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Posts Tagged ‘Arctic Ocean’

2011: Headed for Record Arctic Melt?

July 21, 2011 Comments off

ouramazingplanet

arctic-sea-ice-satellite-110720.jpgJuly 11, 2011: Arctic sea ice, seen by satellite. Credit: NASA.

This year could be well on its way toward earning a dubious spot in the record books.

Arctic sea ice has melted away with astonishing speed in the first half of July, at an average rate of about 46,000 square miles (120,000 square kilometers) per day, according to the National Snow and Ice Data Center (NSIDC) in Boulder, Colo.

That’s equivalent to an area roughly the size of Pennsylvania melting into the sea every 24 hours.

“That’s relatively fast,” said Julienne Stroeve, a research scientist at the NSIDC.

Already, sea ice extent — how far ice extends across the ocean — this year is below the extent for the same time in 2007, a year which, in September, saw the lowest sea ice coverage ever recorded.

As of July 17 this year, sea ice covered 2.92 million square miles (7.56 million square kilometers) of the frigid Arctic Ocean. That may sound like a lot, but it’s 865,000 square miles (2.24 million square kilometers) below the 1979 to 2000 average.

However, Stroeve said, much of what Read more…

Doomsday fire: Millions of volcanoes are stirring beneath the world’s oceans

May 11, 2011 Comments off

theextinctionprotocol

In 1993, marine geophysicists aboard the research vessel Melville discovered 1,133 previously unmapped underwater volcanoes off the coast of Easter Island. Though some of the newly discovered volcanoes rose as much as one-and-a-half miles above the seafloor, their summits still remained half a mile below the water’s surface- all this in a comparatively small area of only 55,000 square miles, about the size of New York State. The geophysicists had increased the known supply of underwater volcanoes by more than ten percent just in a matter of months. That was 1993. Today, scientists estimate that there are more than three million underwater volcanoes. That’s a three followed by six zeroes! In 2007, oceanographers Hillier and Watts surveyed 201,055 submarine volcanoes. “From this they concluded an astounding total of 3,477,403 submarine volcanoes must reasonably exist worldwide,” said this article by John O’Sullivan. Hillier and Watts “based this finding on the earlier and well-respected observations of Earth and Planetary Sciences specialist, Batiza (1982) who found that at least 4 per cent of seamounts are active volcanoes.” According to Batiza’s survey, the Pacific mid-plate alone contains an incredible 22,000 to 55,000 underwater volcanoes, with at least 2,000 of them considered active. Thinking Read more…

New report confirms Arctic melt accelerating

May 3, 2011 Comments off

ap.org

FILE - In this July 19, 2007 file photo an iceberg is seen off Ammassalik Island in Eastern Greenland. A new assessment of climate change in the Arctic shows the ice in the region is melting faster than previously thought and sharply raises projections of global sea level rise this century. (AP Photo/John McConnico, File)

STOCKHOLM (AP) — Arctic ice is melting faster than expected and could raise the average global sea level by as much as five feet this century, an authoritative new report suggests.

The study by the international Arctic Monitoring and Assessment Program, or AMAP, is one of the most comprehensive updates on climate change in the Arctic, and builds on a similar assessment in 2005.

The full report will be delivered to foreign ministers of the eight Arctic nations next week, but an executive summary including the key findings was obtained by The Associated Press on Tuesday.

It says that Arctic temperatures in the past six years were the highest since measurements began in 1880, and that feedback mechanisms believed to accelerate warming in the climate system have now started kicking in.

One mechanism involves the ocean absorbing more heat when it’s not covered by ice, which reflects the sun’s energy. That effect has been anticipated by scientists “but clear evidence for it has only been observed in the Arctic in the past five years,” AMAP said.

The report also shatters some of the forecasts made in 2007 by the U.N.’s expert panel on climate change.

The cover of sea ice on the Arctic Ocean, for example, is shrinking faster than Read more…

Large-Scale Assessment Of The Arctic Ocean: Significant Increase In Freshwater Content Since 1990s

March 28, 2011 Comments off

nanopatentsandinnovations

The freshwater content of the upper Arctic Ocean has increased by about 20 percent since the 1990s. This corresponds to a rise of approx. 8,400 cubic kilometres and has the same magnitude as the volume of freshwater annually exported on average from this marine region in liquid or frozen form. This result is published by researchers of the Alfred Wegener Institute in the journal Deep-Sea Research. The freshwater content in the layer of the Arctic Ocean near the surface controls whether heat from the ocean is emitted into the atmosphere or to ice. In addition, it has an impact on global ocean circulation.

Differences in the mean salinity of the Arctic Ocean above the 34 isohaline between 2006 to 2008 and 1992 to 1999.

Negative values are shown in yellow, green, and blue and stand for an increase of freshwater.

Image: Benjamin Rabe, Alfred Wegener Institute Read more…