Saturday, September 06, 2014

Reshaping the Earth


Fascinating article about sea level increases and the vulnerability of the Sea Floor. This information mirrors the prophecies of the Freedom Star World Map - especially Iceland. - Lori

[by Carolyn Kormann for the New Yorker]
In the tenth century, a Norseman named Bárður Bjarnason settled in northern Iceland with his nine sons. Conditions were rough, and Bjarnason decided to follow his sons south in search of more fertile land. His route, the story goes, stretched across Europe’s largest ice cap, Vatnajökull, and passed by several volcanoes, including one that he decided to name after himself. Blanketed in white, it probably looked much like it does today—a massive, radiant hump. Bjarnason, or one of his descendants, called the volcano Bárðarbunga. The name means “Bárður’s bulge.”
Over the weekend, Bárður’s bulge started to erupt. A glowing wall of molten rock is now leaping and streaming from a fissure north of the volcano’s ice cap. It’s a “nicely behaved” eruption, as one scientist put it—a “nice fire curtain with lava squirting out”—following a few nerve-wracking weeks of “seismic crisis,” marked by thousands of subglacial earthquakes and a threatening intrusion of magma. An eruption could still explode through the volcano’s glacier. Major floods of ice melt would follow, as well as a giant ash cloud, perhaps similar to the one in 2010 from Eyjafjallajökull, which shut down European air space for a week and left millions of travellers stranded around the world. Earthquakes continue to rattle Bárðarbunga’s caldera. Lava is flowing north of the glacier at about a hundred cubic metres per second, and a dramatic white plume of steam and gas rises to four and a half kilometers above the sea.

Meanwhile, the attention on Bárður’s bulge has prompted a discussion of the relationship between volcanoes, melting glaciers, and climate change. As a glacier recedes, its enormous mass is removed from the land. Relieved of that load, the land rebounds slightly and the pressure underground is reduced, enabling more magma to accumulate; eventually, some of that magma will rise and erupt through the Earth’s surface. In other words, global warming could alter the shape of the planet. “If you deglaciate Iceland, volcanism in Iceland should increase,” Jerry Mitrovica, a professor of geophysics at Harvard, said. “We’re moving the hand from the door and allowing the door to swing open.”
No one is suggesting that climate change is causing Bárðarbunga, in particular, to erupt; the ways in which atmospheric changes might affect geophysical events of this kind are hard to isolate on anything close to a human time frame. “It can be very difficult to decide if changes in the rate of earthquakes or volcanoes have actually happened,” Duncan Agnew, a geophysicist at the Scripps Institution of Oceanography, wrote in an e-mail. “It’s a statistical question, so one event isn’t enough—you need to have a long prior history to compare it with.”
Iceland’s geological record offers some insights. The nation’s volcanoes sit directly over a hot spot on the Mid-Atlantic Ridge, and have been depositing new layers of rock for millions of years. Scientists who have analyzed these layers have found that, beginning about ten thousand years ago, after the last ice age’s glaciers began to melt, Iceland’s volcanoes started erupting as much as fifty times more frequently. Lava flowed freely and ash fell abundantly for the next two thousand years. Read More