May 10, 2012

Video: visualization of ice sheets and sea level on Europe since LGM

Hat tip to Marnie for this great finding. 

The video-animation has been developed by Adrian Meyer and Karl Rege, from the Zurich University of Applied Sciences.

It begins at 19,000 BCE (or 21,000 years ago and extends several millennia into the future according to predictions). Most of the action is concentrated right after c. 0:50 mins, which corresponds with 10,000 BCE (latest Upper Paleolithic and semi-official beginning of the end of the Ice Age).


 


11 comments:

  1. The map illustrates nicely the fact that haplogroup V found in the Saami had to arrive in Scandinavia sometime after the CP Neolithic.

    ReplyDelete
    Replies
    1. I thought it was widely acknowledged that it had arrived to Lappland only via the Volga, from where the Finnic peoples expanded.

      Delete
    2. Saami genetics pretty clearly show a dual source some of which is not from the Volga (with hg V being on of the pieces of evidence pointing to that conclusions). Latvians are probably closer genetically to the proto-Finnic people expanding from the Volga than the Saami. It also isn't obvious that the Saami were originally Uralic language speakers - this may have happened only after their Scandinavian ethnogenesis and replaced a prior language of these people (or at least a prior language of one of the populations that contributed to these people).

      Delete
    3. From what I remember being taught by people more knowledgeable, that is not the way you say. It'd be problematic for me to track the relevant materials but I'm quite sure that, at least some years ago, it was quite apparent that Saami and Finnish V had migrated via the Volga. These populations have quite low genetic diversity at local levels (Finnish may be made up of several smaller distinct, isolated populations) and some of their lineages have suffered obvious founder effects. That's the case of V: huge amount, low diversity.

      Also you seem to speculate that origin of Finnic languages would not be in Volga-Urals-Siberia but that is what seems to be the case tracking the archaeological data (in addition to the genetic data). The Finnic ethnogenesis happened there and then they spread Westwards towards the Baltic and Northern Scandinavia after transforming the reindeer hunter specialization of their Siberian partial ancestors into reindeer husbandry skill and probably interacting culturally in other ways (language) with Proto-Indoeuropeans.

      That's how I see it.

      Delete
  2. I would take this visualization as more theater than science. The Arctic was likely ice-free in summer around viking times, and also several times earlier in the holocene. Furthermore, climate heretics who say the recent warming is the result of solar (not CO2) activity, now point to weakening solar activity as the basis for predicting severe cooling for the next century. Another problem I have with the video is the absence of the Younger Dryas event.

    ReplyDelete
    Replies
    1. Can you document your claim about the Arctic being ice-free in Viking times?

      The authors are qualified scientists. Of course nobody is free from error but I'm sure that they have tried to be as accurate as possible.

      "Another problem I have with the video is the absence of the Younger Dryas event."

      Yes, that one I have spotted as well. It is documented that somewhere like Ireland, which was already quite unfrozen, was plunged again into extreme cold in the matter of months.

      Naturally the future are predictions, which are much more arguable. I do think that global warming caused by industrialization is very very real and a major problem that threatens our continuity as species (as well as that of many other animals and plants) but well, that is certainly not the focus of this post.

      Delete
    2. Manju - The ice-free summer arctic data is not in a single paper. Instead, it is spread over several studies of Canadian driftwood and diatom ocean sediments, plus shipping maps and documents through the centuries, plus anecdotes by famous travelers, including Marco Polo. (Marco Polo recorded a sea voyage where the northstar and magnetic north were in opposite directions. He could not figure it out, but we can interpret his observation as meaning that he was in the arctic ocean north of Canada between geographic and magnetic north.)

      Delete
    3. and... the arctic ocean was almost ice-free in the 1930s. There is a famous photograph of a US sub surfacing at the northpole around that time (in early winter), showing that significant open leads of water existed then.

      Delete
  3. "I do think that global warming caused by industrialization is very very real and a major problem that threatens our continuity as species"

    Agree. All the other rubbish we're pumping into the air and into the water poses a far greater problem. Sorry about the sidetrack. Carbon credits are designed to keep the already wealthy in the manner to which they have become accustomed.

    ReplyDelete
  4. What this nice visual does not convey: It was not a matter of "ice-sheets vs ice-free land".

    Most of Europe was unlivable tundra at the Last Glacial Maximum.

    ReplyDelete
    Replies
    1. Probably not. There must be studies of climate and vegetation variation but it's clear that tundra was not dominant but more what the call "steppe-tundra" which hosted more vegetation and animals.

      From Wikipedia: "Ground cover amounted to no more than about 50%, with mainly herbaceous plants but a few scattered low shrubs and occasional stunted trees in sheltered spots. (...) At [some European] temperate latitudes intense sunlight and loess soils permitted a high level of bioproductivity; mosses, lichens, grasses, and low shrubs that fed mammoths, horses, bison, giant deer, aurochs and reindeer".

      There were two main kinds:
      1. Dry steppe-tundra, quite hostile, in Northern France and most of the Balcans - areas that were very thinly populated if at all.

      2. Loess steppe-tundra, more benevolent, in the Rhine-Danube and Dniepr-Don regions, which was quite productive and hosted continuous populations (even if surely shrinking in the LGM) for all the UP.

      Loess itself is a soil formation created by grass and wind. There's no loess without grass, except as fossil residue.

      Finally the Franco-Cantabrian region was, I understand, a more mixed ecosystem because of its more temperate location and the availability of both steppe-tundra and other ecosystems, with woodlands, mountain niches, etc.

      In the Late UP period even the areas of Northern Europe very much near the Ice Sheet border, including the (now submerged but then important) Doggerland, were inhabited by people with a techno-culture different from that of the more mainstream Magdalenian one: the Hamburgian-Ahrensburgian culture, precursor of the Epipaleolithic seagoing culture of Maglemöse, which existed at both sides of the North Sea.

      I speculate that this distinction may explain some genetic and phenotype differences of Northwest Europe.

      So, yeah, I agree that the Ice Sheet is only part of the picture but it's not as you say either.

      Delete

Please, be reasonably respectful when making comments. I do not tolerate in particular sexism, racism nor homophobia. Personal attacks, manipulation and trolling are also very much unwelcome here.The author reserves the right to delete any abusive comment.

Preliminary comment moderation is... ON (sorry, too many trolls).