Glacier

Glacier Crevasses: A Review

Posted by William Colgan on February 29, 2016
New Research / No Comments

We have a new review paper on glacier crevasses in the current issue of Reviews of Geophysics1. We survey sixty years of crevasse studies, from field observations to numerical modeling to remote sensing of crevasses, and also provide a synthesis of ten distinct mechanisms via which crevasses influence glacier mass balance.

Two years ago, our team embarked on what was supposed to be a brief review of crevasse science to help interpret maps of Greenland crevasse extent that we are generating from laser altimetry data as part of a NASA project entitled “Assessing Greenland Crevasse Extent and Characteristics Using Historical ICESat and Airborne Laser Altimetry Data”. The final review ended up containing 250 references and being 43 typeset pages in length. Evidently we found the crevasse life cycle contained more nuances than we had initially assumed! Here are some of the highlights that have shifted our paradigm:

Field observations – Although crevasses are conventionally conceptualized to initiate at the surface and propagate downwards, we were surprised to find compelling evidence that at least some crevasses initiate at several metres depth, before propagating upwards to appear at the glacier surface. For example, observations that new crevasses can intersect relict crevasses at angles as low as 5 ° indicates that the stresses governing fracture are below the depth of relict crevasses (as relict crevasses do not serve as stress foci). This has implications for interpreting “buried” crevasses as relict or active.

Crevasse_Field_Sample

Figure 1 – Measured principal strain rates and crevasse locations observed circa 1995 at Worthington Glacier, USA2. The cross-cutting of relict crevasses by active crevasses indicates relative crevasse chronologies can exist at a single point on a glacier.

Numerical modeling – While crevasses have conventionally been assumed to form perpendicular to principal extending stresses on glaciers, we were intrigued to find strong model evidence that non-trivial crevasse curvature and rotation can result when there is substantial shearing (Mode III fracture) acting in addition to the more the common opening (Mode I fracture). The role of such mixed-mode fracture in shaping crevasse geometry has implications for interpreting curved / rotated crevasses as either deformed following opening or in equilibrium with local shear.

Crevasse_Modes

Figure 2 – Schematic illustrating the three modes of fracture: Mode I (opening), Mode II (sliding), and Mode III (tearing).

Remote Sensing – Remote sensing technologies for crevasse detection exhibited remarkable growth over the past 60 years. Real-time crevasse detection for traverse vehicles advanced from Cold War era rudimentary push-broom “dishpans”, which measured bulk electric current density of surrounding ice, to modern fully autonomous rovers capable of executing ground penetrating radar grids. In terms of satellite imagery, crevasses went from being manually delineated in the coarse resolution visible imagery that became available in the 1970s to now being automatically detected by feature tracking algorithms in higher resolution visible and synthetic aperture radar imagery.

CrevassePastPresent

Figure 3 – Left: Cold War era “dishpan” detection system that inferred crevasses from changes in bulk electric current density3. Right: An autonomous ground-penetrating radar unit (Yeti) being used to map near-surface buried crevasses at White Island, Antarctica. (Photo: Jim Lever)

Mass Balance Implications – While many studies have described individual mechanisms by which crevasses can influence glacier mass balance, we wanted to provide an overview of all the possible mechanisms, and we were fortunate enough to have a graphic artist help us do it in a single schematic. The mass balance implications of crevasses contain several counter-intuitive nuances. For example, crevasses can enhance basal sliding in the accumulation area and suppress basal sliding in the ablation area. Given their myriad mass balance implications, however, crevasses may serve as both indicators and agents of changing glacier form and flow.

Crevasse_Summary

Figure 4 – Schematic overview of the various processes through which crevassed surfaces influence glacier mass balance relative to non-crevassed surfaces: (1) increased solar energy collection and enhanced surface ablation, (2) increased turbulent heat fluxes and enhanced surface ablation, (3) decreased buried crevasse air temperatures and suppressed ice deformation, (4) increased bulk glacier porosity and enhanced ablation area water retention, (5) increased supraglacial lake drainage and suppressed accumulation area water retention, (6) increased supraglacial lake drainage and enhanced ice deformation, (7) attenuated transmission of hydrologic variability (relative to moulins) and suppressed basal sliding velocities, (8) increased cryo-hydrologic warming of ice temperatures and enhanced ice deformation, (9) increased water content / hydraulic weakening and enhanced ice deformation, and (10) iceberg calving.

1Colgan, W., H. Rajaram, W. Abdalati, C. McCutchan, R. Mottram, M. S. Moussavi and S. Grigsby. 2016. Glacier crevasses: Observations, models, and mass balance implications. Reviews of Geophysics. 54: doi:10.1002/
2015RG000504.

2Harper, J., N. Humphrey and W. Pfeffer. 1998. Crevasse patterns and the strain-rate tensor: A high-resolution comparison. Journal of Glaciology. 44: 68–76.

3Mellor, M. 1963. Oversnow Transport. Cold Regions Science and Engineering. Monograph III-A4. 104 pages.

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New Report: Applied Glaciology Primer

Posted by William Colgan on November 13, 2015
Applied Glaciology, Glaciers and Society / No Comments

The Geological Survey of Denmark and Greenland (GEUS) has been involved in several applied glaciology projects since the early 1980s, such as assessments for the hydropower plants now operating at Ilulissat and Nuuk, and glacial lake outburst flood assessments for Isortuarsuup and Qorlortossup in South Greenland. In a report entitled “Unique applied glaciology challenges of proglacial mining” in this year’s Report on Geological Survey Activities, we provide a brief overview of four unique glacier-related geotechnical challenges confronting industrial operations adjacent to a glacier. We discuss these four especially unique applied glaciology challenges in the context of a new generation of mining projects that seek to excavate through glaciers to reach sub-glacial ore, such as the active Kumtor Mine in Kyrgyzstan and the approved Isua Mine in Greenland. The four uniquely glacier-related geotechnical challenges we discuss are supraglacial runoff, subglacial water flow, ice movement and supraglacial access roads. We also highlight how climate change is poised to further exacerbate these geotechnical challenges, as increased meltwater production generally enhances both water flow and ice flow into proglacial sites. We hope this report can serve as a quick survey of recent applied glaciology activities for non-specialists.

ROSA_sites

Site overviews of the recently approved Isua project in Greenland (left) and the recently approved Kerr-Sulphurets-Mitchell and Brucejack projects in Canada (right).

*W. Colgan, H. Thomsen and M. Citterio. 2015. Unique applied glaciology challenges of proglacial mining. Geological Survey of Denmark and Greenland Bulletin. 33: 61–64.

*This report serves as the citation for the proglacial mining projects open-file located here.

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Kokanee Glacier Beer and the 1962 “Bomb Horizon”

Posted by William Colgan on August 28, 2015
Cold War Science, Glaciers and Society / No Comments

Dear Kokanee Beer,

I was delighted to hear that, in celebration of Kokanee’s founding in 1962, you’ve decided to sponsor some glaciology research in exchange for the recovery of five liters of glacier ice from 1962. It just so happens that 1962 is also an auspicious year for glaciologists. We glaciologists know 1962 as the “bomb horizon”, due to a worldwide peak in the atmospheric deposition rates of radionuclides derived from thermal weapons testing. Tsar Bomba, the largest thermal-nuclear weapon ever tested, with a yield of over 50 MT, had just been detonated the previous fall (30 October 1961). The USSR conducted about 40 thermal-nuclear weapons tests in 1962, and the US conducted closer to 100! After each test, the radionuclide fallout drifted around the atmosphere for a few weeks before raining down on the landscape, glaciers included.

Fortunately for us glaciologists, the glaciers proved to be really effective in retaining those radionuclides under subsequent snowfall. These days, we can just drill a deep hole in a glacier, lower down a gamma spectrometer, find the peak in radioactivity, and get a quick estimate of the 1962 depth. As you can see from the attached graph of radioactive 137Cs decay with depth, the present-day radioactivity of the 1962 “bomb horizon” is about equivalent to the background radioactivity found today at the glacier surface. So, 1962 melted glacier water is definitely not worse to drink than 2015 melted glacier water, I was just thinking that instead of calling your beer Deja Brew, maybe you should perhaps consider Thermonuclear Haze or even Cesium Peak to really give a fair nod to your 1962 glacier roots?

Yours truly,

William Colgan, Ph.D.

Thermo_Wiki2

Figure 1 – Annual count of world wide thermo-nuclear weapons tests between 1945 and 2013. By far, 1962 was the peak in number of weapons tested. (from Wikipedia)

Thermo_profile

Figure 2 – Profile of radioactive cesium (137Cs) with depth, as well as control profile from a  cadmium (109Cd) source located on the detector, recovered from the Devon Ice Cap in the Canadian Arctic in 2005. The arrow points to the apparent 1962 “bomb horizon”. We talk about using this independent dating technique for ice cores in Colgan and Sharp (2008).

Colgan, W. and M. Sharp. 2008. Combined oceanic and atmospheric influences on net accumulation on Devon Ice Cap, Nunavut, Canada. Journal of Glaciology. 54: 28-40.

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Artificial Glacier Surges at Kumtor Mine

Posted by William Colgan on July 27, 2015
Applied Glaciology, New Research / No Comments

Jamieson and colleagues published a very neat investigation of the applied glaciology challenges at Kumtor Mine, Kyrgyzstan, this week in the AGU Journal of Geophysical Research: Earth Surface (open access here). The recovery of subglacial gold deposits at Kumtor Mine has necessitated the excavation of an open ice pit into the Lysii and Davidov Glaciers. In addition to excavating glacier overburden, a major geotechnical challenge at Kumtor Mine has been managing the flow of both glaciers. In their study, Jamieson et al. (2015) use a comprehensive set of high resolution satellite images to document recent artificial surges induced in both these glaciers in response to mining activities. Photos released by Radio Free Europe in 2013 suggest that these artificial surges quite adversely impacted mining operations (Figure 1).

Kumtor_glacier_damage

Figure 1 – Infrastructure damage resulting from what is now a confirmed glacier advance at the Kumtor Mine in Kyrgyzstan (originally discussed in this earlier post)

The dumping of waste rock on both glaciers, in which waste rock piles reached up to 180 m thick, substantially increased the driving stress of the ice beneath. Given that ice deformation is related to driving stress to an exponent of three, and potentially higher exponents at higher driving stresses, this resulted in a significant increase in ice velocity. Jamieson et al. (2015) estimate that surface velocities of the Davidov Glacier increased from a few meters per year to several hundred meters per year within a decade. During this time, the Lysii and Davidov Glaciers advanced by 1.2 and 3.2 km, respectively, with Davidov Glacier terminus advance reaching 350 meters per year in c. 2012 (Figure “7”).

Jamieson1

This study is probably the most textbook-comprehensive documentation of a human-induced artificial glacier surge to date, and will provide a great resource for my students to debate the sometimes fine line between geotechnical misstep and natural hazard!

Reference

(Jamieson, S., M. Ewertowski and D. Evans. 2015. Rapid advance of two mountain glaciers in response to mine-related debris loading. Journal of Geophysical Research: Earth Surface. 120: doi:10.1002/2015JF003504.

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Hybrid Gravimetry and Altimetry Mass Balance

Posted by William Colgan on July 07, 2015
Communicating Science, New Research, Sea Level Rise / No Comments

We have a new study in this month’s Remote Sensing of Environment, which examines satellite-derived glacier mass balance in Greenland and the Canadian Arctic1. Satellites are generally used to assess glacier mass balance through changes in volume (via satellite altimetry) or changes in mass (via satellite gravimetry). While satellite altimetry observes volume changes at relatively high spatial resolution, it necessitates the forward modeling of firn processes to convert volume changes into mass changes. Conversely, the cryosphere-attributed mass changes observed by satellite gravimetry, while very accurate in absolute terms, have relatively low spatial resolution. In this study, we sought to combine the complementary strengths of both approaches. Using an iterative inversion process that was essentially sequential guess-and-check with a supercomputer, we refined gravimetry-derived observations of cryosphere-attributed mass changes to the relatively high spatial resolution of altimetry-derived volume changes. This gave us a 26 km spatial resolution mass balance field across Greenland and the Canadian Arctic that was simultaneously consistent with: (1) glacier and ice-sheet extent derived from optical imagery, (2) cryospheric-attributed mass trends derived from gravimetry, and (3) ice surface elevation changes derived from altimetry. We have made digital versions of this product available in the supplementary material associated with the publication.

Figure_1

Figure 1 – Observational data inputs to our inversion algorithm. A: Cryosphere-attributed mass changes observed by gravimetry. B: Land ice extent observed by optical imagery. C: Ice surface elevation changes observed by altimetry.

To make sure our inferred mass balance field was reasonable, we evaluated it against all in situ point mass balance observations we could find. Statistically, the validation was great, yielding an RMSE of 15 cm/a between the inversion product and in situ measurements. Practically, however, this apparent agreement largely stems from the fact that we could only find forty in situ point mass balance observations against which to compare. Evaluating our area-aggregated sector-scale mass balance estimates against all previously published sector-scale estimates provides a more meaningful validation. This suggests the magnitude and spatial distribution of inferred mass balance is reasonable, but highlights that the community needs more in situ point observations of mass balance, especially from peripheral glaciers and regions of high dynamic drawdown in Greenland. (For the glaciology hardcores I will note that “mass balance” is distinct from “surface mass balance”, in that the former measurement also includes the ice dynamic portion of mass change.)

Figure_11_corrected

Figure 2 – A comparison of similar sector scale mass balance estimates and associated uncertainties across Greenland and the Canadian Arctic. Dashed lines denote estimates that pertain to the Greenland ice sheet proper (i.e. exclusive of peripheral glaciers). Jacob et al. (2012) estimates pertain to Canada, while Sasgen et al. (2012) estimates pertain to Greenland.

This new inversion mass balance product, which we are calling “HIGA” (Hybrid glacier Inventory, Gravimetry and Altimetry), suggests that between 2003 to 2009 Greenland lost 292 ± 78 Gt/yr of ice and the Canadian Arctic lost  42 ± 11 Gt/yr of ice. While the majority of Greenland’s ice loss was associated with the ice sheet proper (212 ± 67 Gt/yr), peripheral glaciers and ice caps, which comprise < 5 % of Greenland’s ice-covered area, produced ~ 15 % of Greenland mass loss (38 ± 11 Gt/yr). A good reminder that ice loss from “Greenland” is not synonymous with ice loss from the “Greenland ice sheet”. Differencing our tri-constrained mass balance product from a simulated surface mass balance field allowed us to assess the ice dynamic component of mass balance (technically termed the “horizontal divergence of ice flux”). This residual ice dynamic field infers flux divergence (or submergent ice flow) in the ice sheet accumulation area and at tidewater margins, and flux convergence (or emergent ice flow) in land-terminating ablation areas. This is consistent with continuum mechanics theory, and really highlights the difference in ice dynamics between the ice sheet’s east and west margins.

Figure_13

Figure 3 – Spatially partitioning the glacier continuity equation in surface and ice dynamic components. A: Transient glacier and ice sheet mass balance. B: Simulated surface mass balance. C: Residual ice dynamic (or horizontal divergence of ice flux) term. The ∇Q color scale is reversed to maintain blue shading for mass gain and red shading for mass loss in all subplots. Color scales saturate at minimum and maximum values. Black contours denote zero.

As with some scientific publications, this one has a bit of a backstory. In this case, we submitted a preliminary version of the study to The Cryosphere in December 2013. After undergoing three rounds of review at The Cryosphere, the first one of which is archived in perpetuity here, it was rejected, primarily for insufficient treatment of the uncertainty associated with firn compaction. Coincidentally, on the same day I received The Cryosphere rejection letter, I received a letter from the European Space Agency (ESA) granting funding for a follow-up study. A mixed day on email indeed! After substantial retooling, including a discussion section dedicated to firn compaction and the most conservative error bounds conceivable, we were happy to see this GRACE-ICESat study funded by NASA and the Danish Council for Independent Research appear in Remote Sensing of Environment. The editors at both journals, however, were very helpful in moving us forward. Our ESA-funded GRACE-CryoSat product development is now ongoing, but a sneak peek is below.

ESA_partition

Figure 4 – Same as Figure 3, except using a 5 km resolution GRACE-CryoSat inversion product instead of a 26 km resolution GRACE-ICESat inversion product. Colorbars are different in shading, but identical in magnitude.

Reference

1W. Colgan, W. Abdalati, M. Citterio, B. Csatho, X. Fettweis, S. Luthcke, G. Moholdt, S. Simonsen, M. Stober. 2015. Hybrid glacier Inventory, Gravimetry and Altimetry (HIGA) mass balance product for Greenland and the Canadian Arctic. Remote Sensing of Environment. 168: 24-39.

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Glacier Crevasses: Searching for Curious Factoids

Posted by William Colgan on June 01, 2015
Glaciology History / 1 Comment

Along with some co-authors, with whom I am preparing a review paper about glacier crevasses, I am currently searching for a citation for the “deepest air-filled crevasse depth” measured to date. Although there seems to be some anecdotal assertions of 50 m deep crevasses in popular literature, presently, the deepest measured air-filled crevasse depth we have come across in the peer-reviewed literature is a third-hand account of a crevasse rescue in Palmer Land, Antarctica, in 1947, where crevasse depth is noted as “110 feet” (or 34 m). The rescue, one of many briefly recounted in Schuster and Rigsby (1954), reads:

Deepest_Crevasse_Report

One of many crevasse rescues recounted in Schuster and Rigsby (1954).

We presume that someone, somewhere, must have measured a deeper air-filled crevasse depth. I should note, we are aware that deeper crevasse depths have been inferred (rather than actually measured). For example, Hambrey (1976) suggests that the advection of crevasse traces c. 40 years down-glacier from their crevasse field of origin, where surface ablation averages c. 2 m/a, would infer that the fracture tips of crevasses reach c. 80 m depth within the crevasse field. Mottram and Benn (2009) recount the obvious challenge in accurately measuring the depth of an almost infinitely tapering fracture! For the purpose of our review paper, we are most interested in bona fide measurements, such as those made by either ranging devices or rappelling personnel, rather than someone just looking into the abyss and estimating “about X m deep”.

We are quite eager to see if anyone can point us in the direction of a deeper air-filled crevasse measurement. Naturally, we would also welcome (and duly attribute!) any other curious crevasse factoids or photographs that might be suitable for spicing up our meandering tour through the past seventy years of glacier crevasse literature. For example, we think we have identified the widest documented regularly spaced crevasse (air-gap width of 33 m!), which was observed in 1955 by Meier et al. (1957) at Blue Ice Valley, Greenland. We must admit, however, that we do most of our learning in the peer-reviewed literature, so we suspect that more adventurous souls (who might actually do some learning in crevasses!) may possess some alternate knowledge!

C3_Meier57_1_small

Thanks to some graphic assistance from Cheryl McCutchan (animediascience.com), we can merge strain rate and surface morphology maps in older studies, like this depiction of a 33 m wide crevasse at Blue Ice Valley, Northwest Greenland, from Meier et al. (1957).

Hambrey, M. 1976. Structure of the glacier Charles Rabots Bre, Norway. Geological Society of America Bulletin. 87: 1629-1637.

Meier, M., J. Conel, J. Hoerni, W. Melbourne, C. Pings and P. Walker. 1957. Preliminary Study of Crevasse Formation: Blue Ice Valley, Greenland, 1955. Snow, Ice and Permafrost Research Establishment. Report 38.

Mottram, R. and D. Benn. 2009. Testing crevasse-depth models: a field study at Breiðamerkurjokull, Iceland. Journal of Glaciology. 55: 746-752.

Schuster, R. and G. Rigsby. 1954. Preliminary Report on Crevasses. Snow, Ice and Permafrost Research Establishment. Special Report 11.

Twitter: @GlacierBytes

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Glacier Mining Photos & Videos (Open File)

Posted by William Colgan on February 03, 2015
Applied Glaciology, Glaciers and Society / No Comments

I have started this open file of selected glacier mining photos and videos with content mostly gleaned from Twitter. At present its coverage is limited to Kumtor Mine, Kyrgyzstan, but I am interested in content that illustrates the unique geotechnical challenges of working with glaciers from other proglacial mining projects too. So please contact me if you have some!

Photos

Open ice pit at Kumtor Mine, Kyrgyzstan in 2013 (via Ryskeldi Satke).

Open ice pit at Kumtor Mine, Kyrgyzstan in 2013 (via Ryskeldi Satke).

6 - активисты Саруу, июль 2013 посещ Кумтор

An excavator used for glacier mining at Kumtor Mine, Kyrgyzstan (via Ryskeldi Satke).

4 - активисты Саруу, июль 2013 посещ. Кумтор

A glacier cut face at Kumtor Mine, Kyrgyzstan (via Ryskeldi Satke).

 

Videos

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Proglacial Mining Projects (Open File)

Posted by William Colgan on January 08, 2015
Applied Glaciology, Glaciers and Society / No Comments

Proglacial mines, meaning mining operations adjacent to, or very close to, glaciers, face a variety of unique glaciological challenges not present in conventional mining operations: (1) Removing ice overburden to access a subglacial ore introduces both ice excavation and ice flow management challenges. (2) In addition to potential crevasse hazards, supraglacial vehicle access roads must use adaptive engineering to counteract ice movement (both horizontal and vertical) as well as differential surface ablation. (3) Tremendous glacier meltwater runoff, concentrated during the summer melt season, can be difficult to route across highly transient glacier surfaces in order to minimize site inflow/contact water. (4) The dust created by open pit operations or access roads can darken the surface of nearby glaciers, enhancing their solar absorption and surface melt rates, and ultimately expand the impact footprint of a mine. (5) The catastrophic drainage of supraglacial and/or ice-dammed lakes represent outburst flood hazards which can rapidly increase site inflow rates. (6) Subglacial hydrology can interact with the groundwater seepage in underground mining operations beneath glaciers. We touch on some of these glaciological hazards in the new textbook: “Snow and Ice-Related Hazards, Risks, and Disasters”. These geotechnical challenges make proglacial mining projects very unique. I started this “open file” inventory of proglacial mining projects (past, present and future) and their associated glaciological challenges as I pull together information for an applied glaciology review paper. Please alert me to any errors or oversights!

ProjectPrime
Minerals
LocationGlaciological ChallengesApparent
Status
Isua
[Fig. 1]
Fe 65.195 °N, 49.790 °W
(Greenland)
- ice removal / flow management
- glacier access roads
- meltwater runoff
- supraglacial lake outbursts
- darkening of nearby glaciers
Approved in 2013.
Kumtor
[Fig. 2]
Au41.862 °N, 78.196 °E
(Kyrgyzstan)
- ice removal / flow management
- glacier access roads
- meltwater runoff
- darkening of nearby glaciers
Active since 1997.
Kerr-Sulphurets-
Mitchell
[Fig. 3]
Au, Ag, Cu, Mo56.491 °N, 130.335 °W
(Canada)
- glacier access roads
- meltwater runoff
- darkening of nearby glaciers
Approved in 2014.
TutoN/A76.417 °N, 68.269°W
(Greenland)
- ice removal / flow management
- glacier access roads
- meltwater runoff
Historic project (1955 to 1959).
GranducCu56.247 °N, 130.089 °W
(Canada)
- ice removal / flow management
- meltwater runoff
- darkening of nearby glaciers
Historic project (1964 to 1983).
MalmbjergMo 71.964 °N, 24.289 °W
(Greenland)
- glacier access roads
- meltwater runoff
- darkening of nearby glaciers
Prospect.
Brucejack
[Fig. 3]
Au, Ag56.468 °N, 130.164 °W
(Canada)
- glacier access roads
- meltwater runoff
Approved in 2015.
Maarmorilik
(Phase Two expansion)
Zn, Pb71.094 °N, 51.027°W
(Greenland)
- meltwater runoff
- darkening of nearby glaciers
Prospect.
Svea Nord | Gruve
[Fig. 6]
C77.893 °N, 16.689 °E
(Norway)
- subglacial miningActive since 2001.
El Morro
(La Fortuna expansion)
[Fig. 4]
Cu, Au33.167 °S, 70.274 °W
(Chile)
- darkening of nearby glaciersActive since c. 2008.
Permit suspended in 2014.
Pascua Lama
[Fig. 5]
Au, Ag29.327 °S, 70.035°W
(Chile / Argentina)
- darkening of nearby glaciersActive since 2010.
Permit suspended in 2013.
KvanefjeldU60.963 °N, 45.957 °W
(Greenland)
- darkening of nearby glaciersProspect.
Red MountainAu, Ag55.970 °N, 129.721 °W
(Canada)
- proglacial and/or subglacial depositsProspect.
Grasberg [Fig. 7]Au, Cu4.060 °S, 137.146 °E
(Indonesia)
- darkening of nearby glaciers
- glacier removal to access subglacial deposit
Active since c. 1995.

Below are some site overview figures, they are available for distribution without attribution tags as well. I hope to make one for each project by the end of 2015. Content on this page can be cited as:

Colgan, W., H. Thomsen and M. Citterio. in press. Unique Applied Glaciology Challenges of Proglacial Mining. Geological Survey of Denmark and Greenland Bulletin.

Isua_Mine

Figure 1 – The Isua Mine in Greenland: Contemporary ice margins, proposed approximate pit area, and winter 2005/06 ice surface velocity vectors overlaid on a 2014 Landsat image.

Kumtor_Mine

Figure 2 – The Kumtor mine in Kyrgyzstan: Historic ice margins and contemporary mine area overlaid on a 2014 Landsat image.

Kerr-Sulphurets-Mitchell_Mine_Brucejack_Prospect

Figure 3 – The Kerr-Sulphurets-Mitchell Mine and Bruckjack Prospect in Canada: Contemporary ice margins, approximate mine surface areas, and proposed supraglacial access roads overlaid on a 2014 Landsat image.

El_Morro_Mine

Figure 4 – The El Morro mine in Chile: Contemporary ice margins and mine area overlaid on a 2014 Landsat image.

Pascua_Lama_Mine

Figure 5 – The Pascua Lama mine on the Chile/Argentina border: Contemporary ice margins and mine area overlaid on a 2014 Landsat image. The Valadero mine is also visible immediately south of the Pascua Lama mine.

Svea_Nord_and_Gruve_Mines

Figure 6 – The Svea Nord / Gruve Mines in Svalbard (Norway): Contemporary ice margins and underground mine area overlaid on a 2014 Landsat image.

Grasberg_w_label2

Figure 7 – Grasberg Mine in Indonesia: Contemporary mine area and ice margins in a 2003 Landsat image.

 

 

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Jumbo Glacier Resort: Certification Lapse?

Posted by William Colgan on October 09, 2014
Glaciers and Society / No Comments

The environmental assessment certificate of Jumbo Glacier Resort is set to lapse. The certificate was issued to Glacier Resorts Ltd. in 2004, to build an all-season ski resort in the Purcell Mountains, in Southwest British Columbia, Canada. The absence of a “substantial start” to construction by October 12 would mean the ten-year old environmental assessment certificate cannot be renewed. The Ktunaxa First Nation have contested the project, primarily over concerns it would threaten the Qat’muk Grizzly Bear population. The project would also develop four glaciers (Dome, Jumbo, Commander and Farnham) within a larger ski area. The completed resort would have twenty ski lifts, ferrying skiers up to 3,400 metres elevation, with a 6,300 bed ski village in the valley below. Unlike Europe, North America does not seem to have a particularly strong tradition of developing glaciers into skiing areas.

Huffington Post Canada: Time Running Out For Jumbo Glacier Ski Resort As Construction Deadline Approaches

Ktunaxa First Nation: Qat’muk

Jumbo Glacier Resort

 

jumbo_glacier_resort

Site of the proposed Jumbo Glacier Resort. (from www.qatmuk.com)

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Iceland Names “New” Glaciers

Posted by William Colgan on October 07, 2014
Climate Change / No Comments

This past week the Icelandic Meteorology Office named 130 glaciers on the Tröllaskagi Peninsula in north-central Iceland. Most of the new glacier names refer to local landmarks. Until recently, many of the previously unnamed glaciers had appeared to be white perennial snowfields, rather than blue ice glaciers, in satellite imagery. Retreating snow lines, however, have begun revealing underlying glacier ice since c. 1996. A glacier snowline marks the lowest elevation limit where year-round snow exists. Climate change is causing an upward migration of snowlines at most Arctic glaciers, due to increased surface melt during the summer season. So, although all of Iceland’s monitored glaciers are consistently exhibiting negative surface mass balance, and recent climate change has committed c. 35 ± 11 % of Iceland’s glacier volume (or c. 850,000,000,000 tons of ice!) to disappear, even in the absence of further climate change, some good new for Iceland: It’s glacier population is growing on paper!

Morgunblaðið: Um 130 nafnlausir jöklar

Mernild, S. H., Lipscomb, W. H., Bahr, D. B., Radić, V., and Zemp, M.: Global glacier changes: a revised assessment of committed mass losses and sampling uncertainties, The Cryosphere, 7, 1565-1577, doi:10.5194/tc-7-1565-2013, 2013.

Tröllaskagi_Peninsula_Iceland

The glaciers of the Tröllaskagi Peninsula, Iceland. (from GoogleEarth)

Iceland_glaciers_recent_surface_mass_balance

Recent surface mass balance observations from Iceland’s monitored glaciers. The ice loss of Tungnaarjokull, Langjokull and Hofsjokull SW now exceeds 3000 mm of water equivalent per year. (data from Mernild et al., 2013)

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