Monday, September 17, 2012

Melting the Arctic ice

While it is fun to slap around the climate change denialists, this friends is getting scary.  Nothing good ever happens when the jet stream gets a kink in it.  Two winters ago, a kink brought us mega piles of snow.  Last winter, we hardly had a winter at all—70°F in freaking March.  One thing we have learned about climate change—weather patterns are hard to predict but we can always predict something will be very extreme.

Arctic sea ice melt 'may bring harsh winter to Europe'

The unprecedented loss of polar sea ice may lead to 'wild extremes' in the UK and northern Europe, say researchers

Stephen Leahy in Uxbridge, Canada, Friday 14 September 2012

The record loss of Arctic sea ice this summer may mean a cold winter for the UK and northern Europe. The region has been prone to bad winters after summers with very low sea ice, such as 2011 and 2007, said Jennifer Francis, a researcher at Rutgers University.

"We can't make predictions yet … [but] I wouldn't be surprised to see wild extremes this winter," Francis told the Guardian.

This year's ice melt has broken the 2007 record by an an area larger than the state of Texas.

Polar ice experts "thought that it would be many years until we again saw anything like we saw in 2007", said Mark Serreze, director of the National Snow and Ice Data Centre in Colorado.

The unprecedented expanse of ice-free Arctic Ocean has been absorbing the 24-hour sun over the short polar summer. The heat in the water must be released into the atmosphere if the ice is to re-form this autumn. "This is like a new energy source for the atmosphere," said Francis.

This heat and water vapour will affect the all-important jet stream – the west-to-east winds that are the boundary between cold Arctic and the warm mid-latitudes. Others researchers have already shown that the jet stream has been shifting northwards in recent years. Francis and colleagues have recently documented that the jet stream is also slowing down.

"The jet stream is clearly weaker," said Francis. That means weather systems, be it rain or dry conditions, are slow to move on and last longer. Ultimately this can result in "blocking" events, such as the conditions that produced the terrible heatwave in western Russia during the summer of 2010, she said.

This summer, Greenland experienced a similar blocking anti-cyclone, resulting in a record surface melting of its ice sheet. It is not possible to directly connect that block to the prolonged US heatwave and drought this summer, Francis said. However "blocks act like a traffic jam, slowing down weather patterns elsewhere".

These changes are happening much earlier than scientists thought, said James Overland, an oceanographer and researcher at the University of Washington.

"We've only had a little bit of global warming so far," Overland said. more
I have been saying for at least five years—the further you get from the equator, the oceans, or sea level, the more apparent climate change is.  Hard to miss a melting polar ice cap.

Vanishing Arctic ice is the planet's white flag of surrender

The planet's last great global ice melt left a benign and balmy climate in which civilisation was cradled: the new great melting heralds a grave threat to civilisation

Our planet is waving the white flag of surrender. But as the polar flag becomes ever more tattered, with holes scorched by hotter ocean waters, humanity pumps ever more globe-warming gases into the air.

The story of the Arctic ice cap is the story of modern environmentalism. In 1968, as satellites began to document the vast ice field blanketing the north pole, the iconic Earthrise image was beamed back to the ground. It revealed a planet of awesome beauty, deep blue oceans, verdant continents and crowned with at least 8m square kilometres of gleaming ice. The image kickstarted the global green movement.

In 2007, a new record was set for the minimum summer sea ice cover in the Arctic had halved. This furious flag waving attracted attention. That year, the world's scientists declared the end of any doubt that our addiction to burning fossil fuels was changing the face of the planet. Al Gore expounded his inconvenient truth and the world seemed set to act.

Today, that 2007 record is smashed and the shredded white flag is now flickering rathering than flashing. But the danger is greater than even, even if the alarm signal is frayed.

The last great global ice melt the planet witnessed came 10,000 years ago at the end of a deep ice age. As glaciers retreated, a benign and balmy climate emerged in which the human race has flourished. Our entire civilisation is built on the warm soils left as the ice sheets melted.

This new great melting heralds the polar opposite: the gravest of threats to civilisation. Removing the lid from the pole will release heat equivalent to fast-forwarding human-caused climate change by two decades, say scientists.

Will this be the first great tipping point to tumble the world into a new and hostile climate regime, as the cooling, reflective ice vanishes? Will the new, warm Arctic radically alter the temperate weather enjoyed by Europeans, for whom global warming has seemed a distant concern?

We seem to be prepared to take that chance. The shrinking ice has not opened new leads for decisive global action to tackle climate change. Instead, in a vicious irony, the new channels are being exploited for oil and gas exploration, unearthing more of the very fuels driving the warming.

Decades from now, will today's record sea ice low be seen as the moment when our Earthly paradise gave up the ghost and entered a hellish new era? I sincerely hope not, but with this global distress signal failing to attract attention, I fear the worst. more
Screw around with the sea levels and coastal habitats wil start dumping billions of tons of carbon dioxide into the atmosphere.  This is a classic example of a positive feedback loop.
SEP 06, 2012

Destroyed coastal habitats produce significant greenhouse gas

Destruction of coastal habitats may release as much as 1 billion tons of carbon into the atmosphere each year, 10 times higher than previously reported, according to a new Duke led study.

Published online this week in PLOS ONE, the analysis provides the most comprehensive estimate of global carbon emissions from the loss of these coastal habitats to date: 0.15 to 1.2 billion tons. It suggests there is a high value associated with keeping these coastal-marine ecosystems intact as the release of their stored carbon costs roughly $6-$42 billion annually.

“On the high end of our estimates, emissions are almost as much as the carbon dioxide emissions produced by the world’s fifth-largest emitter, Japan,” said Brian Murray, director for economic analysis at Duke’s Nicholas Institute for Environmental Policy Solutions. “This means we have previously ignored a source of greenhouse gas emissions that could rival the emissions of many developed nations.”

This carbon, captured through biological processes and stored in the sediment below mangroves, sea grasses and salt marshes, is called “blue carbon.” When these wetlands are drained and destroyed, the sediment layers below begin to oxidize. Once this soil, which can be many feet deep, is exposed to air or ocean water it releases carbon dioxide over days or years.

“There’s so little data out there on how much carbon might be released when these ecosystems are disturbed,” said Oregon State University’s Daniel Donato, co-lead author of the paper. “With this analysis we tried to reduce some of that uncertainty by identifying some ‘bookends’ that represent the lowest and highest probable emissions, given the information available.” more

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