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Less Ice In Arctic Ocean 6000-7000 Years Ago

April 9, 2019
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By Paul Homewood

 

 

This paper is ten years old, but is still highly relevant:

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Recent mapping of a number of raised beach ridges on the north coast of Greenland suggests that the ice cover in the Arctic Ocean was greatly reduced some 6000-7000 years ago. The Arctic Ocean may have been periodically ice free.

”The climate in the northern regions has never been milder since the last Ice Age than it was about 6000-7000 years ago. We still don’t know whether the Arctic Ocean was completely ice free, but there was more open water in the area north of Greenland than there is today,” says Astrid Lyså, a geologist and researcher at the Geological Survey of Norway (NGU).

Shore features

Together with her NGU colleague, Eiliv Larsen, she has worked on the north coast of Greenland with a group of scientists from the University of Copenhagen, mapping sea-level changes and studying a number of shore features. She has also collected samples of driftwood that originated from Siberia or Alaska and had these dated, and has collected shells and microfossils from shore sediments.

”The architecture of a sandy shore depends partly on whether wave activity or pack ice has influenced its formation. Beach ridges, which are generally distinct, very long, broad features running parallel to the shoreline, form when there is wave activity and occasional storms. This requires periodically open water,” Astrid Lyså explains.

Pack-ice ridges which form when drift ice is pressed onto the seashore piling up shore sediments that lie in its path, have a completely different character. They are generally shorter, narrower and more irregular in shape.

Open sea

”The beach ridges which we have had dated to about 6000-7000 years ago were shaped by wave activity,” says Astrid Lyså. They are located at the mouth of Independence Fjord in North Greenland, on an open, flat plain facing directly onto the Arctic Ocean. Today, drift ice forms a continuous cover from the land here.

Astrid Lyså says that such old beach formations require that the sea all the way to the North Pole was periodically ice free for a long time.

”This stands in sharp contrast to the present-day situation where only ridges piled up by pack ice are being formed,” she says.

However, the scientists are very careful about drawing parallels with the present-day trend in the Arctic Ocean where the cover of sea ice seems to be decreasing.

"Changes that took place 6000-7000 years ago were controlled by other climatic forces than those which seem to dominate today,” Astrid Lyså believes.

Inuit immigration

The mapping at 82 degrees North took place in summer 2007 as part of the LongTerm project, a sub-project of the major International Polar Year project, SciencePub. The scientists also studied ruined settlements dating from the first Inuit immigration to these desolate coasts.

The first people from Alaska and Canada, called the Independence I Culture, travelled north-east as far as they could go on land as long ago as 4000-4500 years ago. The scientists have found out that drift ice had formed on the sea again in this period, which was essential for the Inuit in connection with their hunting. No beach ridges have been formed since then.

”Seals and driftwood were absolutely vital if they were to survive. They needed seals for food and clothing, and driftwood for fuel when the temperature crept towards minus 50 degrees. For us, it is inconceivable and extremely impressive,” says Eiliv Larsen, the NGU scientist and geologist.

https://www.sciencedaily.com/releases/2008/10/081020095850.htm

 

 

These findings fit in with many other studies, which confirm that the Arctic was much warmer than now up to around 3000 BC.

Regardless of the causes of this earlier warmth, it makes a nonsense of claims about “tipping points”, “methane release” and “melting permafrost” scares.

15 Comments
  1. Tom O permalink
    April 9, 2019 7:58 pm

    There is a certain sadness felt when you realize that scientists are not able to actually state reality. That is, it would be career ending for them to have not made a point about climate forces back then being different than they are now. The obvious response to such a statement would be “and how do you know that? How do you know that the forces at work then are not at work now as well?” It is sad that they can not answer that question, but have to side step it in order to have a job when, in reality, they shouldn’t have a job if they can’t answer that question honestly. Morality and ethics apparently died at the same time as did common sense.

  2. Charles Wardrop permalink
    April 9, 2019 10:59 pm

    Like other, disparate political issues, common sense and probity have been shed by people in important places, so corruption must play a part, especially with so much money, from taxpayers, to be got.Groupthink shares the blame.
    Science is corrupted, e.g., by Gore’s “settled science,” a very sad development.
    The rational answer is to withold funds, as all the work now posdible has been completed, and play a waiting game.
    Pres. Trump is right in this field!

  3. April 9, 2019 11:01 pm

    Further back:
    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2694912/
    Ancient Biomolecules from Deep Ice Cores Reveal a Forested Southern Greenland

    “We show that high altitude southern Greenland, currently lying below more than two kilometers of ice, was once inhabited by a diverse array of conifer trees and insects that may date back more than 450 thousand years. The results provide the first direct evidence in support of a forested southern Greenland and suggest that many deep ice cores may contain genetic records of paleoenvironments in their basal sections.”

    Recent again, agreeing with the Norwegian study above:
    https://web.archive.org/web/20010222053802/http://carc.org/pubs/v15no5/5.htm

    Robert McGhee, former Head of the Scientific Section, Archaeological Survey of Canada:

    “By about 7000 years ago the massive glaciers of the last Ice Age had retreated to the mountain peaks of the eastern Canadian Arctic. Tundra vegetation had become established, and was grazed by caribou, musk oxen, and, in some areas, by bison. The gulfs and channels between the arctic islands had long been at least seasonally ice-free, and provided a home to populations of seals, walrus, and whales.

    There is considerable evidence that for the next 3500 years the arctic climate was noticeably warmer than today, the tree-line was north of its present position, sea ice was less extensive, and animal populations were large and well established.”

    During the Medieval Warm Period, normal summer conditions were probably similar to those which occur in occasional warm and ice-free summers at the present time. Such pleasant summers began to occur less frequently after about AD 120O, and were extremely rare during the ensuing Little Ice Age. As the deteriorating climate decreased the viability of the already marginal Norse farming in Greenland and increased ice in the North Atlantic interfered with navigation to Europe, the Norse colonies declined, and finally died out some time around AD 1500. “

    • April 10, 2019 12:04 pm

      Pollen and spores are extremely stable. They have been used to map the glacial advances and retreats in cores from bogs and lakes.

  4. April 9, 2019 11:08 pm

    Isn’t it believed that global sea level were also a good bit higher at roughly the same time?

  5. Phoenix44 permalink
    April 10, 2019 8:46 am

    It really is sad when scientists are forever into circular reasoning. If sea ice decline happened before regardless of CO2 then it is obvious it could happen again. So now we don’t need CO2 to cause temperature increases and so that debunks the whole claim that it can ONLY be CO2.

  6. Doug Shield permalink
    April 10, 2019 10:04 am

    There’s a simple explanation for the lack of ice 7000 years ago…….people driving SUVs and shooting off on long-haul air flights!

  7. Adrian permalink
    April 10, 2019 11:52 am

    Paul, yes I am ignoring your holiday as you appear to be as well, did these evidences make it into peer-reviewed journal?

  8. April 10, 2019 5:47 pm

    This ties in with the Sahara changing to be a desert around 5000 years ago:

    “What is now the Sahara Desert was the home to hunter-gatherers who made their living off the animals and plants that lived in the region’s savannahs and wooded grasslands 5,000 to 11,000 years ago.”

    https://phys.org/news/2017-01-green-sahara-ancient-rainfall-regime.html

    Though naturally “scientists” have a laughable explanation: the people became farmers, which instantly made them evil, and the animals ate all the grass!

    • April 10, 2019 8:04 pm

      Ha, irony is impossible, any daft suggestion will already have been studied, especially if colonialism was involved:

      “Typically, traditional subsistence pastoralism has been seen as agents of environmental degradation through overgrazing, habitat change and resource competition with wildlife. This view (Fig. 1a) was embedded in the environmental doctrine of the twentieth century, partly as a consequence of the historical relationship between colonial administrators and traditional pastoralists1. This doctrine has led to a recent suggestion that early pastoralism was so unsustainable that it triggered a climatic deterioration in the Sahara around 5500 years ago (at the end of the African Humid Period).”

      https://co2coalition.org/2018/10/01/pastoralism-may-have-delayed-the-end-of-the-green-sahara/

  9. April 11, 2019 4:06 am

    Reblogged this on Climate Collections.

  10. avro607 permalink
    April 11, 2019 7:52 pm

    With ref. to Sahara,apparently the weather patterns changed,and it stopped raining.Other hypotheses have included aslight wobble of the earth,s axis,or cold water floodimg into the North Atlantic from an ice dam breakage in North America.See deserts on the same parallel.Sorry,my refs on this chg. in climate are lost.

  11. April 14, 2019 10:24 pm

    Maybe I commented on this before, but a study of reports by 19th century Arctic explorers showed conditions 150 years ago were similar to today.
    The study is https://seagrant.uaf.edu/nosb/2005/resources/arctic-explorers.pdf
    My synopsis is https://rclutz.wordpress.com/2016/11/27/todays-arctic-compares-with-150-years-ago/

    • dave permalink
      April 15, 2019 8:46 am

      Late snow on the Greenland ice-sheet means that the accumulation is now approaching “normal.”

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