Scientists Excited by Arctic Ocean Ridge Volcanoes

National Geographic News November 29, 2001 (extract)

The floor of the Arctic Ocean is one of the last frontiers on Earth, and mapping it was thought to be an impossible task-too much ice, too remote, too difficult...But on its inaugural research expedition, the U.S. Coast Guard Cutter Healy, a specially designed icebreaker equipped for science, has returned with highly detailed maps, exotic life forms, and new discoveries of volcanic activity below the ice cap... "We have completely unexpected results," said Langmuir. "The ocean ridge below the Arctic is completely unique. We found 12 new volcanoes where we expected to find none, and we found unexpected and abundant hydrothermal activity."

The Gakkel Ridge

The Arctic expedition, funded by the National Science Foundation, focused on the northern end of the mid-ocean ridge. The ridge is a volcanically active mountain range, 52,000 miles long, that runs beneath the North and South Atlantic Oceans, the Arctic Ocean, the Indian Ocean, and the South Pacific. Ocean ridges are like great gashes in the Earth, where hot rock from the Earth's core is forced up.

The Gakkel Ridge is the deepest and most remote portion of the global mid-ocean ridge system. It extends 1,100 miles from north of Greenland to Siberia, lying about three miles beneath the Arctic ice cap. The theory is that volcanic eruptions beneath the ocean create new oceanic crust, which then moves away from the ridge. This process, known as seafloor spreading, is thought to underlie the movement of continents. Unlike volcanoes on land, which are tall and conical in shape, undersea volcanoes are long, linear, and oozing.

The Gakkel Ridge is the slowest spreading ridge in the world, spreading at a rate of one centimeter (less than half an inch) a year. Ridges in other parts of the mid-ocean range spread up to 18 centimeters (7 inches) a year. Because it is so slow-spreading, scientists expected there would be very little volcanic activity along the Gakkel Ridge...Unexpectedly, the AMORE expedition found an abundance of both volcanism and hydrothermal activity.

An international team of researchers...(has found)...layers of volcanic ash on the seafloor, which indicates a gigantic volcanic eruption. Explosive volcanic eruptions on land are nothing unusual and pose a great threat for whole areas...These are the first pyroclastic deposits we've ever found in such deep water, at oppressive pressures that inhibit the formation of steam, and many people thought this was not possible...The Gakkel Ridge in the Arctic Ocean spreads so slowly at 6-14 mm/year, that current theories considered volcanism unlikely - until a series of 300 strong earthquakes over a period of eight months indicated an eruption at 85� N 85� E in 4 kilometres water depth in 1999.

The simple fact is scientists just don't know a lotof things and need to stop being treated like holy men with the only "truth." Science is not about truth, faith, or consensus, it's about verifiable facts in the real world.

In 2008 global warming activists are crying the Arctic ice is melting because of man-made global warming, while forgetting the fact the Antarctic ice is growing. Global warming critics would be quick to claim the heat of these volcanoes is melting the ice; that is not possible by itself.

Since the 1970s NASA has reported an increase in solar radiation, which will warm the oceans. This slightly warmer water will out-gas CO2 (same thing as an open bottle of soda on a warm day), but is counter-balanced by more cloud formation that reflects sunlight, thus producing a negative feedback to prevent runaway global warming.

But this slightly warmer water, combined with these massive volcanic eruptions altering the ocean floor, would change the current flows of the warmer (non man-made) Pacific and Atlantic currents from the south.

This would account for the "underside melting" they have noted in the articles below. The changing pattern of sea ice itself will alter heat flow as less ice and open water will absorb more sunlight, unlike ice, which is more reflective.

Under the Arctic Ice, a Seabed Yields Some Fiery Secrets

July 1, 2003 New York Times Company (extract)

Deep beneath the ice-sheathed Arctic Ocean, a 1,000-mile seam in the earth's rocky crust, long thought to be largely dormant, has been revealed as a simmering necklace of volcanoes and hot-water vents that may harbor unique life forms. Earlier surveys in the depths near the North Pole had identified a couple of seabed volcanoes in one place along the seam, which is called the Gakkel Ridge...Researchers and experts not directly involved in the new work said the findings challenged longstanding notions about such midocean ridges, which are the geologic factories forging earth's ever-changing crust...

The researchers said they were shocked when more than 80 percent of the instrument deployments detected such emissions over the 600-mile portion of the ridge that was surveyed. "We were expecting it to be practically dead...Instead we got so many readings that we thought the equipment was not working right."

By chance, that summer the polar ice pack was exceptionally thin and widely dispersed, so the ships -- the American Coast Guard vessel Healy and the German Polarstern -- were able to collect far more data than had been expected...Some of the volcanic domes that the survey detected rise more than a mile from the three-mile-deep bottom of the rift valley running down the center of the Gakkel Ridge. The hot spots found along the ridge appear to have existed fairly consistently for up to 25 million years in some cases...

Volcanic eruptions reshape Arctic ocean floor

June 26, 2008 Agen�e France-Presse: Reconstruction of the Gakkel Ridge beneath the Arctic ocean, where a valley filled with flat-topped volcanos up to 2 km wide and hundreds of metres high has been found...The eruptions - as big as the one that buried Pompei - took place in 1999 along the Gakkel Ridge, an underwater mountain chain snaking 1,800 km from the northern tip of Greenland to Siberia...Both sonar and visual images showed an ocean valley filled with flat-topped volcanos up to 2 km wide and several hundred metres high.

Monday, August 04, 2008

Ice melt may open Northwest Passage for a second year. Scientists expet end-of-summer Arctic ice pack to be close to its lowest measurement on record

Alaska's warm weather this summer has all "gone north." Way north. Scientists at the National Snow and Ice Data Center say strong, southerly winds from the North Slope have devoured a huge swath of Arctic ice larger than the state of Texas in the heart of the Beaufort Sea. Combining that loss with the overall decline in sea ice in recent years should leave this year's end-of-summer Arctic ice pack close to its lowest measurement on record...Daily satellite images relayed to the NSIDC headquarters in Boulder, Colo., also indicate the Northwest Passage is ice-free as far east of Alaska as Amundsen Gulf, about 600 miles east of the Alaska-Canada border...

Ice in the Arctic historically melts each summer until the middle of September. From 1996 to 2005, that summer minimum fell from a total of about 3 million to 2.1 million square miles of ice...Comprehensive satellite monitoring of the Arctic has been available only since 1979, but the dramatic decline in the extent and thickness of the ice since then has prompted most climate scientists to conclude that "it's clearly a global warming signal."

Offsetting the ice loss north of Alaska this summer is a large accumulation of new first-year ice off the north coast of Russia. NSIDC forecasters say it's hard to know whether it will melt or stay. If the latter occurs, Serreze said, then 2008 will probably go down as a close second to last year's record Arctic ice minimum.

On July 31, the extent of sea ice in the Arctic stood at 2.98 million square miles - about 400,000 square miles less than the 1979 to 2000 average for the same date, according to data posted on the NSIDC Web site. But it was about 35,000 square miles more than the July 31 measurement during last year's record summer.

In other words, it's not looking like it's going to break last year's record (minimum), but we're well below normal. It should be No. 2." A wild card this year is the overall thinness of the ice - even near the North Pole. In April NSIDC scientists suggested that the ice at the pole might temporarily disappear this summer for the first time on record.

Now it doesn't appear that it will...The old multi-year ice this year is thinner than researchers expected, possibly because its underside is melting faster than it used to, or because south-flowing currents are flushing some of the ice into the Atlantic, according to an analysis posted on the NSIDC Web site. But the first-year ice is slightly thicker than expected, possibly because a lack of insulating snow cover last winter failed to protect it from the effect of deep freezing. In any event, the North Pole is still covered in ice.

Ref http://www.juneauempire.com/stories/080408/sta_313372460.shtml


 





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