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Arctic melting and darkening

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Increasingly precise data on radiation reflected from the Arctic sea area. The Finnish Meteorological Institute has developed a new, globally unique method for estimating surface albedo in the Arctic sea area solely on the basis of microwave data.

Increasingly precise data on radiation reflected from the Arctic sea area

Its advantage over conventional optical methods is that neither clouds nor darkness interfere with measurements. The Finnish Meteorological Institute has developed a unique method for estimating surface albedo in the Arctic sea area. Arctic expert predicts final collapse of sea ice within four years. Prof Peter Wadhams calls for “urgent” consideration of new ideas to reduce global temperatures.

Arctic expert predicts final collapse of sea ice within four years

Photograph: John Mcconnico/AP One of the world's leading ice experts has predicted the final collapse of Arctic sea ice in summer months within four years. In what he calls a "global disaster" now unfolding in northern latitudes as the sea area that freezes and melts each year shrinks to its lowest extent ever recorded, Prof Peter Wadhams of Cambridge University calls for "urgent" consideration of new ideas to reduce global temperatures. In an email to the Guardian he says: "Climate change is no longer something we can aim to do something about in a few decades' time, and that we must not only urgently reduce CO2 emissions but must urgently examine other ways of slowing global warming, such as the various geoengineering ideas that have been put forward. " These include reflecting the sun's rays back into space, making clouds whiter and seeding the ocean with minerals to absorb more CO2.

Giant Antarctic glacier beyond point of no return, research says. Antarctica's Pine Island Glacier, one of the biggest single contributors to world sea-level rise, is melting irreversibly and could add as much as a centimetre (0.4 inches) to ocean levels in 20 years, a study said Sunday.

Giant Antarctic glacier beyond point of no return, research says

The glacier "has started a phase of self-sustained retreat and will irreversibly continue its decline," said Gael Durand, a glaciologist with France's Grenoble Alps University. Durand and an international team used three different models to forecast the glacier's future based on the "grounding line," which is the area under water where the ice shelf—a sea-floating extension of the continent-covering ice sheet—meets land. This line has receded by about 10 kilometres (six miles) in the past decade. The grounding line "is probably engaged in an unstable 40-km (25-mile) retreat," said the study, published in the journal Nature Climate Change. A massive river of ice, the glacier by itself is responsible for 20 percent of total ice loss from the West Antarctic Ice Sheet today. Arctic Warming is Altering Weather Patterns, Study Shows.

EDITOR'S NOTE: This story was originally published April 3.

Arctic Warming is Altering Weather Patterns, Study Shows

Given recent news that Arctic sea ice set a record low, it's a reminder that changes in the Arctic can affect the U.S. and Europe. North Pole Melting Leaves Small Lake At The Top Of The World. Arctic Sea Ice: What, Why and What Next. On September 19th, NSIDC, the National Snow and Ice Data Center, announced that Arctic sea ice has shrunk as far as it will shrink this summer, and that the ice is beginning to reform, expanding the floating ice cap that covers the North Pole and the seas around it.

Arctic Sea Ice: What, Why and What Next

The Arctic Sea Ice extent this September was far smaller than the previous record set in 2007. At 3.4 million square kilometers of ice coverage, this year’s Arctic minimum was 800,000 square kilometers smaller than the 2007 record. That difference between the previous record and this year’s is larger than the entire state of Texas. An ice-free summer in the Arctic, once projected to be more than a century away, now looks possible decades from now. North Pole melts, forms lake at top of the world.

If this image (above) doesn't scare you about the effects of global warming, you must have icewater in your veins.

North Pole melts, forms lake at top of the world

Yes, that's the North Pole. It's now a lake. NASA satellites see Arctic surface darkening faster. The retreat of sea ice in the Arctic Ocean is diminishing Earth's albedo, or reflectivity, by an amount considerably larger than previously estimated, according to a new study that uses data from instruments that fly aboard several NASA satellites.

NASA satellites see Arctic surface darkening faster

The study, conducted by researchers at Scripps Institution of Oceanography, at the University of California, San Diego, uses data from the Clouds and Earth's Radiant Energy System, or CERES, instrument. There are CERES instruments aboard NASA's Tropical Rainfall Measurement Mission, or TRMM, satellite, Terra, Aqua and NASA-NOAA's Suomi National Polar-orbiting Partnership (Suomi NPP) satellites.

The first CERES instrument was launched in December of 1997 aboard TRMM. As the sea ice melts, its white reflective surface is replaced by a relatively dark ocean surface. This diminishes the amount of sunlight being reflected back to space, causing Earth to absorb an increasing amount of solar energy.