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Global warming deniers are on thin ice
Sea ice in the Arctic thinned dramatically between the 2004 and 2008 winters, with thin seasonal ice supplanting thick older ice as the dominant type for the first time on record, reported scientists from NASA and the University of Washington.
The scientists used measurements from NASA's ICESat satellite to make the first basin-wide estimate of the Arctic Ocean's ice cover.
They found overall Arctic sea ice has thinned by about 17 centimetres a year, for a 0.67 metre total over four years.

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Global warming is 'irreversible'
A team of environmental researchers in the US has warned many effects of climate change are irreversible.
The scientists concluded global temperatures could remain high for 1,000 years, even if carbon emissions can somehow be halted.
Their report was sponsored by the US Department of Energy and comes as President Obama announces a review of vehicle emission standards.

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Researchers of the INSU-CNRS, in collaboration with chemists at a CNRS research unit, have explained  the strong conductivity of the Earth's upper mantle is due to the presence of molten carbonates. Thanks to a ultra-powerful device, they highlighted the extremely high conductivity of this carbon form. Published in the 28 November issue of Science, their work revealed the percentage of carbon inside the upper mantle. This composition can itself be directly related to the quantity of carbon dioxide emitted by 80% of the volcanos. The  result is important to quantify the carbon cycle, which plays a major role in the greenhouse effect.

Geologists have long claimed that significant amounts of carbon have been present in the Earth's mantle for thousands of years. Until now, there was very little direct proof of this hypothesis, and samples from the surface of the mantle contained only very small quantities of carbon. Also, for the last thirty years, scientists have been unable to explain the conductivity of the mantle, which is crossed by natural electrical currents at depths of 70 to 350 kms, even though olivine, one of the main mineral components of the upper mantle, is completely isolating.
To explain these phenomena, researchers from the Institut des Sciences de la Terre d'Orléans  looked into liquid carbonates, one of the most stable forms of carbon within the mantle, along with graphite and diamond. The Masai volcano is Tanzania is the only place in the world where these carbonates can be observed. Elsewhere, the carbonates are dissolved in basalts and emitted into the atmosphere in gaseous form, as CO2.
Based on lab measurements at CNRS's CEMHTI, the researchers established the high conductivity of molten carbonates. Their conductivity is 1000 times higher than that of basalt, which was previously thought to be the only potential conductor in the mantle. Fabrice Gaillard and his team have shown that the conductivity of the Earth's mantle is a result of the presence of small amounts of molten carbonates between chunks of solid rock.
This work shows that the electrical characteristics of the asthenosphere, the conductive part of the upper mantle, are directly connected to the amount of carbonate in the layer. The work also points to varying carbon distribution according to the regions and depth of the mantle. The researchers calculated that the amount of carbon present as liquid carbonate directly within the asthenosphere is between 0.003 and 0.025%, which seems low but makes it possible to explain the amounts of CO2 emitted into the atmosphere by 80% of volcanoes .

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Frozen arctic soil contains nearly twice the greenhouse-gas-producing organic material as was previously estimated, according to recently published research by University of Alaska Fairbanks scientists.

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Virgin Galactic is to look at carrying scientific instruments on board one of its space tourism vehicles to gather data on climate change.
The company will join up with the US National Oceanic and Atmospheric Administration (Noaa) for the venture.
The first instrument would provide data on atmospheric composition - particularly greenhouse gases.

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Scientists will this week (Friday 26 Sept) announce the annual update on the global carbon figures. They report that CO2 emissions from burning fossil fuels and cement manufacturing continue to increase rapidly despite international agreements to limit emissions of greenhouse gases.
The latest estimates of annual CO2 emissions indicate also that the pattern of emissions has changed markedly since the drafting of the United Nations Framework Convention on Climate Change in 1992, and that more than half of global emissions are now from the so-called developing countries. Forests and oceans - the Earths natural sinks - absorbed 54% of the CO2 emissions since 2000, down by 3% compared to 1959-2000.

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Ice Age lesson predicts a faster rise in sea level
If the lessons being learned by scientists about the demise of the last great North American ice sheet are correct, estimates of global sea level rise from a melting Greenland ice sheet may be seriously underestimated.
Writing this week (Aug. 31) in the journal Nature Geoscience, a team of researchers led by University of Wisconsin-Madison geologist Anders Carlson reports that sea level rise from greenhouse-induced warming of the Greenland ice sheet could be double or triple current estimates over the next century.

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Typhoons bury Carbon
A single typhoon in Taiwan buries as much carbon in the ocean -- in the form of sediment -- as all the other rains in that country all year long combined.
That's the finding of an Ohio State University study published in a recent issue of the journal Geology.

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Large amounts of ozone around 50% more than predicted by the worlds state-of-the-art climate models are being destroyed in the lower atmosphere over the tropical Atlantic Ocean.
A team of scientists from the National Centre for Atmospheric Science and the Universities of York and Leeds made the discovery, which is significant because ozone in the lower atmosphere acts as a greenhouse gas and its destruction also leads to the removal of the third most abundant greenhouse gas; methane.

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Delegates at the UN summit in Bali have agreed a deal on curbing climate change after days of bitter wrangling.
Agreement was reached after a U-turn from the US, which had wanted firmer commitments from developing countries.

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