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The impact hypothesis (11), once declared dead (12, 13), recently gained new support from the discovery of siliceous scoria-like objects (SLOs) with global distribution, which provide strong evidence for processing at high temperatures and pressures consistent with a cosmic impact (14)….
…Until the question about the nature of Pt-rich material and the means of its delivery to the ice is resolved, an extraterrestrial source of Pt appears likely…..
Sarcasm aside, we have a profound development here from Harvard. An enlightening team from that fabled university has provided arguably the best independent evidence yet that something very powerful — from space — went down ~12,876 years ago which dramatically changed climate, led to the elimination of 35 or so genera, and altered our course forever.
In the finest spirit of Thomas Kuhn their work is the best public indication so far that the paradigm is cracking and the paleo-worm is turning.
A convenient aspect of the YDB hypothesis is that the evidence is at hand for most earth science researchers with the curiosity, equipment and skill to contribute. These gentleman did so and they will be rewarded in years to come with deserved accolades. But most important for the propagation of our understanding was their work with — they term it encouragement from — Dr. Wallace “Wally” Broecker of Columbia University.
Wally Broecker is the kind of guy you pick first for your team in the science fair. And if he ain’t available, you wait hopeful that he will someday join.
Broecker originally authored the Thermohaline Circulation Shutdown theory in the early 1970’s and many call him the father — or grandfather — of climate science itself. Having devoted that much time to defining the Younger Dryas it should be no surprise that he is slow to come around to a cosmic impact as the cause (what’cha bet he never considered it prior to 2007?).
And indeed there is no confirmation that Wally agrees that a disintegrating comet induced his cold time. But “encouraging” a look for evidence — finding it — and lending his name to the credits is certainly reason to rejoice.
(I should add that Jim Kennett, the grise eminence of the YDB team, is a peer of Broecker’s and they have a long, long history of fruitful collaboration. That’s even more reason for hope that we will get a fair shake from here out from granddad.)
As far as the substance of the paper is concerned, what thrills me most is the match of the platinum spike with the YD initiation. If you are too far off in this game you are cave bear meat.