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Climate flickering ended last ice age

  1. Feb 18, 2009 #1


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    The Younger Dryas event, which began approximately 12,900 years ago, was a period of rapid cooling in the Northern Hemisphere, driven by large-scale reorganizations of patterns of atmospheric and oceanic circulation. Environmental changes during this period have been documented by both proxy-based reconstructions from sediment archives and model simulations, but there is currently no consensus on the exact mechanisms of onset, stabilization, or termination of the Younger Dryas. In contrast to existing knowledge, the Nature article shows that the climate shifted repeatedly from cold and dry to wet and less cold, from decade to decade, before interglacial conditions were finally reached and the climate system became more stable.
  2. jcsd
  3. Feb 20, 2009 #2
  4. Feb 20, 2009 #3
    Yeah, great article Wolram.

    Very interesting argument Andre. Very enlightening. Sorry to go on, but the 'large body close encounter' of a giant comet like near-miss with the Earth around 40,000 years ago we discussed earlier fits the bill. The tilt would have increased and then oscillated before settling into the Earth's obliquity cycle we are now familiar with. I'm surprised myself to see how it seems to fit all the criteria so effortlessly.
  5. Feb 20, 2009 #4
    Does it with 30,000 years in between?

    Moreover there is something fishy with that article. It suggests that the transition to the YD in the Meerfelder maar varves was around 12,870 varve count years ago. However here it is 12,700 years, which is quite robust, as being 200 varve years before the mega eruption of the Laacher see maar around 12,920 years ago.
  6. Feb 20, 2009 #5
    It could take 30,000 years to reach it's maximum increase in obliquity, and then oscillate on a smaller scale until stabilization.
  7. Feb 20, 2009 #6


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    Mammo, overly speculative posts are not allowed here. Do you have any peer reviewed papers on such an incident? I have found nothing in my searches that even suggests such a thing.
  8. Feb 20, 2009 #7
    I do seem to have got a bit carried away with myself Evo. I doubt whether there's a paper on the idea, I admit. I'm interested in other people's explanations of the fluctuations, it's a fascinating topic.
  9. Feb 20, 2009 #8


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    You guys will have to bicker amongst yourselves, i find there is is no truths in these things, may be we will never know, but i hope for enlightenment, but now i am fizzled out.
  10. Feb 21, 2009 #9
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