His conclusions were that global warming has caused volcanic eruptions and earthquakes in the ancient past.
He went on to say that the anthropogenic global warming occurring now will do so too.
Over two and a half years ago he mentioned by name the very volcano that just erupted in Iceland shutting down air traffic over Europe.
He also indicated that earthquakes could result from anthropogenic global warming:
"In places like Iceland, for example, where you have the Eyjafjallajökull ice sheet, which wouldn't survive [global warming], and you've got lots of volcanoes under that, the unloading effect can trigger eruptions," McGuire said.(Live Science, 2007, emphasis added). A paper recently published in the journal Arctic indicates that in fact the ice sheets have been melting and vanishing:
With the changing dynamics in the crust, faults could also be destabilized, which could bring a whole host of other problems.
"It's not just the volcanoes. Obviously if you load and unload active faults, then you're liable to trigger earthquakes," McGuire told LiveScience, noting that there is ample evidence for this association in past climate change events.
Close to 50 years of data show the Devon Island ice cap, one of the largest ice masses in the Canadian High Arctic, is thinning and shrinking.(Science Daily). We all know that there is volcanic activity exactly where he said some would be, and there have been many earthquakes over the past several months.
A paper published in the March edition of Arctic, the journal of the University of Calgary's Arctic Institute of North America, reports that between 1961 and 1985, the ice cap grew in some years and shrank in others, resulting in an overall loss of mass. But that changed 1985 when scientists began to see a steady decline in ice volume and area each year.
"We've been seeing more mass loss since 1985," says Sarah Boon, lead author on the paper and a Geography Professor at the University of Lethbridge. The reason for the change? Warmer summers.
It behooves scientists to rethink these possibilities, because it can cause severe economic impact, and perhaps tempt one nation to attack another because they know the other side's military aircraft are grounded.
Ice Sheet melt is not the end of the story:
McGuire conducted a study that was published in the journal Nature in 1997 that looked at the connection between the change in the rate of sea level rise and volcanic activity in the Mediterranean for the past 80,000 years and found that when sea level rose quickly, more volcanic eruptions occurred, increasing by a whopping 300 percent.(ibid, Live Science, link above). In other words as the melting ice around the world is released into the atmosphere, causing climate change, it will eventually find its way to the oceans where weight on the crust will be redistributed causing different stresses than usual on the tectonic plates.
Which means more "surprises".
Some major networks are carrying the story that global warming causes or can cause volcanic activity in some circumstances: Warming Could Wake Up Volcanos (MSNBC), Global Warming May Trigger More Volcanoes (Telegraph, UK). If you know of any more, feel free to post a comment.