"The Younger Dryas Boundary strewnfield (after Wittke et al 2013, and Kennett et.al 2014). The area enclosed within the red boundary defines the current known limits of the YDB field of cosmic-impact proxies spanning 50 million square kilometers."
It seems that, if a CME, it hit North America, melting the Laurentide Ice sheet with some of the energy clipping Greenland and energy stretching across the Atlantic to Western Europe and a patch hitting the Eastern shore of the Mediterranean....flash burning areas that weren't under ice leaving the "black mat" layer.
We also know that the Vikings had settled and farmed Southern Greenland so there was a time when much of it was free of glacial ice. That would eliminate any evidence that ice core samples would find of melt/refreeze. ["The culture of the Norsemen was at its highest point around 1200 A.D. An estimated 2,500 people lived in Greenland at this time. Trading with Europe was prolific, and the Norsemen received requests for luxury items like walrus teeth, which they would travel far, along the shores of Greenland, to obtain.Climate changes and the beginning of the Little Ice Age forced the Norsemen at the start of 13th century A.D., to consolidate and move everyone to the South of Greenland, where farming was still possible in spite of cold summers and longer winters. Some of the best kept ruins of farm buildings are actually found in the fiord by the capital city of Nuuk, on the west coast, and testifies to the fact, that they moved away due to climate change and hardship, and during a time when the farms in Southern Greenland were significantly larger, but fewer in number." visitgreenland.com ]
grahamhancock.com The article was written with a cometary disintegration in the upper atmosphere in mind before the notion bubbled up that a CME is a more likely cause.
But so far, the evidence for a periodic CME hitting Earth approximately every 12,000 years is rapidly losing ground in my opinion.
The main concerns remain the Grand Solar Minimum, weakening magnetosphere/magnetic pole shift/grid failure, volcanoes and EQs (New Madrid Seismic Zone and/or Cascadia Subduction Zone for North America). |
