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Global Land Glacier thread for all land ice outside of Greenland and Antarctica


The_Global_Warmer

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So here is a neat thing, in terms of land ice. Outside the polar regions studies of glacial ice and cores from icecaps and other bodies often come from fairly high altitudes, in relatively isolated & exposed places that by and large are above the boundary layer and hence have the same qualifiers as 3000m+ met stations like those at Sonnblick and the Jungfraujoch vs. "where people actually live."

But there's also ice masses in caves -- "mini cave glaciers" -- some of which display seasonal deposition in their stratigraphy reaching back hundreds or even thousands of years. Image from a team at Ruhr Uni Bochum, layering clearly visible:

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Like ice caps, these can be cored (if awkwardly and not without difficult access). Image from a microbiology team at Uni Innsbruck.

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Kern (2013) in his article "Cave ice – the imminent loss of untapped mid-latitude cryospheric palaeoenvironmental archives," points out that cave ice offers two complementary advantages compared against surface alpine ice cores, which are that you get regional spread on account cave ice usually comes from nonglaciated terrain, and also the atmospheric chemistry, inclusion, particulate, and precip records can come from lower altitudes below the boundary layer.

However, cave ice studies are a relatively new field. This means that there's still a whole lot of work to be done sorting out how the specifics of deposition alter the chemical profile of cave ice, what kinds of ice flow and floor topography interactions are happening that mess up stratigraphy in nonobvious ways, periods of hiatus consequent to reduced deposition or increased ablation, and how air movement affects conditions for each specific cave -- so for instance Lava Beds Natl' Monument has some potentially long-lived ice masses, but interpreting past wastage in the cores is complicated by having to consider possible circulation changes resulting from passage collapse, or growth of the ice body itself. That's particularly pressing when your models for ice accumulation are founded on various mechanics of cold-air trapping & pooling. Any of you all who've had the joy of doing mine, tunnel, or sewer work can imagine how much fun it would be to reckon that out.

And there's other issues: one guy had his study complicated by the fact that in previous decades the locals had gone through and mined the cave glacieret for their iceboxes.

Consequently when dating or building a chronology from ice cores, you're really hoping for a straightforward stratigraphy lots of organic detritus to give points for radiocarbon dating, though it doesn't always doesn't give conveniently narrow values. So the team led by Hercman (2010), for their paper "The first dating of cave ice from the Tatra Mountains, Poland and its implication to palaeoclimate reconstructions," ended up relying on moths imprisoned in the ice wall, and then using historical investigations from the 1950s and earlier to constrain their RC dates. So doing, her team argue that the entrapped moths have dates likely in the 17th-18th centuries -- the LIA. Their team also noted a very strong unconformity in the ice layers, and they interpret the erosion boundary as representing melt occurring during the MWP, with older ice below and LIA-age above. Icewall of moth death from their paper:

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Stoffel and colleagues (2009) worked with Swiss cave ice to assemble a timeline using dendrochronology and RC methods to date tree embedded trunks, branches, etc., presenting their findings in their paper "Evidence of NAO control on subsurface ice accumulation in a 1200 yr old cave-ice sequence, St. Livres ice cave, Switzerland."

Their figures for stratigraphic analysis and chronology below the fold.

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They attempted to correlate periods of ice accumulation in St. Livees against reconstructions of past NAO indices, offering their study as a useful supporting proxy for long-term trends in cold season precip.

At any rate, like with small-ice-body / "ice patch" archaeology, cave ice is a relatively new field of paleoclimate research. As plain from the title of the Kern paper, its an archive similarly threatened by loss through melting. Worse, the recent strong negative mass balances are mostly affecting the top meter or so of these ice bodies, meaning that what's getting slagged off are precisely the layers needed for doing calibration against instrumental records.

Figure showing cave ice melt in caves with long-term investigation, from the 2013 Kern paper. Note the relative density of the observational record from Europe.

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  • 2 weeks later...

^^^^^ well for certain values of nice. s'nawnice, f'r t'snaw'n'ice to paraphrase bud neill

In other news SKS has a roundup, not much that's new but this survey of Marzeion et al (2014), covering attribution fractions.

http://www.skepticalscience.com/athabasca.html

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Part of Figure 1 from Marzeion et al. (2014), showing the increasing anthropogenic influence on glacier melt. The blue line is the running 20-year mean of the model ensemble and the shaded blue area is the standard error.

Upshot being anthropogenic contribution intensifies after 1920, becomes especially salient from ~1975 forward, in line with experiences analyzing borehole temps in Alps, and the wide error bars reflecting prior studies probing variability by Oerlemans and Roe.

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  • 1 month later...

Another find out of Norwegian ice: a ski, mostly intact, ~1300 years old.

Via

http://irisharchaeology.ie/2014/10/ancient-ski-discovered-in-norway/

attachicon.gifimage.jpg

Check out the binding:

attachicon.gifimage.jpg

 

Sokolow - your posts are consistently interesting and informative, and this one is no exception.  It must be terribly exciting for the Norwegian archaeologists to be finding these unique artifacts.

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Sokolow - your posts are consistently interesting and informative, and this one is no exception.  It must be terribly exciting for the Norwegian archaeologists to be finding these unique artifacts.

thx man :]

would love to shred some pow on that ironing board

i think its cool as heck that men & women spread all over the world have been mountaineers and alpine travelers, with specialized gear to do it, for millenia
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Big melt in Iceland.

 

 

http://williamcolgan.net/blog/?p=90

 

 

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!

 

 

 

 

Iceland_glaciers_recent_surface_mas_zps6

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  • 1 month later...

Couple of neat pix off of William Colgan's site Glacier Bytes, talking about 60 years of transport operations on ice & snow

http://williamcolgan.net/blog/?p=120

About sixty years ago, in September 1955, the US Army Corps of Engineers conducted the first test landings of wheeled military transport planes on a prepared snow runway at Site II, Greenland. The 3000 meter (10,000 foot) snow runway was prepared by repeatedly pulverizing and compressing the ice sheet’s snow surface with low ground pressure tractors. Driving the tractors from Camp TUTO to Site II, high in the ice sheet interior, took several days.

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"A wheeled C-124 Globemaster unloading on a snow runway at McMurdo Station, Antarctica, to deliver a smaller ski-equipped plane in 1956 (photo by Jim Waldron; http://icecores.org)"

Bonus: apparently here's what happens when a glacier advances into your ore processing facility

http://williamcolgan.net/blog/?p=14

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  • 2 weeks later...

ZAMG notes November 2014 checks in as the warmest on record since measurements began in Austria in 1767, 3.8C warmer than long term climo average, knocking off the 1926 record of +3.4C.

Meanwhile, snowfall across Austria has been lower than normal, with some high mountain regions such as the Hohe Tauern recording 27cm of snow versus an average value of 178cm.

alpen.wetter points out that with an average temp of 8.5C, beating 7.4C (1994) and 7.2C (1926) 2014 is by far the warmest November at Innsbruck since obs began in 1777; it is also the first time in the history of the Uni-Innsbruck weather station no frost was recorded in November.

Innsbruck also recorded powerful, long-duration föhn weather with hurricane strength winds at altitude -- nice pictures from alpen.wetter -- and the warm & sunny regime managed to slag 200cm of late October and early November snowfall

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http://alpen-wetter.blogspot.com/

Summer conditions are most influential for glacier mass balance, and late summer 2014 was relatively cool and damp, which means that going into winter 2014-15 some glaciers in Austria may even record a small positive balance in an otherwise warm year.

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However, the stength of cool and moist summers is they protect accumulated winter pack -- so here's hoping for white peaks and plenty of ski powder in the yodelzone during the coming months.

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One of the great things about southern CA is you can go from mediterranean warmth to arctic cold in a few hours' drive; along with the San Franciscos of northern AZ, the peninsular ranges of the LA basin mark out the reach of arctic-alpine tundra in the USA.

Makes for great climbing year-round.

How about glaciers? Geologists attributed landforms of the San Gabriel. San Jacinto, and San Bernardino mountains to pleistocene glacial activity at the beginning of the 20th century, and the best standing summary & field study is found in:

Sharp, R. P., Allen, C. R., & Meier, M. F. (1959). Pleistocene glaciers on southern California mountains. American Journal of Science, 257(2), 81-94.

With additional modern radionuclide work done in the early oughts to try and pin down the chronology.

Sharp et. al. found that the most robust glacial landforms were found exclusively in the San Bernardinos, grouped around Mt. San Gorgonio 11503'), with accumulation areas largely between 10300'-11300', glacier tongues extending to a lowest elevation of 8700'.

You'll probably be able to lay a wager on where a few of these glaciers were just by looking at this aerial pic from the San Gorgonio Wilderness Association:

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And indeed that's where Sharp et. al located them -- look at Charlton - Jepson - Gorgonio

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The modern resurvey and cosmogenic radionucleide exposure dating by Owen & Finkel (2003) largely supports Sharp & crew, and refines their timeline into a chronology marked by 4 stages of glacial advance, beginning ~20ka, with the last and smallest terminating in the middle holocene, ~5ka.

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The Sharp et. al paper didn't validate prior claims to glacial activity in the San Gabriels, noting that the supposed glacial features had alternative explanations in underlying geomorphology and were in most cases at too low an altitude; the highest peak in the range, Mt San Antonio (10068'), is below the lowest altitude for glacier heads in the Bernardinos, it N-NE slopes show no particular evidence of icework, and there is no cause to propose significantly different climo than the Bernardinos.

How about San Jack? San Jacinto (10834') is high enough -- but as anyone has seen it knows, its north face is too dang steep to hold a lot of accumulation, snow creek being basically one long, foul, boulder-strewn brush-choked avalanche chute / rockfall gully plunging 7000 feet to the desert floor.

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Other possible glacial sites in the San Jacintos (in the hollow below Jean Peak, for example) have been proposed, but afaik never convincingly demonstrated.

Owen and Finkel point out based on treeline and pack depth work done by Minnich that snow accumulation in the Bernardinos is driven by powerful flow from the S-SW; snow from storms tracking in off the Pacific basically falls sideways in the Bernardino peaks to begin with, tends to get lofted off windward slopes into the lees of ridgelines, where accumulation is further aided by avalanche. Transport in other directions is limited because outside storm conditions, the climo of the transverse aids compaction and wind profiles don't support snow transport in other directions.

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All of which builds dense pack, and which Minnich argues shapes biogeography of the Bernardinos through tree kill. Even in these latter days we see perennial snow in the Bernardinos & ice hiding under boulders in the Jacintos; shave off a couple of few degrees C and you can see how we'd get to the glaciers of Los Angeles.

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  • 1 month later...

thanks yall ^^^

Neat dual posts from Dan McShane at Reading the Washington Landscape and Mauri Pelto at From a Glacier's Perspective.

http://washingtonlandscape.blogspot.com/2015/01/mauri-pelto-notes-that-anderson-glacier.html

https://glacierchange.wordpress.com/2015/01/09/anderson-glacier-olympic-mountains-washington-disappears/

McShane is riffing on Pelto's post about the disappearance of Anderson glacier, Olympic mountains, Washington. He points out that while Anderson has retreated rapidly into oblivion, two nearby glaciers, particularly Linsley's glacier, have not:

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McShane:

Anderson Mountain had three glaciers. The other two glaciers are still in tact. The Eel Glacier is oriented to the north and its accumulation area is higher than the former Anderson Glacier. The Linsley Glacier is oriented to the south but also has a higher elevation accumulation area than the former Anderson Glacier. The few hundred feet has made a considerable difference as the climate warmed.

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Interesting illustration in light of the stuff about aspect and accumulation area posted upthread,

Bonus pic via Jamie Woodward's twitter:

Lunch on a beautifully stratified glacier table on the Pasterze #Glacier in Austria in 1910

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As has come up repeatedly in this thread, images of glacial retreat over time -- such as the one below -- provide some of the most iconic representations of a rapidly changing climate.

ZYdqTkn.jpg

Less well known by the public are the ways in which glacial retreat is affecting canine populations:

Two examples of profound canine changes from the 19th to 21st century

Phac0vE.jpg

8oDph3Y.jpg

There is only one conclusion to be drawn:

The dogs are melting.

LmMO33E.jpg

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The difference between 1924 and 1985 just reinforces that this is a long duration warming... spanning hundreds of years.

Or rather is an example of how sensitive these structures are to small shifts in temperature. The early 20th century warming has been attributed to natural causes however it's irrelevant.

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  • 6 months later...

Huh weird behavior from the post editor

Quick take: they're melting

Slightly less quick take: 1. The melt can be causally attributed to climatic drivers 2. Late 19th and early 20thc melting falls within estimated bounds of natural climate variation 3. Late 20thc and early 21stc requires anthropogenic forcing to be explicable 4. the rate of melt is increasing globally.

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By way of situating that in a longer timeframe:

QSR 111 Solomina et al

Holocene glacier fluctuations

https://www.geo.umass.edu/climate/papers2/Solomina_QSR_2015.pdf

5.5. Modern glacier retreat in the Holocene context

Perhaps of most significance, there is much evidence of unusual glacier behavior in the last century (and especially in the last few decades) in many regions compared to Holocene glacier changes. The recent exposure of organic material buried under the ice since the early to mid Holocene in some regions is unprecedented for at least the last four to five millennia and in some areas (e.g. in the Canadian Arctic: Miller et al., 2013) possibly since the Last Inter- glacial. The retreat is occurring at very high rates, is almost uni- versally global in scale and is acting during an interval of orbital forcing favorable for glacier growth, rather than degradation. This highlights the remarkable consequences of anthropogenic forcing on glaciers worldwide

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  • 2 weeks later...

Via William Colgan's blog:

http://williamcolgan.net/blog/?p=352

A brewing company teams up with glaciologists, offering to fund research in exchange for the recovery of five liters of ice from 1962, year of the company's founding.

http://www.theglobeandmail.com/news/british-columbia/bc-scientist-teams-up-with-kokanee-brewer-on-glacier-research/article25982276/

vVAksxp.jpg

Colgan sends them a glowing letter:

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.

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In other news its been a extremely melty year for glaciers in the pac-NW;

http://blogs.agu.org/fromaglaciersperspective/2015/08/20/disastrous-year-for-north-cascade-glacier-mass-balance-snowice-economy/

Pelto reports that at his study sites they measured an average ablation of 7.5cm of ice per day

While I haven't seen anything pop up about the alps -- austrian measurements come in in the fall from ZAMG -- its not gonna be a good one. I wonder how it'll compare to summer of 2003.

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