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Thread: mammoths, lice in the fur of climate claims.

  1. #1 mammoths, lice in the fur of climate claims. 
    Forum Sophomore andre's Avatar
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    The Discovery channel feature "Raising the Mammoth", starring my buddy Dick Mol, is about the discovery and excarvation of the Jarkov Mammoth mummy, in northernmost Siberia. It was world news in 1999.

    http://www.learnersonline.com/weekly...ek43/index.htm

    http://www.cq.rm.cnr.it/elephants2001/pdf/305_309.pdf

    Now, this would be an important find for a further understanding the paleo climate during the ice age and we would be informed how this insight would progress. However, Mammoths are out now, the much more stunning discovery of the Yukagir mammoth did not make it to the interest of Discovery Channel at all, even the exposure of mummy at the EXPO 2005 in Japan barely reached the press and it did not trigger any climate insight expectations at all. Why would that be?

    The Yukagir mammoth:



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    Dick Mol is on the left here:



    He is always around when remains like this are discovered.

    Another stunning discover last year, going by almost unnoticed:




    The problem was that the mammoths did not live like this:..


    but much more like this:



    See also this

    That's the reason why the mammoths are only tucked away deep inside the IPCC climate reports with a small ambigeous remark. But in reality they debunk the basics of paleoclimatology, and that's not nice of course.


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    The mammoths basically tell us that this is not true



    for the simple reason that the mammoths were must abundant in places where it's way to cold to live now, in some of the periods that the Northern Hemisphere at was yet thought to be 20 degrees colder than today, notably the Younger Dryas.

    Source

    It's not that the mammoths could not survive extreme cold temperatures but it is simple because grass refuses to grow in the cold and elephants of that size eat about 200 kg grass a day.

    But if that's not true then the whole climate business would topple, so that's why the mammoths are out.
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    Not sure what your point is, but you are aware of course that there were (at least) two species of mammoth, one, the woolly mammoth adapted to colder climates and the other, the Columbian mammoth adapted to much warmer climes.
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    Quote Originally Posted by Bunbury
    Not sure what your point is, but you are aware of course that there were (at least) two species of mammoth, one, the woolly mammoth adapted to colder climates and the other, the Columbian mammoth adapted to much warmer climes.
    Again, the point is in the grass, not growing enough in the cold to sustain large herds of megafauna, but more importantly the mammoth is the high visibility member -poster child- of the 'ice age' but at same time they shared the steppes with wild cows, horses, antelopes, etc, not really renowned for being deep freeze dwellers.
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    But the grass did grow, at least in some parts of Siberia.

    http://www.sfu.ca/~qgrc/zazula_2003b.pdf
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    Modern caribou migrate 3200km round-trip every year. Presumably mammoth did likewise, maybe farther.

    Was the arctic more or less temperate during the ice age? I would guess that yes annual average was colder but seasonal extremes were greater than now. Grass does "refuse to grow in the cold" but remember "the cold" is not without pronounced seasons! So we have good incentive to migrate and also bulk up against winter scarcity.

    Some - perhaps most - mammoths died at the northern summer extreme of their range, where we'd expect just a few months thaw and winters cold enough to freeze a mammoth solid. I guess most accidental deaths were caused by muddy, impassable spring terrain. Rivers appear, the frozen ground turns to slush or lake, herds get stranded. Note that most human transport across the high arctic is done in winter, when the ground is solid.

    Anyway, the mammoth's tusks are obviously suited to clearing snow, as the grazer rocks its head side to side.
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    Quote Originally Posted by Bunbury
    But the grass did grow, at least in some parts of Siberia.

    http://www.sfu.ca/~qgrc/zazula_2003b.pdf
    Exactly! and so did the Greater Burnet found back in the guts of the Yukagir mammoth. But the winterhardiness of this species is only to USA zone 4.

    Yet this mammoth was found in the Arctic tundra of Northern Yakutia, Siberia, aged just prior to the last glacial maximum.
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    Quote Originally Posted by Pong
    Modern caribou migrate 3200km round-trip every year. Presumably mammoth did likewise, maybe farther.
    Daniel Fischer of An Arbour Michican did extensive research of isotopes in the growing rings of the tusks of the Mammoth. Unfortunately he did not publish much on the subject but he could not find a consistent annual migration pattern of the Siberian Mammoth, although he did find a biannual pattern change in female cows.

    Was the arctic more or less temperate during the ice age? I would guess that yes annual average was colder but seasonal extremes were greater than now.
    Still a long shot to have the average tempeature 20 degrees colder than nowadays and have grass growing at places where it can't grow now, due to the cold

    Anyway, the mammoth's tusks are obviously suited to clearing snow, as the grazer rocks its head side to side.
    Fairy tale. The tusks of the female woolly mammoths were about one to two feet long.



    Moreover the retrieval of certain beetle remains confirm that the winter snow cover was minimum. I'll get that link later. The winters during the last glacial maximum were not extreme cold in Siberia, but hyper arid - no snow.
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    Quote Originally Posted by andre
    Quote Originally Posted by Pong
    Was the arctic more or less temperate during the ice age? I would guess that yes annual average was colder but seasonal extremes were greater than now.
    Still a long shot to have the average tempeature 20 degrees colder than nowadays and have grass growing at places where it can't grow now, due to the cold.
    True.

    Quote Originally Posted by andre
    Quote Originally Posted by Pong
    Anyway, the mammoth's tusks are obviously suited to clearing snow, as the grazer rocks its head side to side.
    Fairy tale. The tusks of the female woolly mammoths were about one to two feet long.

    Elephants: The females herd, while the males are solitary. So how would they migrate differently, with arctic seasons? I think you'd see the female herds making farther more predictable journeys, perhaps to traditional calving ground destinations far south; while the solitary males would wander and linger farther north than calves could endure, often finding themselves snowed in. If so, the tusks make perfect sense.

    If that's true, we'd expect the finds to show herds of calves & females isolated from single male remains. Also gestation period must fit the pattern (not 22 months as in elephants). And it also makes the mammoths vulnerable to predators smart enough to camp the calving grounds... like humans. Once humans learned to preserve meat, we'd take a sedentary lifestyle and slaughter cows and calves each winter, easy. Bad news for the mammoth population!

    EDIT: No wait, I'm backwards. Calving must be north in summer. So gestation ought to span about 12 or 24 months. Yet we want rutting and calving separated.

    In any case for humans to catch the herds at their most vulnerable we'd be camping north, and who wants to stay the winter?
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    The winters during the last glacial maximum were not extreme cold in Siberia, but hyper arid - no snow.
    Are you aware that Antarctica is the largest and driest desert in the world, yet it is also the coldest continent. Cold and lack of snow are not mutually exclusive.

    Wiki on Siberia:

    "Almost all the population lives in the south, along the Trans-Siberian railroad. The climate here is continental subarctic (Koppen Dfc or Dwc), with the annual average temperature about 0 ℃ (32 ℉) and roughly −15 ℃ (5 ℉) average in January and +20 ℃ (68 ℉) in July.[11] With a reliable growing season, an abundance of sunshine and exceedingly fertile chernozem soils, Southern Siberia is good enough for profitable agriculture, as was proven in the early twentieth century.

    The southwesterly winds of Southern Siberia bring warm air from Central Asia and the Middle East. The climate in West Siberia (Omsk, Novosibirsk) is several degrees warmer than in the East (Irkutsk, Chita). With a lowest record temperature of -71.2 °C (-96.1 °F), Oymyakon (Sakha Republic) has the distinction of being the coldest town on Earth. But summer temperatures in other regions reach +36...+38 °C (97-100°F).
    "

    I am guessing that southern Siberia could well have had sustained grass lands during the last glacial period. Also, the sea level was up to 120 meters lower during the last glacial period, expanding the coast line substantially, providing warmer low lying climates.

    Wiki on Mastadon:

    "Though their habitat spanned a large territory, mastodons were most common in the ice age spruce forests of the eastern United States, as well as in warmer lowland environments.[4] Their remains have been found as far as 300 kilometers offshore of the northeastern United States, in areas that were dry land during the low sea level stand of the last ice age"

    Siberian Grass lands (Ukok_Plateau):



    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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    Quote Originally Posted by andre
    Exactly! and so did the Greater Burnet found back in the guts of the Yukagir mammoth. But the winterhardiness of this species is only to USA zone 4.

    Yet this mammoth was found in the Arctic tundra of Northern Yakutia, Siberia, aged just prior to the last glacial maximum.
    Unfortunately the link mentions only fungi - nothing that I could see there about the Greater Burnet. Do you have another reference?
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    Quote Originally Posted by Pong
    Quote Originally Posted by andre
    Still a long shot to have the average tempeature 20 degrees colder than nowadays and have grass growing at places where it can't grow now, due to the cold.
    True.
    That's the essence, mammoth discussions are nice but it's all about the falsification of the Greenland paleo thermometer.

    Quote Originally Posted by Pong
    In any case for humans to catch the herds at their most vulnerable we'd be camping north, and who wants to stay the winter?
    Apparantly projecting the North American situation onto Siberia, but there is no evidence whatsoever that humans hunted mammoths in Siberia extensively. Actually the last mammoths died out on the Taymir peninsula, the northernmost portion of Siberia, shortly after the termination of the Younger Dryas. But no trace of humans out there in that period.

    Actually there is a single artifact from Russia (other place other time), a mammoth vertebra with traces of a fluted point penetrating. However the position is such that it looks to be target practice, rather than hunting despite the talk about the latter.

    http://www.yukonmuseums.ca/mammoth/abstrt-z.htm

    Scroll down to the last abstract.
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    Quote Originally Posted by KALSTER
    Are you aware that Antarctica is the largest and driest desert in the world, yet it is also the coldest continent. Cold and lack of snow are not mutually exclusive.
    Of course not, but those factors temperature and humidity are rather independent. See also the Serengeti in your case. Moreover there is now a body of evidence about the climate out there in the past. More later.

    Quote Originally Posted by KALSTER
    Wiki on Siberia:

    "..Almost all the population lives in the south,...
    But we are talking about North Siberia along the Arctic coastline. Actually there were even Mammoths on October revolution island, some 700 miles from the North Pole.
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    Quote Originally Posted by Bunbury
    [Unfortunately the link mentions only fungi - nothing that I could see there about the Greater Burnet. Do you have another reference?
    It's only in that publication, I made a screenshot-copy of the table with the inventory of the pollen remains in the guts:

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    Could you more clear in what it is you are saying? I'm not getting it. I gather that you claim that the paleoclimate record is wrong somehow and the evidence is something to do with mammoths? What exactly? Are you saying we did not emerge from an ice-age some 10,000 years ago? That there was no ice age? That mammoths did not live on the margins of the ice? Or what?
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    Quote Originally Posted by Zwirko
    Could you more clear in what it is you are saying? I'm not getting it. I gather that you claim that the paleoclimate record is wrong somehow and the evidence is something to do with mammoths? What exactly? Are you saying we did not emerge from an ice-age some 10,000 years ago? That there was no ice age? That mammoths did not live on the margins of the ice? Or what?
    I'm trying to say that the theories about the paleoclimate, ice age etc, like the ice cores are all based on suppositions which are in line with the general climate scaremongering. Most notably the isotopes in the ice cores which appear to tell us that northern hemisphere temperatures fluctuated 10-20 degrees celsius. So, it is supposed to be 'warm' now, and looking at the high arctic tundra of North Siberia it's just what you expect over there so close to the North Pole, at the fringe of area where just a little life is still possible in the summer months. Now if in the ice age (and Younger Dryas) it was 10-20 degrees colder, then you would expect that area to be absolutely uninhabitable, staying below freezing year round.

    But the mammoths are jumbo evidence that it was not like that at all, as they were thriving on productive grassy steppes in large numbers under these impossible conditions of it being 10-20 degrees colder.

    That's the problem.
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    all based on suppositions which are in line with the general climate scaremongering.
    To what end would that be?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
    "All people know the same truth. Our lives consist of how we chose to distort it." - Harry Block
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    Quote Originally Posted by andre
    Now if in the ice age (and Younger Dryas) it was 10-20 degrees colder, then you would expect that area to be absolutely uninhabitable, staying below freezing year round.
    "Year round"? But you know the seasons would have been more pronounced. I mean, north pole you've got 24 hr. sunlight half the year and all that's moderating it (besides the half-assed angle) is air and ocean gyres. So what if they're disrupted? Did you know that dropping sea to ice-age level isolates the Arctic Ocean from Pacific Ocean? That's a recipe for extremely pronounced seasons in the arctic.

    And of course mammoths migrated long distances. So nothing odd about finding remains where winter temps fell to -40 or whatever.
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    Quote Originally Posted by Pong

    And of course mammoths migrated long distances. So nothing odd about finding remains where winter temps fell to -40 or whatever.
    That would be a warm winter now, but nevertheless rather cold for the Greater Burnet (Sanguisorba officinalis) found in the guts of the Yukagir mammoth, as said. This mammoth was dated about 18350 carbon years ago, which converts to about 22,000 calendar years, at the onset of the Last Glacial Maximum.

    Incidentily check out this abstract:

    http://www.yukonmuseums.ca/mammoth/abstrmol-mor.htm

    Scroll down roughly halfway:

    The find of Larix is especially interesting, because the site where the Fishhook Mammoth was found is situated at about 200 kilometres north of the present timber line.
    But this was about 20,620 carbon years ago or 24,700 calendar years, with the last glacial maximum approaching.

    It's not what the mammoth can or cannot do, it's what the evidence tells us.
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    Where is Yakugir? I can’t find it in my world atlas or on the internet. I think it might be somewhere in the general area of Yakutsk.

    Here’s Yakutsk: http://en.wikipedia.org/wiki/Image:Lena_watershed.png

    Here’s a map showing the extent of glaciation during the last ice age.

    http://upload.wikimedia.org/wikipedi...tation_map.png

    The ice sheet comes nowhere near Yakustk, and even north of Yakutsk all the way to the Arctic Ocean is free of permanent ice. It’s classified in this map as an Arctic desert. I’ve been in an Arctic desert on the North Slope of Alaska. There’s lots of vegetation including Arctic cotton, dryas, dwarf willow, various grasses and sedges. There are thousands of caribou and there are foxes and lemmings. There’s also water, in circular ponds all over the place. (The term desert refers to lack of rainfall, not necessarily to absence of water on the surface.)

    Finally, here’s something on the willow twigs found in the Yakugir mammoth’s gut:

    Rings
    To help find out, the team sliced thin cross-sections of the willow twigs. The thickest twig was less than a fifth of an inch in diameter, yet it bore more than 20 annual rings. That growth rate is even slower than that of modern Salix arctica, indicating the mammoth's climate was even more austere than that of northern Greenland, where S. arctica lives today. The cross-sections were even clearer as to season of death: When the mammoth ate the willow, the first spring vessels of the outermost rings were just forming—a clear sign that he had died in early spring.
    http://www.pbs.org/wgbh/nova/science...3-mamm-nf.html

    So the mammoth perhaps lived in an environment colder than northern Greenland is today, but where vegetation and water were nevertheless freely available. Presumably when the water froze in the winter the creatures had migrated further south as Pong has already indicated.
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    Quote Originally Posted by Bunbury
    Where is Yakugir? I can’t find it in my world atlas or on the internet. I think it might be somewhere in the general area of Yakutsk.
    The Yukagir mammoth was found here:


    Wasn't I talking about the Arctic ocean area?

    Here’s a map showing the extent of glaciation during the last ice age.

    Right, this demonstrates exactly the problem with paleoclimate and geology; when things get debunked the old stuff lingers on and on, obstructing and obscuring the real situation and preventing progress.

    compare Hubberten et al 2004

    The real researched extend of the last Weichselian glaciation during the Last Glacial Maximum:



    Notice that the Jarkov and Fishhook mammoths were found around dot #2, that there also fossils found around dot #4 and that the Yukagir finding place is just off the map around where it says 140 degrees E

    Finally, here’s something on the willow twigs found in the Yakugir mammoth’s gut:

    Rings
    To help find out, the team sliced thin cross-sections of the willow twigs. The thickest twig was less than a fifth of an inch in diameter, yet it bore more than 20 annual rings. ...
    Affirming the consequent fallacy. Go to the higher grounds and find some small pinus trees growing on dry rocky slopes. You need a very strong magnifying glass to count year rings. There may be dozens of rings going into the size of one year ring of a normal growing specimen. Yet there was no ice age at that slope.

    Presumably when the water froze in the winter the creatures had migrated further south as Pong has already indicated.
    Migrated appears not that effective as for instance the average winter temperatures of Jakutsk down in the south are in the -40/-50 range
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    Quote Originally Posted by andre
    Yet there was no ice age at that slope.
    Why do you conclude that? All your map shows is that the points are near the maximum expenses of the ice--that doesn't rule out that grass and willows continue to grow near that margin--not in the least. Even today grass and low arctic shrubs can grow adjacent to glaciers. They might have even been preferable, considering the 24 hour sunshine and abundant water.
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    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by andre
    Yet there was no ice age at that slope.
    Why do you conclude that?
    Because I'm talking about a random rocky slope now. If you find dwarf pines there now, chances are that the rings are very tight together, proving that low temperatures are not exclusively reason for dwarf growth

    All your map shows is that the points are near the maximum expenses of the ice--
    The map demonstrates that old ideas about Siberian ice sheets are superseded. But also note that the Jarkov and Fishhook mammoth are older than the last glacial maximum (24ka). It is believed that the ice advanced from the Ferroscandian base around 22ka and reached the maximum extend ~17ka, hence 9000 years after the Jarkov/Fishhook period. Yet the ice core isotopes were long at it's minimum:



    And hence it should still have been 10-20 degrees colder than today when the mammoths roamed the grassy steppes, productive enough to support many large grazers/

    that doesn't rule out that grass and willows continue to grow near that margin--not in the least. Even today grass and low arctic shrubs can grow adjacent to glaciers. They might have even been preferable, considering the 24 hour sunshine and abundant water.
    They do but at a very slow pace, Tundra vegetation takes very long for recovery of grazing. Hence the amount of grazers is minimum.
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    Quote Originally Posted by andre
    Because I'm talking about a random rocky slope now. If you find dwarf pines there now, chances are that the rings are very tight together, proving that low temperatures are not exclusively reason for dwarf growth
    And no one says it is does. Tree ring growth is a measure of that season's growing success for that species--it's usually a pretty good proxy for summer temperatures, but it can be effected by other factors such as moisture, max daily temperatures, desease etc.
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    Quote Originally Posted by Lynx_Fox
    Quote Originally Posted by andre
    Because I'm talking about a random rocky slope now. If you find dwarf pines there now, chances are that the rings are very tight together, proving that low temperatures are not exclusively reason for dwarf growth
    And no one says it is does. Tree ring growth is a measure of that season's growing success for that species--it's usually a pretty good proxy for summer temperatures, but it can be effected by other factors such as moisture, max daily temperatures, desease etc.
    So it was just another red herring and we are left with questions like: Why could there be a larch needle in the guts of the Fishhook mammoth in the northernmost part of Siberia, 200km north of the present timber line, shortly before the last glacial maximum, when the temperature was allegdly 10-20 colder than today.

    Very particular that this did not trigger any scientific curiousity, just efforts to circumnavigate it. Clear why the mammoths are out. They overthrow our climate spins.
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    I think, Andre, you're trying to ignore seasons.

    And the air and ocean circulation was likely very different. I'm not so sure a place farther north must be colder annually either.
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    Quote Originally Posted by Pong
    I think, Andre, you're trying to ignore seasons.

    And the air and ocean circulation was likely very different. I'm not so sure a place farther north must be colder annually either.
    It would be very interesting to learn how we could increase the current annual temperatures out there in whatever seasonality to sustain the abundant megafauna and simultaineously decrease the temperatures 10-20 degrees in whatever seasonality to satisfy the interpretation of the isotopes of the ice cores.
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    Quote Originally Posted by andre
    Quote Originally Posted by Pong
    I think, Andre, you're trying to ignore seasons.

    And the air and ocean circulation was likely very different. I'm not so sure a place farther north must be colder annually either.
    It would be very interesting to learn how we could increase the current annual temperatures out there in whatever seasonality to sustain the abundant megafauna and simultaineously decrease the temperatures 10-20 degrees in whatever seasonality to satisfy the interpretation of the isotopes of the ice cores.
    There are several ways that can happen. You're trying to extrapolate an average temperature to a specific local condition. If it was a South facing slope, that fact alone would account for significantly warmer surface average than the surrounding terrain, slope microclimatology temperatures of 10-15F higher are not uncommon. You can see the effect in just about any alpine terrain (go see some) or find it in a gardening books when considering plant tolerance by zone etc.

    The other mistake is ruling out seasons. Taking a simple example, if the Winter is 20 F colder, but the summer 10F warmer the plants would thrive during that brief summer even though the AVERAGE is quite a bit colder. Regional conditions could create this type of condition simply by being more continental--even if global seasonal variations were no larger.
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    Quote Originally Posted by andre
    annual temperatures out there in whatever seasonality
    Do you know what you're saying? It seems you're confusing annual and seasonal temperatures. A farmer doesn't care that the average temperature 24/7/365 is -5 when he really wants to know the daytime sunlight conditions during growing season. Migrating fauna don't care how cold it is in winter, if they only visit for a few summer months.

    AFAIK ice cores only tell us about the ice laid up. And if ice accumulates over years that doesn't mean the ambient temperature remained subzero every hour, day, or month.

    Build a large snowman this January and see how long it lasts into spring. What does a core taken in March tell us about the air temperature in February?


    In addition to what Lynx_Fox said about local climates/microclimates, we should remember that a huge ice sheet is going to have focused streams of cold air running out of it, and these must drive tropical air in turn toward the poles. Wherever those warm currents hit, we'll have a "Pineapple Express" effect... why my part of Canada enjoys green lawns and roses blooming all winter. Now, with Berengia barring Arctic-Pacific seawater exchange, and the North Pacific Drift kaput 'cause its source is shallows, and a huge misshapen lump of ice up north, who can guess the air currents?
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    I found this in the Paleoenvironmental Atlas of Beringia.
    http://www.ncdc.noaa.gov/paleo/parcs...gia/index.html
    (Lots of data - not user-friendly)

    During Pleistocene ice ages, winters were severe in Beringia, but thin snow cover allowed grazing mammals to find sufficient winter forage. Dominant "ice age" grasses and sedges (e.g., Kobresia) retained enough nutrients in their above ground tissues to allow survival of grazing animals through the winter. Ice-age climate was relatively arid, and it is likely that airborne dust (loess) from glacial outwash plains contributed abundant nutrients to soils. Vegetation was grassy, with few peat-forming plants. Willows were the most abundant shrubs in the landscape.
    http://esp.cr.usgs.gov/research/alas...s/figure36.jpg
    T. Ager photo.

    The Mean Coldest Monthly Averaged Temperature 24kA ago in Beringia was 10 deg C below current temperatures according to this:

    http://www.ncdc.noaa.gov/paleo/parcs...ges/mcrmin.gif
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  33. #32  
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    Good find Bunbury, reminds me of how MuskOx live today-- driven back to the very margins of survival in places like Northern Greenland where they subsist even through the winters by eating the thin grasses that grow between the Greenland ice cap and the icebound Arctic Ocean.
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  34. #33  
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    How does a mamoth freeze solid with nondigested food in its belly standing up?
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