Climate flickering ended last ice age

[wolram]

http://www.sciencedaily.com/releases/2009/02/090216092824.htm

Quote.
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.

[Andre]

Nice find Wolram,

It has been presented last year in Oslo during the International Geologic Congress (http://www.cprm.gov.br/33IGC/1358385.html). A bit curious habit of this kind of researching is careful examination of the local evidence but then followed by wild speculations disdaining anything else that happened in the world. For instance, how could you possibly explain the anoxic oxic/oscillations in the Santa Barbara Basin California (http://www.cosis.net/abstracts/EGU2007/03110/EGU2007-J-03110.pdf?PHPSESSID=1a580be6a5656ad22f481c95837dc4 6b) or in the Caracio basin (http://www-odp.tamu.edu/publications/165_SR/chap_04/c4_4.htm) Venezuela with some melting glaciers in Norway?

[Mammo]

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.

[Andre]

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 (http://www.nature.com/ngeo/journal/v1/n8/abs/ngeo263.html) 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.

[Mammo]

Does it with 30,000 years in between?
It could take 30,000 years to reach it's maximum increase in obliquity, and then oscillate on a smaller scale until stabilization.

[Evo]

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.

[Mammo]

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.

[wolram]

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.

[Mammo]

http://www.sciencedaily.com/releases/2009/02/090216092824.htm
[QUOTE]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.
The evidence of a micrometeorite bombardment (Firestone et al) around 12.9 ka is presumably a candidate for this fluctuating climate change.