CanWest, Reuters, etc: Canada’s boulders say Ice Age’s last big blast triggered by meltwater surging into Arctic, not North Atlantic.
For a long time climatologists have argued convincingly that, as the last ice age neared its end, an initially puzzling resurgence some 13,000 years ago called the Younger Dryas probably resulted from fresh water pouring out of N. America’s huge ice sheet in a giant flood. It plugged warm ocean currents. The more northern latitudes re-froze for a millennium or so. Most of the researchers on the case supposed those waters poured through what is today the Gulf of St. Lawrence in southeast Canada.
In Nature today comes argument that the bulk of the waters instead ran almost due north along the west margin of the shrunken Laurentide ice mass. They filled what we now call the McKenzie River drainage, debouching via its delta jutting into the Arctic Ocean. Huge boulders in sediments along the route say so. Same basic argument on the climate’s flip-flop, different locale for the hinge.
I’d like to have seen something putting the news into context with other megafloods of the deep past – the ones that scoured the English Channel, that carved the scablands of Washington State, that filled the dried Mediterranean, and so on. But, one suspects, editors weren’t calling for long articles on this.
Odd that this interesting and lengthy report in Nature gets no feature treatment in the journal’s advance notice to reporters – merely linked under the catchall list of things also in the magazine this week. But two UK and one Canadian university issued press releases.
Stories:
- CanWest – Margaret Munro: Scientists uncover paths of massive flood / It altered ocean currents; Resulting cold snap lasted 1000 years ;
- Reuters – David Fogarty : Mega-flood triggered cooling 13,000 years ago: scientists ; The story, not very long, has the essentials but is vague in its lede and hed that the news is not the flood, but where it ran into the sea.
- Treehugger – Matthew McDermott: Route of 13,000 Year Old Mini Ice Age Inducting Mega-Flood Determined : Pretty small and specialized news outlet here, and worth a salute for the accuracy of its hed and, more important, for putting this into context with other recent news on fresh water, the North Atlantic, and regional climate change.
- Nature News – Quirin Schiermeier, Richard Monastersky: River reveals chilling tracks of ancient flood ;
Grist for the Mill:
University of Sussex Press Release ; University of Sheffield Press Release ; University of Manitoba Press Release ;
- Charlie Petit
