakh Range, a drier region of the Himalaya, was significantly by the 2022 pre-monsoon and monsoon season warmth. Here we focus on a group of glaciers near Shafat and Dilung Glacier that lost snowcover in 2022. We also look at the retreat of Shafat and Dilung Glacier. Shafat Glacier occupies the northeast flank of Nun Kun Peak in Ladakh India and drains into the Suru valley. The main valley glacier has suffered from detached tributaries leading to terminus area stagnation (Pelto, 2021). Dilung Glacier retreat has led to an expanding proglacial lake. Shukla et al (2020) identified an increase in annual temperature has driven a 6% loss in regional glacier area and a 62% expansion in debris cover from 1971-2017. Here we compare Landsat imagery from 1998-2022 to identify this glaciers response to climate change.

In 1998 the terminus of Shafat Glacier was at the red arrow near a junction with a key tributary, with clean active ice reaching to the terminus. By 2022 the active ice is 2.5 km upglacier from this point at the yellow arrow, though there is stagnant debris covered ice below this point. Dilung Glacier in 1998 terminates in a 1.1 km long proglacial lake. By 2022 the glacier has retreated 900 m, resulting in a 2.0 km long lake. Rashid and Majeed (2018) indicate nearby Drang Drung Glacier has retreated 925 m since 1971, with a sharp increase after 2014.

For an alpine glacier to have a balanced annual budget it has to be 50-60 snowcovered at the end of the melt season. On Sept. 1, 2022 there are four glaciers 1-4 in this region that have 0-10% snowcover left. The snowcover is above 5300 m. This is illustrative of significant mass losses in 2022. On Dilung Glacier and Shafat Glacier the snowcover is ~20% and is confined to the regions above 5300 m. There is some cloudcover over the top of the Shafat Glacier in the 9-1-2022 Landsat image.

Suru Basin glaciers in September 1, 2022 Landsat image. Glacier 1-4 are unnamed glaciers that lost almost all snowcover in 2022. S=Shafat Glacier, D=Dilung Glacier. The snowline is above 5300 m.

Alpine Glaciers Section-State of the Climate 2021

On August 31, 2022April 20, 2024 By mspeltoIn glacier climate change, Glacier Observations

The 32nd annual State of the Climate report was published today. For the 14th year I have written the Alpine Glacier section chronicling their response for the the hydrological 2020/21 utilizing the World Glacier Monitoring Service (WGMS) data sets. WGMS reference glaciers (30+ years of continuous observation) experienced a mass balance loss of -900 mm w.e., compared to -700 mm w.e. in 2019/20. From 1970-2021 the eight most negative mass balance years were recorded after 2010.

Figure 1. illustrates glacier mass balance for the WGMS global reference glaciers with more than 30 continued observation years for the time-period 1970-2020. Global values are calculated using a single value (averaged) for each of 19 mountain regions in order to avoid a bias to well observed regions.

In 2021, a negative annual mass balance was reported from 31 of the 32 reference glaciers reported to the World Glacier Monitoring Service (WGMS). The mean annual mass balance of the 32 reference glaciers reporting is -900 mm w.e., this includes data from 12 nations on four continents. This value is not the final regionally averaged global value. This will make 2021 the 34^th consecutive year with a global alpine mass balance loss, and the 13th consecutive year with a mean global mass balance below -500 mm w.e..

The rate of thinning increased from –527 mma⁻¹ for 2000-2009 to – 896 mma⁻¹ for 2010-2019 (WGMS, 2021). This agrees well with the satellite survey of 200,000 alpine glacier by Hugonnet et al (2021) who identified a thinning rate excluding ice sheet peripheral glaciers of 360 ± 210 mma⁻¹ in 2000 to 690 ± 150 mma^-1 in 2019. Alpine glaciers lost a mass of 267 ± 16 Gta^-1from 2000-2019, equivalent to 21 ± 3 per cent of the observed global sea-level rise (Hugonnet et al, 2021). More frequent and intense heat waves continue to take a toll on alpine glaciers.

All 17 reporting glaciers in the Alps had a negative mass balance averaging – 682 mm in 2021. In Austria in 2020, of the 92 glaciers with annual terminus observations 85 (93.4%) withdrew and seven remained stationary (Lieb and Kellerer-Pirklbauer, 2021). This retreat trend will continue in 2021, with another year of mass balance loss.

In Norway the six reporting glaciers all had a negative mass balance yielding an average mass balance of -671 mm in 2021. On Svalbard the mean loss of the four reporting glaciers was -227 mm. Iceland completed surveys of nine glacier, all nine had negative balances with a mean mass balance of -1160 mm.

In the Western Canada and the United States and Washington all 14 glaciers observed in 2021 had a negative mass balance averaging -1635 mm. The exceptional heat wave during late June and early July set the stage for the large glacier mass loss. In Alaska three of the four glaciers had a negative mass balance with a mean annual balance of -528 mm.

Upper portion of Easton Glacier with a month left in the melt season

In South America, 2021 mass balance data were reported from three glaciers in Argentina, two glaciers in Chile, and one in Columbia, all were negative with a mean of -861 mm. This is greater than the 2000-2018 average loss observed in the Andes of −720 ± 220 mma^-1 (Dussaillant et. al., 2019).

In the High Mountain Asia fifteen of eighteen glaciers reported negative balances in 2021. The average mass balance was-468 mm. Early winter of 2021 was warm and dry across the Himalayan Region. This was capped off by record warmth in the Mount Everest region leading to the snow line on glaciers rising and snow free glaciers up to 6000 m (Pelto, et al., 2021). This illustrates that the ablation season no longer always ends when winter begins. The importance of winter conditions was further noted by Potocki et al (2022) who report on an ice core drilled on South Col Glacier on Mount Everest at 8020 m revealing a contemporary sublimation driven thinning of ~2000 mma^-1.

References

Dussaillant, I., Berthier, E., Brun, F., Masiokas, M., Hugonnet, R., Favier, V., Rabatel, A., Pitte, P.and Ruiz, L.,2019: Two decades of glacier mass loss along the Andes. Nat. Geosci. 12, 802–808. https://doi.org/10.1038/s41561-019-0432-5

Hugonnet, R., McNabb, R., Berthier, E. et al 2021: Accelerated global glacier mass loss in the early twenty-first century. Nature 592, 726–731. https://doi.org/10.1038/s41586-021-03436-z

Lieb, G.K. and A. Kellerer-Pirklbauer 2021: Sammelbericht über die Gletschermessungen des Österreichischen Alpenvereins im Jahr 2020. Letzter Bericht: Bergauf 2/2020, Jg. 75 (145), S. 6–15, https://www.alpenverein.at/

Pelto, M.; Panday, P.; Matthews, T.; Maurer, J.; Perry, L.B., 2021: Observations of Winter Ablation on Glaciers in the Mount Everest Region in 2020–2021. Remote Sens. 13, 2692. https://doi.org/10.3390/rs13142692.

Potocki, M., Mayewski, P.A., Matthews, T. et al, 2022: Mt. Everest’s highest glacier is a sentinel for accelerating ice loss. Nature Clim. Atmos. Sci., 5, 7. https://doi.org/10.1038/s41612-022-00230-0.

WGMS 2021: Global Glacier Change Bulletin No. 4 (2018-2019). Zemp, M., Nussbaumer, S. U., Gärtner-Roer, I., Bannwart, J., Paul, F., and Hoelzle, M. (eds.), ISC(WDS)/IUGG(IACS)/UNEP/UNESCO/WMO, World Glacier Monitoring Service, Zurich, Switzerland, 278 pp., doi:10.5904/wgms-fog-2021-05.

World Glacier Monitoring Service: Fluctuations of Glaciers (FoG) Database

DOI for current scientific data (Identifier): 10.5904/wgms-fog-2021-05

https://wgms.ch/data_databaseversions/

Whitney Glacier, Mount Shasta snow free again in 2022

On August 26, 2022April 20, 2024 By mspeltoIn glacier climate change4 Comments

Whitney Glacier on August 25, 2022 in Sentinel image. Green arrows separation points, yellow arrows remaining snowpack

The summer of 2021 proved to be catastrophic for Whitney Glacier on Mount Shasta, California in terms of volume loss, ~15% leading to long term impacts, such as the 50% area reduction and 1000 m retreat since 2005. The glacier lost 100% of its 2021 snowpack and was in the process of separating into three segments. In 2022 it was important for the glacier to offset some of this loss with a healthy retained snowpack through the sumer. Unfortunately by mid-August it is evident that the glacier will again be snow free by end of summer in 2022. This will continue the rapid area and volume loss and continue the separation process.

Here we examine local weather records and Sentinel imagery to illustrate the conditions in 2022. The winter of 2022 started off well with near record December snowfall, followed by limited snowfall and temperatures averaging +3 C in Shasta County, until another big month in April. The results was well below average snowpack in early spring. A cool wet April and May preserved the limited snowpack. July experienced average temperatures 2.2 C above normal in Shasta County (NCEI-NOAA County Mapping)

Whitney Glacier in Sentinel images from 8-30-2020, 8-31-2021 and 8-15-2022. Green arrows separation points, yellow arrows remaining snowpack and T=terminus location,.

Fragmentation of the glaciers is evident in the comparison from 9-4-2018 and 9-4-2022, there are seventeen fragments left, six fragments that have melted away also.

A comparison of August snowcover from 2020-2022 illustrates the small patch that remained in 2021, yellow arrow, and the small patches left in mid-August of 2022. The ongoing separation is evident at two locations sho.w with green arrows. From August 2020-August 2022 the glacier area has declined from 0.72 km ² to 0.57 km ² a ~20% loss. The width of the glacier at the two arrows has been reduced by ~50% to 50 m at the lower elevation of 3250 mand 100 m at the upper elevation of 3600 m. A key issue this summer again has been the high temperatures in July and August, in particular the high minimum temperatures, preventing the snow surface from freezing at night and shutting off the melt. At Gray Butte, 2450 m, the remote weather station indicates a period from July 9-August 7 where the temperature never dropped below 10 C (50 F).

Gray Butte summer temperatures at an hourly interval (Data from Mount Shasta Avalanche Center)

The velocity in two primary icefalls above each of the separation points is declining based on the NASA_IT’s LIVE application. The reduced flux combined with high summer melt in 2021 and 2022 will continue to accelerate the separation.

Velcoity data for two icefall locations on Whitney Glacier 2019-early 2022, from NASA_ITs-LIVE application

Whitney Glacier Icefall at the green arrow seen on 8-15-2022 ( Mount Shasta Avalanche Center). Note the thin upper arm of the glacier.

Alpine Glacier Incompatibality with Heat Waves

On May 5, 2022April 20, 2024 By mspeltoIn glacier climate change, Glacier Observations, Uncategorized

**Bare glacier ice exposed with months left in the melt season enhances melt. Down slope ice bands and surface roughness on Sholes Glacier.**

Heat waves and glaciers don’t usually go together; however, in the last several years an increasing number of heat waves have affected alpine glacier regions around the world. This is true from Arctic Canada to the Himalayas from the Andes to Alaska. Here we review a number of these heat waves from 2018-2022, that I have been involved with assessing and observing. In particular heat waves leave a greater portion of the glacier snow free, which enhances melting and mass balance losses. This is most pronounced when the heat wave occurs prior to or early in the melt season exposing bare glacier ice for the bulk of the melt season. This occurred in summer 2021 in the Pacific Northwest, in summer 2022 in the Central Andes of Chile and Peru, and during the pre-monsoon season in 2022 in the Himalaya. In the summer of 2022 heat waves impacted the glaciers of Svalbard and Europe. In the summer of 2023 the Central Andean glaciers have again been stripped of snowcover.

Lowell Glacier in Landsat images from 7/4, 7/26 and 8/11 with Sentinel images from 7/22 . The snowline is shown with purple dots. Point A-F are fixed reference locations. The snowline migrated upglacier 20 km and 300 m in elevation. A significant snow swamp is between the yellow and purple dots on 7/26, that was not present on 7/22.

The beginning of this “wave” of observations of heat wave impacts on glaciers, was on Lowell Glacier, Yukon where a large snow swamp formed in a matter of days during a Yukon/Northwest Territories Heat Wave. On July 26, the slush covered an area of more than 40 square kilometers, with the rapid development of such a large melt area on Lowell Glacier coinciding with four days where daily temperatures at nearby Haines Junction (~60 km northeast of the glacier) reached 29 degrees Celsius. The only way to generate an extensive snow swamp is to have the snow saturated with water all the way to the surface NASA’s Earth Observatory (NASA EO).

Taku Glacier transient snowline (purple dots) in Landsat images from 7/21 and 9/16/2018.

This same heat event led to the observation that the snow lines on Taku Glacier in Alaska were the highest they had been since tracking began in 1946, 200 m higher than previously observed, with the snow line rising +10 m/day during the heat wave (Pelto, 2019).

Fork Beard (F) and Nerutusoq Glacier (N) Baffin Island on June 1, 2019, June 18, 2019 Sentinel images and June 30 Landsat image. Purple dots indicate the snowline.

During June 2019 on Baffin island Pangnirtung featured four days with record temperatures for that date June 5 (15.1), June 11 (13.5) and June 12 (13.6), and June 19 (14.4). There were 14 days with a maximum temperature above 10 C. On Fork Beard Glacier and Nerutusoq Glacier this drove a snowline rise from 800 m on June 1 to 1100 m by June 18 and 1150 m on June 30. A rate of over 10 m/day for the month.

Eagle Island Ice Cap, Antarctica in Landsat images from Feb. 4, 2020 and Feb. 13, 2020. Point E indicates an are area of snow/firn that is saturated with

An all-time temperature record for Antarctica in February 2020, a high-pressure ridge and a blocking high in the Drake Passage caused anticyclonic circulation bringing warm moist air from the Pacific Ocean to the Antarctic Peninsula Xu et al (2021). This led to vertical air flows in a foehn warming event dominated by sensible heat and radiation made generating abrupt warming Xu et al (2021). The visible impact of this heat event were the rapid rapid formation of melt ponds on Eagle Island Ice Cap I reported to NASA EO. On Eagle Island Ice Cap melt averaged 22 mm/day from Feb. 6-11 based on MAR climate model output forced by the Global Forecast System (GFS) generated by Xavier Fettweis. Rapid melting generating significant snowline rise on Coley Galcier, James Ross Island as well (Pelto, 2020).

Nanpa La (NPL) and Nup La (NL) in October 13, 2020 and January 17, 2021 Landsat imagery indicating the snow line rise that has persisted into mid- winter. Snow line indicated by yellow dots.

When record warmth spread over the Mount Everest region in January 2021, the snow lines near Mount Everest rose durng the October-December 2020 period, and remained at nearly 6,000 meters, including the key glacier passes from Nepal into China being snow free into late January. The National Geographic Perpetual Planet Expedition weather team, led by L. Baker Perry and Tom Matthew, had installed weathers stations at high elevations on Mount Everest in 2019 (Matthews et al 2020). These stations provided field observation of how warm it was during this period, which explained the snow free glaciers in winter. Temperature observations and reconstructions of daily weather conditions, dating back to 1950, indicated that the region had experienced the five warmest winter days since 1950 during a short period in January 2021. Prajjwal Panday examined the decline of snow cover area and rise of sthe snowline on glaciers from Oct. 2020 -January 2021 finding a 15% depleation and 200 m rise respectively. Even in the highest mountain range in the world, we are seeing melt conditions during the winter. This study was first published by NASA EO within a month of the event, and then in the journal Remote Sensing.

Easton Glacier has limited snowpack with two months left in the melt season in 2021. Dots indicate the firn line.

The next warm weather event was the Pacific Northwest record heat in late June 2021, setting all-time records across the region. Thompson et al (2022). comparison of daily summer maximum temperaturesthat were 3.6 SDs from the mean.. This heat wave quickly melted away much of the winter snowpack on many glaciers. The heat wave and ensuing warmth stripped the snowcover from glaciers right to the summit on the highest mountains from Mount Shasta, California to Mount Baker, Washington by mid- August exposing the dirtier ice that lies underneath the snow and melts more rapidly than snow under the same weather conditions, to the summit of these mountains. The led to increased discharge in glacier fed streams, while non-glacier fed streams in the region had significant declines in discharge. For the Nooksack River heat waves generate a 24% increase in discharge in the glaciated North Fork and a 20% decline in the unglaciated South Fork (Pelto et al 2022). For water temperature the mean increase was 0.7 °C (±0.4 °C) in the North Fork and 2.1 °C (±1.2 °C) in the South Fork (Pelto et al 2022). The resulting volume loss during the summer season has been the highest we have observed in our 38 years of monitoring North Cascade glaciers. We observed stunted alpine plant growth, experienced days of smoky air limiting visibility and had to navigate and measure more open crevasses than usual.

Whitney Glacier on Mount Shasta in 2021 Sentinel Images.

Jackson and Blackfoot Glacier in early September Sentinel 2 false color images. Point A indicates exposed ice showing annual layers. Point B indicates exposed firn that had been retained through previous summers. The gray color of the firn indicates how dirty it is and that its albedo would enhance melting.

Mount Shasta in California fared even worse, losing all snow cover on its glaciers by September 6. The largest glacier on the mountain and in California, Whitney Glacier, began to separate. In all, the glaciers there had lost 50 percent of their area and volume this century, including ~10-15 percent this summer, and had fragmented from 6 into 17 glacier pieces (Patel, Washington Post, 2021).

The summer of 2022 in the Central Andes of Argentina and Chile glaciers experience a near total loss of snowpack in January due to early summer warmth, leading to dirty/dark glaciers. The darker surfaces of the glacier melt faster leading to more rapid area and volume loss. This includes fragmentation and rapid expansion of bedrock areas amidst the glacier. The snow free conditions lasted until the end of March, extending the impact from the January observations emphasizing that this was a regional issue this summer with snowpack lost from Bajo del Plomo Glacier, Cortaderal Glacier, Palomo Glacier, Volcan Overo Glaciers, Volcan San Jose Glaciers , Cobre Glacier and Olivares Beta and Gamma Glaciers across the Central Andes of Chile and Argentina.

Volcan San Jose glaciers in Feb. 17, 2022 Sentinel image. This highlights just how dirty the ice surface is and how limited the retained snowcover is.

Cobre Glacier, Argentina in false color Sentinel 2 images from Jnauary 13, 2022 and March 16, 2022. Note the expansion of bedrock area amidst the glacier at Point A, glacier fragmenting at Point B and Point C.

Volcan Overo in Sentinel image continues to fragment with no retained snowcover this summer, and bedrock expansion at Point A.

Sentinel images the loss of all snowcover on Sollipulli Glacier that continued from January until at least March 13 2022. Note the annual layers preserved in the glacier ice now exposed at the surface.

Langjokulen (La), Kvitisen (Kv), Bergfonna (Be) and Blaisen (Bl) ice caps on Edgeøya in Sentinel image from 8-20-2022 illustrating the lack of snowcover, limited firn areas and numerous annual layers. This pattern of annual layers due to glaciers being stripped of snow cover is becoming increasingly frequent. Note Andes last winter and Pacific Northwest summer 2021.

During the summer of 2022 Svalbard experienced an extended heat wave in August that led to loss of snowpack on a number of ice caps on Edgeoya.

Rapid snowcover loss on Rhone Glacier early in summer of 2022 in Sentinel images

The European Alps were hard hit in the summer of 2022 experiencing their most negative balances observed during the 70 years of observations.

In the summer of 2023 central Andean glaciers lost snowcover during the February heat waves.

Volcan Overo, Argentina with expanding lakes, blue arrows and fragmenting at yellow arrows.

Sollipulli Glacier lost snowcover in February 2023

The bottom line is that glaciers are simply not compatible with recurring heat waves and the intensity and frequency of these is increasing. This is true from Arctic Canada to the Himalayas from the Andes to Antarctica. This year, for the 34th consecutive year, Alpine glacier volume in the world will decline; their business model is not sustainable with our climate.

A 50-year Project on Columbia Glacier Annual Monitoring 1984-2022, 39 Years In

On April 18, 2022April 20, 2024 By mspeltoIn glacier climate change, Glacier Observations

1984-Landsat 5 is launched. The North Cascade Glacier Climate Project was initiated on Earth Day in 1984 with a goal of observing the impact of climate change on glaciers across this mountain range for 50 years. This was in response to a call to action by the National Academy of Sciences to have a project that monitored glaciers across an entire mountain range in the United States, and from climate scientist Stephen Schneider who challenged glaciologists at an IGS meeting in 1983 to begin the monitoring now, in order to identify the full scope of change. 50-Year Project of Glacier-article in National Geopraphic work

1985- 150,000 year climate record from Antarctic Ice Core . Snow covers the terminus of the glacier at the start of August note lateral moraines it is pressed up against.

1986-Glaciers and Ice Sheets and Sea Level: Effect of CO2 induced Climate Change-Conference Proceedings published. Thinning in 1985 and 1986 is exposing the lateral moraines, which are still ice cored.

1987-Montreal Protocol signed. Last year of positive global glacier mass balance. Columbia Glacier terminus fully exposed in early August revealing new large rocks at terminus

1988-IPCC formed. The terminus remains strongly convex, with much better snowcover. The slope is impressive note the skier for scale.

1989-Mean Global CO2 levels exceed 350 ppm. Note the annual layers both paralell to the terminus and in upper right avalanche fan annual layers that are diagonal to the terminus.

1990-First IPCC Assessmenent report , Clean Air Act amended to address Ozone Depletion and Acid Rain. Heavier accumulation nearly barely the lateral moraines at the terminus, indicative of a strong avalanche season.

1991-Mount Pinatubo erupts ejecting 15 million tons of SO2 into stratosphere impacting climate. No bare ice exposed in early August for the first time since we began monitoring the glacier. A strong positive mass balane. Widespread snow in the forest below the glacier.

1992- UN Framework on Climate Change signed by 154 nations. ~50% of the glacier bare ice in early August with 90% exposed by the end of summer, resulting in large mass loss.

1993-Melt ponds observations in Landsat images on Wilkins Ice Shelf leading to breakup event published. Lower half of Columbia Glacier exposed by early August.

1994-Velocity data acquired/published for Pine Island and Thwaites Glacier. Third consecutive year of large mass balance losses, lateral moraine increasingly prominent beyond retreating terminus.

1995- Second IPCC report- Another year of negative mass balance on Columbia Glacier leading to thinning from the top to the terminus of the glacier.

1996-CO2 levels exceed 360 ppm. Columbia Glacier has better avalanching than in the last four years, but still loses mass.

1997-First Prius Produced-Kyoto Protocol adopted. Good accumulaiton is back leaving most of the glacier covered in snowpack right through August.

1998-Super El Nino-First year with a +0.50 or greater Global Land-Ocean Temperature anomaly. A warm summer strips the glacier of 90% of its snowcover and much of the retained 1997 firn is lost too.

1999-World Record Snowfall at Mount Baker (28.96 m-1140 inches)- where we measure glacier mass balance. First Year Arctic Sea Ice minimum is below 6 million km2. We crossed part of Blanca Lake on the ice enroute to the glacier buried in deep snow with avalanches reaching the lake shore.

2000-Jakobshavn Isbrae, Greenland speeds up. Another year of good snowcover, though not as deep as in 1999.

2001-Third IPCC Assessment Report.

2002-LarsenB Ice Shelf Breakup. Good snowpack with some very strong avalanches including from the east wall that spread out onto the terminus.

2003-Deadly European Heat Wave. This was the first of several very negative mass balance years.

2004-Sea Level Rise 1993-2004 averages 3.5 mm/year. In Northern Atlantic there are 28 tropical storms. Only snow retained is in the large avalanche fans.

2005-Hurricane Katrina strikes New Orleans a $240 billion disaster. Globally hottest year yet. Most negative balance of our monitoring program, with the glacier losing 98% of its snowcover.

2006-First year exceeding nine million acres burned in US by wildfires. Impact of continued mass losses is a thinner glacier, with a reduced slope at the terminus.

2007-Fourth IPCC report-Arctic Sea Ice falls below 4 million km2 for first time. The west side avalanche fans, on left now only areas of persistent accumulation, hence their slope expanding across glacier.

2008-Wilkins Ice Shelf Collapse. Good snowpack with heavy avalanching onto glacier.

2009-37% Increase in US Wind Power Capacity. Glacier retreat since 1984 exceeds 100 m. Field work occurred during a record heat wave. This leads to an increased focus on heat wave impacts on the glaciers.

2010-Hottest year of record globally. The terminus slope continues to deflate during another year of negative balance.

2011-Global Wind Power capacity exceeds 200 GW. Deep snowpack remained through the summer leading to a signficant mass gain.

2012-Arctic Sea Minimum record at 3.39 million km2. Record loss from Greenland Ice Sheet. Snowpack again persisted through early August, leading to a small positive balance.

2013-Globally 45 Billion dollar weather disasters including 18 flooding events. Extensive summer melt led to snowpack loss and firn exposure from 2011 and 2012.

2014- Global Solar and Wind Power Capacity exceeds 500 GW. Marine Heatwave the Blob in Pacific Ocean. The summer of 2014 was the warmest we had experienced, which led to rapid snowpack removal in late summer.

2015-Paris Agreement-Over 10 million acres burned in US by wildfires. The winter was poor and the summer hot leading to no retained snowpack even in avalanche fans and the formation of a new lake at the terminus.

2016-Solar and wind energy economcially competitive. Hottest year on record. High ablation rates and summer forest fire smoke were the story of another poor year, new lake can be seen.

2017-Global Electric Car sales exeed 1.5 million units. Coral Reef Bleaching event impacts 2/3 of Great Barrier Reef. New lake continues to expand as glacier thins and retreats.

2018- Solar and Wind Energy installed capacity both exceed 500 GW. Retreat since 1984 exceeds 200 m. No snowpack retention except in avalanche fans.

2019-Global Electric car sales exceed 2.2 million units. Only 14% of the glacier retained snowpack by summer’s end.

2020- Thirty tropical storms in North Atlantic. The lake expanded substantially with a concave stagnant terminus exposed on its margin.

2021- Over 40 Billion dollar weather disasters in last two years in US. A climax avalanche event in February led to deep snowpack on the glacier. An early season heat wave melted off all snow except in the large avalanche fans.

2022- We will be back in the field for year 39 looking at snowpack depth, melt rate and extent across the glacier.

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.

Whitney Glacier , Mount Shasta Losing all of its Snowcover and Separating in 2021

On August 29, 2021April 22, 2024 By mspeltoIn glacier climate change2 Comments

Sentinel 2 False and True Color images from 8-25-2021. Yellow arrows indicate where glacier is separating and purple arrows the small remanent of 2021 snowpack remaining. This remanent will not last to the end of the melt season.

The summer of 2021 is proving to be catastrophic for Whitney Glacier on Mount Shasta, California in terms of volume loss, ~15-20% this year leading to long term impacts, adding to the 50% area reduction and 1000 m retreat since 2005. The glacier will lose 100% of its 2021 snowpack and is in the process of separating into two glaciers. Here we review the glaciers behavior in recent decades and examine using Sentinel Imagery the impacts in summer of 2021.Mount Shasta is a stratovolcano home to the largest glaciers in California, Whitney Glacier on the north side is the longest. In 1981 USGS (Driedger and Kennard, 1986) mapped the area and volume of several of the glaciers, in a landmark study of glacier volume on Cascade volcanoes. Whitney Glacier had an area of 1.3 km², a maximum depth of 38 m, and a volume of 25 million m ³. The majority of the glacier was in the 20-35 m thick range. The glacier was noted as having a length of 3.0 km ending on the USGS map at 9900 feet.

Digital Globe image indicating a area of retreat from 2005-2012 and the limited crevassing near 2012 terminus.

Tulaczyk and Howat (2008) noted that Whitney Glacier did advance during the 2000-2005 period, following a retreat in the 1980’s and 1990’s. The most recent advance was limited to the 1999-2005 period due to heavy snowfall from 1998-2002, ended with the glacier 850 m in advance of its 1951 position. There was a period of advance for many Cascade volcanoes glaciers between 1950 and 1980, followed by retreat after. On Mount Baker, Washington all of the glaciers advanced during the 1944-1979 period by an average of 480 m (Pelto and Hedlund, 2001). By 2010 Pelto and Brown (2012) observed all were retreating with an average retreat of 370 m. In 2012 the glacier is thin in its lower reaches with no crevassing. By 2014 the terminus of the glacier had retreated 700 m from 2005 and was 2.6 km in length and terminated at 10200 feet, 300 feet higher than a decade before or in the 1981 map.

Sentinel 2 True Color images from 6-16-2021, 6-28-2021 and 7-18-2021 illustrating the progressive snowcover loss on the glacier. Point A and D are on the upper Glacier, Point B is where the upper and lower glacier have joined and Point C is near the top of the lower glacier.

The summer of 2021 followed a 15 year period of overall significant mass loss and retreat on Whitney Glacier that led to a thinner glacier with a reduced velocity and consequently fewer crevasses. The stage was set with 60-75% of normal snowpack in early April 2021 at the stations in the region in the 6000-7600′ range, dropping to 20-25% of normal by early May (CDEC, 2021). This was followed by an exceptionally warm early summer, that helped strip the snowpack away early. By June 16, the snowline on Whitney Glacier had risen to 10,800 feet, near Point C, while the upper glacier extending from Point A and D to Point C was nearly all snowcovered. By June 28 the snowline had risen to 11,200 feet on the lower glacier and the upper glacier snowline was near 12,500 feet, with the west facing upper section (Point A) above 13000 feet nearly all bare. By July 18 there is a small area of snowcover near Point C on the lower glacier and Point D on the upper glacier. Most of the glacier is bare of snowcover. This underscores the particularly detrimental impact of early season heat waves that strip away winter snowpack and exposes the dirtier glacier ice and firn. The ice and firn melt ~30% faster than the snowcover for the same weather conditions. Our measurements on Mount Baker during heat waves over the last three decades indicate typical ice melt of 7-9 cm of melt per day. The average temperature over the last 70 days since much of the glacier was bare ice has been 16.8 C at Snow Bowl station at 7617 feet. Given area summer lapse rates this equates to a temperatures of ~12-13 C at the mean glacier elevation. The temperature at this station reached 29 C on June 27, 28 C on June 28 and exceeded 25 C from June 25-June 30. The rapid melt rate led to a number of areas of slushy, swampy glacier surface conditions even high on the glacier (Mount Shasta Avalanche Center ). Using the degree day formula for melt derive on Mount Baker during warm summer conditions (Pelto, 2015 and 2018) of .0053m w.e.C^-1D^-1, yields a cumulative melt of 4.8 m w.e., equivalent to over 5 m of ice thickness.

This given mean ice thickness in the 25-30 m range indicates that this summer ~15-20% of the glacier ice volume will be lost on Whitney Glacier. The glacier is now 2300 m long and has an area of 0.6 km ², which is less than 50% of its area just 16 years ago. This is leading to separation of the lower and upper glacier at the yellow arrows. There is certainly still stagnant ice in this zone, but there is no longer a dynamic connection between the upper and lower Whitney Glacier.

Topographic map of Mt. Shasta.indicating the top of Whitney Glacier near the summit of Shasta and the ~1981 and 2005 terminus position.

Benito Glacier, Chile 2021 Calving Event Drives Further Retreat

On April 13, 2021April 23, 2024 By mspeltoIn chile glacier retreat, climate change glacier retreat, glacier climate change

Benito Glacier in 2000 and 2021 Landsat images. Locations 1-6 are current or former distributary terminus locations. Red arrow is the 2000 terminus location and yellow arrow the 2021 terminus location. A small cloud is obscuring an iceberg near terminus. Purple dots are the snowline.

Benito Glacier is a temperate outlet glacier on the west side of the North Patagonian Icefield terminating in an expanding lake. The glacier is south of San Quintin Glacier and north of Acodado Glacier. Loriaux and Casassa (2013) examined the expansion of lakes of the Northern Patagonia Ice Cap. From 1945 to 2011 lake area expanded 65%, 66 square kilometers. Ryan et al (2018) identified thinning of 2.8 m/year in the ablation zone from 2000-2013, and that thinning of over 120 m extended from the terminus to ~750 m from 1973-2017. Mouginot and Rignot (2015) indicate that the velocity of Benito Glacier is between 200-500 m per year along the center line below the snowline. Glasser et al (2016) note the glacier has limited debris cover and that the average transient snowline in 2013-2016 is at 1000 m, substantially above the ~900 m average from earlier.

Benito Glacier in 1987 main terminus was on an outwash plain. The glacier has five distributary termini (1,2,34,5,6) two of which had open proglacial lakes in 1987. At Point 3 the glacier flows around a nunatak and reconnects. In 2000 a 1 km long proglacial has formed at the main terminus. Distributary termini 1,2 and 4 all have proglacial lakes. The snowline in 1987 and 2000 is 800-825 m. By 2015 there are five ending in lakes, with Lake 6 having retreated out of a lake basin. A lake has formed at the new distributary terminus at Lake 3. The two tributaries to the north indicated with arrows each retreat approximately 1 km from 1987 to 2015 and in both cases are no longer calving termini. The main glacier terminus has retreated into a proglacial lake, with a retreat of 2 km from 1987 to 2015. The lowest 1.5 km has a low slope and peripheral lakes suggesting the lake will expand substantially as Benito Glacier retreat continues. The transient snowline in 2015 is at 900 m. In 2021 a significant iceberg 0.4 km² has calved off the terminus. The terminus has retreated 2900 m from 1987-2021 with the lake area expanding to 2.8 km². The lower 1.5 km of the glacier remains low sloped suggesting significant lake expansion is ongoing. The glacier no longer reaches the former proglacial lake 2 or 6. Proglacial lake 1 has drained. Proglacial lake 2,3, and 4 continue to expand. The snowline on Feb. 6 2021 is at 875-900 m, rising to 925-950 m by March 16, 2021.

March 17, 2021 Landsat image indicating iceberg located off front of Benito Glacier

Benito Glacier comparison in Landsat images from 1987 and 2015 indicating the terminus position in 1987 red arrows, yellow arrows the 2015 terminus positions. Locations 1-6 are current or former distributary terminus locations. purple arrows where glacier thinning is expanding bedrock areas. The snowline is indicated by purple dots

Leningradskiy Ice Cap Snowcover Vanishes in 2020 More Thinning, Svernaya Zemlya

On September 14, 2020April 23, 2024 By mspeltoIn glacier climate change, russia glacier retreat

Leningradskiy Ice Cap north to south strip in 2000 and 2020 Landsat images illustrating thinning leading to separation of parts of the ice cap at Point 1 and 4 and expansion of bedrock leading to merging bedrock regions at Point 1 and 2. R=snow/firnpack saturated with meltwater and consequent potential refreezing. S=superimposed ice development from surface refreezing.

Leningradskiy Ice Cap is oriented east to west across Bolshevik Island in the Svernaya Zemlya Archipelago of the Russian Arctic. Annual snowfall on the ice caps is limited ~0.4-0.5 m (Sharov and Tyukevina, 2010). During the brief summer melt season from June-late August, much of the melt is refrozen within the snow/firnpack or as superimposed ice (Bassford et al 2006). The low snowpack makes the glaciers vulnerable to warm summer conditions. The summer of 2020 has been remarkably warm in the Russian High Arctic leading to high melt rates and surface mass balance loss as shown by Xavier Fettweise MAR model. Here we examine Landsat images from 2000 to 2020 to identify a pattern of thinning on the northern margin of the ice cap.

In 2000 the glacier has a well established glacier runoff stream at yellow arrow. Point 1 is a nunatak amidst a peripheral segment of the ice cap. Point 2 is an area of bedrock separated by a narrow section of ice cap from adjacent bedrock. Point 3 and 4 are locations where the ice cap is thick enough to spillover in to an adjacent basin. There is little visible snowpack on the ice cap, but a significant area of azure blue indicates snow/firnpack (R) that is saturated with meltwater, some of which will refreeze. There are zones of superimposed ice development(S) where meltwater is refreezing on top of the cold surface ice. In 2018 there an area of unsaturated snowpack, white area, and saturated snow/firnpack (R) azure blue and areas of superimposed ice development (S).

On August 3, 2020 the ice cap has lost its snowcover with limited areas of firn, limiting the ability of meltwater to refreeze except on the surface as superimposed ice (S). The lack of snow/firnpack at the surface will lead to a more negative balance as meltwater is not retained. At Point 1 this peripheral glacier area has been cutoff from the main ice cap as thinning has exposed more of the encircling ridge. At Point 2 bedrock areas have expanded and merged together. At Point 3 there is some spillover still but thinning has led to a reduction and consequent retreat and thinning of this terminus. At Point 4 the ice cap no longer spillovers into the adjacent basin due to thinning. Each location indicates significant thinning that is hard to recover given the slow flow and limited accumulation on these glaciers. On Aug. 22 2020 the surface of the ice cap is frozen, leading to a whiter surface.

The lack of retained snowcover in 2020 was also seen at Hochstetter Ice Cap in Franz Josef Land. In both cases the high summer temperatures led to more meltwater, and the lack of snowpack to retain leads to more escaping the system. Bassford et al (2006) describe this process “Intense surface melting in the accumulation zone during warm summers prevents the buildup of a thick firn layer by rapid transformation of firn to ice through refreezing and by removing
mass through runoff.”

Leningradskiy Ice Cap north to south strip in 2018 and 2020 Landsat images illustrating changing distribution of melting (R) and superimposed ice development (S)

North Cascade Glacier Climate Project Observations 2020, 37th Field Season

On August 31, 2020April 24, 2024 By mspeltoIn glacier climate change, Glacier Observations, North Cascade Glaciers

The North Cascade Glacier Climate Project 2020 field season was our 37th consecutive year of glacier observations. The field team consisted of Cal Waichler, Mariama Dryak, Jill Pelto and Mauri Pelto. Each team member has studied glaciers on more than one continent and is passionate about science communication, using either art, videography or writing.

Mauri Pelto, Jill Pelto, Cal Waichler and Mariama Dryak from left to right on Easton Glacier the 2020 field team (Jill Pelto Photograph).

At Columbia Glacier the field team was joined by Michelle Tanz a Wlderness Stewardship Fellow for the National Forest Service. The initial observation was that the 2 km bushwhack around Blanca Lake has gotten much brushier as the alpine meadow becomes more sub-alpine. Columbia Glacier is a low elevation avalanche fed glacier that developed a new lake at its terminus a decade ago that continues to expand. The east side of the glacier has been thinning much faster than the west side altering the very shape of the glacier. Observed snowpack in 2020 was below average except for on the slopes of the main west side avalanche fans. The upper basin at 1550-1650 m averaged 2.2 m of snowpack at the 70 probing locations, which is 70% of normal. This snowpack will not survive the melt season, only snowpack in the main avalanche fans will remain. Terminus retreat has been 217 m since our first observation in 1984.

Lower Curtis Glacier is fed by avalanches from the slopes of Mt. Shuskan. We were joined in the field by Tom Hammond for the 17th consecutive year and artist Claire Giordano. There was a similar pattern to Columbia Glacier in that snowpack across most of the glacier was below average, while the primary avalanche fan on the east side had above average snowpack. The avalanche fans on the central headwall of the glacier fed from the Upper Curtis Glacier continue to thin rapdily, as avalanching has declined. The terminus slope which had been a daunting 42 degrees in 2015 is now 34 degrees. For the sixteenth consecutive year we had at least one artist in the field, below are field sketches from Cal Waichler and Jill Pelto and a painting from Claire Giordano. We will be combining the science findings and art in forthcoming articles on Lower Curtis and Easton Glacier.

Claire Giordano working on painting of Lower Curits Glacier and Mt. Shusksan (Mariama Dryak Photograph).

Jill Pelto completes sketch, while sitting on ice chunk, of Easton Glacier icefall (Mariama Dryak Photograph).

Cal Waichler annotated story board style sketches both capture and explain the scene at Columbia Glacier (Mariama Dryak Photograph).

Rainbow Glacier has a terminus that is largely buried by avalanches, but is now is close to detaching from the main valley glacier. Snowpack at 1700 m averaged 2.4 m which is 75% of average. The saddle with Mazama glacier at 2000-2100 m averaged 3.9 m, which is 85% of normal. Subglacial bedrock knobs continue to become more prominent in expanding crevassing above and slope below the slope change, as the glacier thins.

Sholes Glacier had the highest percentage of surface blue ice of the glaciers observed. Snowpack had been reduced from at a rate of 8 cm/day during the first week of August, a relatively warm period. A snow cave at the terminus could be entered from a terminus crevasse that was 50 m long, 10 m wide and 2-5 m high. This is indicative of a relatively stagnant rapidly retreating terminus. From 2014-2020 the glacier has retreated 80 m, which is equivalent to the retreat from 1990-2014. Glacier runoff continues to be monitored just below the glacier by the Nooksack Tribe, while we provide continued rating curve development. Runoff during early August was averaging 0.25 m³/sec.

On Easton Glacier the terminus slope was the gentlest we had seen in our 31 years of consecutive observations. The terminus has retreated 430 m in this period. The significant thinning in the last few years had both reduced crevassing in the lowest icefall, but had reduced crevasse depth. Jill Pelto has been observing the crevasses depth in all the open crevasses in this icefall over the last decade. The biggest change has been from 2018-2020 with average depth being reduced by 40%. Snowpack on the bench at 2000 m averaged 2.4 m at the 45 observation sites, which is 75% of normal. The snowpack remained below normal at 2200 m, before a sharp increase to above normal snowpack averageing 5.1 m in 14 crevasse observations at ~2500 m. At this same elevation retained snowpack, now firn from previous years averaged 2.25 m. Based on the storm stratigraphy one significant difference was the result of an atmospheric river precipitation event of 12+ cm of precipitation from 1/31-2/2, that led to a snow depth and snow water equivalent decline at the Middle Fork Nooksack Snotel at 1550 m, while above 2300 m this all fell as snow. The freezing levels were above 2000 m for much of the event. The better high elevation snowpack will help Easton Glacier’s mass balance in 2020.

Easton Camp from adjacent to 1990 terminus position (Jill Pelto Photograph).

Crevasse stratigraphy at 2500 m on Easton Glacier indicates an average of 5.1 m of 2020 snowpack in crevasses and 2.25 m for previous annual layers from the 2016-2019 period (Mauri Pelto and Jill Pelto Photographs)

NORTH CASCADE GLACIER CLIMATE PROJECT 2020-37th Annual Field Program

On July 28, 2020April 24, 2024 By mspeltoIn glacier climate change, North Cascade Glaciers2 Comments

Field season images from 2019 indicating crevasse stratigraphy, annotated by Clara Deck.

Director: Mauri S. Pelto, mspelto@nichols.edu-Nichols College

Field Artist & Scientist: Jill Pelto, pelto.jill@gmail.com

Who we are? NCGCP was founded in 1983 to identify the response of North Cascade glaciers to regional climate change, particularly changes in mass balance, glacier runoff and terminus behavior. NCGCP is a field project that has a broader interdisciplinary scope and examines more glaciers than any other program in North America. It does so cost effectively relying on no permanent camps, helicopter support or salaries for the director. 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 and glacier runoff monitoring. This program monitors two of the World Glacier Monitoring Service’s reference glaciers. There are ~45 such glaciers in the world with 30 years of continuous measurements. We complete mass balance and terminus observations on Columbia, Daniels, Easton, Ice Worm, Lower Curtis, Lynch, Rainbow and Sholes Glacier with runoff measurements below Sholes and Ice Worm.

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.

Field Team 2020:

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, as earlier in July was illustrated on the cover of TIME. She completed both her B.A. degrees in Studio Art and Earth and Climate Sciences 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 12th 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 on the Science Advisory Board for NASA’s Earth Observatory. His primary job is Dean of Academic Affairs at Nichols College, where he has been a professor since 1989.

Cal Waichler is an environmental science major at Colby College in Maine and is from Winthrop, WA. She looks to bridge the gap between science and the public by creating impactful, accurate climate art and storytelling. This summer’s research goal is to generate building blocks to contextualize her work within two fields: glacier science and climate communication.

Mariama Dryak (she/her) is an earth scientist, science communicator/writer and an advocate for action on creating solutions to the global climate crisis. Mariama is the creator and editor of an environmental advocacy blog Let’s Do Something BIG. and the ‘we persist.’ podcast, which shares the stories of underrepresented people in the earth, ocean and environmental sciences. Mariama received her Master’s from the University of Maine in 2019 in Earth and Climate Science, during which she drew connections between inferred ocean conditions and glacier change along the Antarctic Peninsula. Mariama can most often be found chatting science, going on adventures or getting muddy whilst doing something outdoors.

**Columbia Glacier terminus with the 2018 field team.**

Field Partners 2020

Victoria Jarvis and Michelle Tanz are Wilderness Stewardship Fellows who will be gathering information about the Henry M Jackson Wilderness including the glacier. They are looking to understand the Columbia Glacier and our research within the scope of the 5 qualities of wilderness character (untrammeled, undeveloped, natural, solitude and primitive rec, other). They will then be able to incorporate our long-term monitoring efforts into their wilderness character narrative– a synthesized agency document providing insight about the wilderness.

Alia Khan, Western Washington University Cryosphere Studies and Aquatic Biochemistry Lab:

The research team including grad students Molly Peek 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.

Tom Hammond, North Cascade Conservation Council,Will be joining us for the 17^th year leveraging his experience with our for understanding the ongoing impact of climate change and our stewardship on the region.

Nooksack Indian Tribe, for the 9^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.