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That's already been observed

Anyway, a new analysis out of the University of Southampton, in the U.K., points out that this cooling actually makes the upper atmosphere contract, removing some of the friction that eventually drags space junk back to Earth (and yes, believe it or not, there's a tiny bit of air in low-earth orbit, where the space junk problem is most acute). With less falling to Earth, there's more to slam into working satellites, the International Space Station and whatever else happens to be up there.

Still, the collapse of the thermosphere was bigger than the sun's activity alone can explain. Emmert suggests that the increasing amounts of carbon dioxide making its way into the upper atmosphere might have played a role in the anomaly.

Carbon dioxide acts as a coolant in the upper atmosphere, unlike in the lower atmosphere, shedding heat via infrared radiation. As carbon dioxide levels build up on Earth, it makes its way into the upper levels and magnifies the cooling action of the solar minimum, Emmert said. As carbon dioxide gradually builds up, "we expect every solar minimum to be a little lower, and then this solar minimum comes along, but instead it's a lot lower. And that's pretty surprising," said Stanley Solomon, a senior scientist with the National Center for Atmospheric Research who wasn't directly involved in this research.

But, Emmert said, even taking into account the solar activity and carbon dioxide buildup doesn't fully account for this abnormal collapse. Despite the puzzling anomaly, the collapse of the thermosphere is unlikely to have a direct effect on our daily lives, said Solomon. "It's not going to affect the weather, or you won't be able to tell that this is going on by looking at the sky. It's not going to look any darker," he said.

But the contraction of the thermosphere can affect the drag on satellites and space junk orbiting at those levels. "Debris that's up there stays up longer. The amount of orbital debris is a concern for space navigation. There is concern that space debris is building up," Emmert said. The abnormal change in the thermosphere may also affect other layers of the atmosphere, and though less certain, can result in slight disruptions of satellite communications, including global-positioning system signals, Solomon said. Emmert said there were still other possibilities unaccounted for that could have contributed to this phenomenon.

"It could be that we're underestimating the effects [of carbon dioxide] somehow. It could be because there were some physics that we're missing in the region of the atmosphere below the thermosphere, which quickly affects the thermosphere," he said. The researchers say they will continue to monitor the upper atmosphere, which is already rebounding. "So we're probably going to work in the next couple of years to try and unravel this," Emmert said.

Ice extent for July 2010 was the second lowest in the satellite record for the month. The linear rate of decline of July ice extent over the period 1979 to 2010 is now 6.4% per decade.

Older, thicker ice melting in the southern Beaufort Sea This past winter's negative phase of the Arctic Oscillation transported old ice (four, five, and more years old) from an area north of the Canadian Archipelago. The ice was flushed southwards and westward into the Beaufort and Chukchi seas, as noted in our April post. Ice age data show that back in the 1970s and 1980s, old ice drifting into the Beaufort Sea would generally survive the summer melt season. However, the old, thick ice that moved into this region is now beginning to melt out, which could further deplete the Arctic’s remaining store of old, thick ice. The loss of thick ice has been implicated as a major cause of the very low September sea ice minima observed in recent years.

Ron Kwok of the Jet Propulsion Laboratory (JPL) reports that Nares Strait, the narrow passageway between northwest Greenland and Ellesmere Island is clear of the ice “arch" that usually plugs southward transport of the old, thick ice in the Lincoln Sea. Typically the ice arch forms in winter and breaks up in early July. This year the arch formed around March 15th and lasted only 56 days, breaking up in May. In 2007 the ice arch did not form at all, allowing twice as much export through Nares Strait than the annual mean. Although the export of sea ice out of the Arctic Ocean through Nares Strait is very small in comparison to the export through Fram Strait, the Lincoln Sea contains some of the Arctic’s thickest ice.

Migration is dwindling worldwide, Middleton says, and preserving some of the last large mammal migrations in North America has become a key conservation concern. Satellite images of where the elk roam now suggest what’s gone wrong with their migration, Middleton reported June 14 at the annual meeting of the American Society of Mammalogists. Images show that the period when grasslands are thriving and green with prime nutrition for grazers shrank by 40 percent between 1989 and 2009, he said. This premature grassland brownout fits with weather station data showing that over the past 21 years, the average July temperature in the migrants’ high-elevation summer range has risen more than 4 degrees Celsius, Middleton said. On top of that, nearly a decade of drought worse than the Dust Bowl dry-out has parched the Yellowstone region. In contrast, satellite images show little change in the greening of vegetation at the lower elevation, Middleton said. Elk remaining there not only have a more stable summer food source, but can nip over to some scattered agricultural outfits to take advantage of irrigated vegetation.

Satellite imagery of this remote area at 81 degrees N latitude and 61 degrees W longitude, about 620 miles [1,000 km] south of the North Pole, reveals that Petermann Glacier lost about one-quarter of its 43-mile long [70 km] floating ice-shel

The new ice island has an area of at least 100 square miles and a thickness up to half the height of the Empire State Building. “The freshwater stored in this ice island could keep the Delaware or Hudson rivers flowing for more than two years. It could also keep all U.S. public tap water

The last time such a massive ice island formed was in 1962 when Ward Hunt Ice Shelf calved a 230 square-mile island, smaller pieces of which became lodged between real islands inside Nares Strait. Petermann Glacier spawned smaller ice islands in 2001 (34 square miles) and 2008 (10 square miles). In 2005, the Ayles Ice Shelf disintegrated and became an ice island (34 square miles) about 60 miles to the west of Petermann Fjord.

"Frankly, I was expecting that we'd see large temperature increases later this century with higher greenhouse gas levels and global warming," Stanford climate scientist Noah Diffenbaugh, who headed up the research, said in a prepared statement. "I did not expect to see anything this large within the next three decades."

Phytoplankton are microscopic marine organisms capable of photosynthesis, just like terrestrial plants. They float in the upper layers of the oceans, provide much of the oxygen we breathe and account for about half of the total organic matter on Earth. A 40 per cent decline would represent a massive change to the global biosphere."If this holds up, something really serious is underway and has been underway for decades. I've been trying to think of a biological change that's bigger than this and I can't think of one," said marine biologist Boris Worm of Canada's Dalhousie University in Halifax, Nova Scotia. He said: "If real, it means that the marine ecosystem today looks very different to what it was a few decades ago and a lot of this change is happening way out in the open, blue ocean where we cannot see it. I'm concerned about this finding."The researchers studied phytoplankton records going back to 1899 when the measure of how much of the green chlorophyll pigment of phytoplankton was present in the upper ocean was monitored regularly. The scientists analysed about half a million measurements taken over the past century in 10 ocean regions, as well as measurements recorded by satellite.They found that phytoplankton had declined significantly in all but two of the ocean regions at an average global rate of about 1 per cent per year, most of which since the mid 20th Century. They found that this decline correlated with a corresponding rise in sea-surface temperatures – although they cannot prove that warmer oceans caused the decline.The study, published in the journal Nature, is the first analysis of its kind and deliberately used data gathered over such a long period of time to eliminate the sort of natural fluctuations in phytoplankton that are known to occur from one decade to the next due to normal oscillations in ocean temperatures, Dr Worm said. "Phytoplankton are a critical part of our planetary life support system. They produce half of the oxygen we breathe, draw down surface CO2 and ultimately support all of our fishes." he said.But some scientists have warned that the Dalhousie University study may not present a realistic picture of the true state of marine plantlife given that phytoplankton is subject to wide, natural fluctuations."Its an important observation and it's consistent with other observations, but the overall trend can be overinterpreted because of the masking effect of natural variations," said Manuel Barange of the Plymouth Marine Laboratory and a phytoplankton expert.

However, the Dalhousie scientists behind the three-year study said they have taken the natural oscillations of ocean temperatures into account and the overall conclusion of a 40 per cent decline in phytoplankton over the past century still holds true. "Phytoplankton are the basis of life in the oceans and are essential in maintaining the health of the oceans so we should be concerned about its decline."It's a very robust finding and we're very confident of it," said Daniel Boyce, the lead author of the study."Phytoplankton is the fuel on which marine ecosystems run. A decline of phytoplankton affects everything up the food chain, including humans," Dr Boyce said.

Phytoplankton is affected by the amount of nutrients the well up from the bottom of the oceans. In the North Atlantic phytoplankton "blooms" naturally in spring and autumn when ocean storms bring nutrients to the surface. One effect of rising sea temperatures has been to make the water column of some regions nearer the equator more stratified, with warmer water sitting on colder layers of water, making it more difficult for nutrients to reach the phytoplankton at the sea surface.Warmer seas in tropical regions are also known to have a direct effect on limiting the growth of phytoplankton.