Research scientists from the University of Exeter in the UK have provided the first evidence that that reducing levels of fishing is a viable way of protecting coral reefs from some of the damage caused by climate change.

Increases in ocean surface water temperatures subject coral reefs to stresses that lead quickly to mass bleaching. The problem is intensified by ocean acidification, which is also caused by increased carbon dioxide. This decreases the ability of corals to produce calcium carbonate, which is the material that reefs are made of.

Coral bleaching in the Maldives

Approximately 2% of the world’s coral reefs are located within marine reserves, where human activity, like dredging and fishing. is prohibited.

The researchers conducted surveys of ten sites inside and outside marine reserves in the Bahamas which had been severely damaged by bleaching and then by hurricane Frances in the summer of 2004.

After two and a half years, coral cover in protected areas had increased by an average of 19%, while reefs in non-reserve sites showed no recovery.

According to Professor Peter Mumby of the University of Exeter, "In order to protect reefs in the long-term, we need radical action to reduce CO2 emissions. However, our research shows that local action to reduce the effects of fishing can contribute meaningfully to the fate of reefs. This sort of evidence may help persuade governments to reduce the fishing of key herbivores like parrotfishes and help reefs cope with the inevitable threats posed by climate change."

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A new type of natural-gas electric power plant, which has been proposed by MIT researchers, could provide electricity with zero carbon dioxide emissions to the atmosphere, at costs comparable to or less than conventional natural-gas plants, and even to coal-burning plants.

Postdoctoral Associate Thomas Adams and Paul I. Barton, the Lammot du Pont Professor of Chemical Engineering, have proposed a system that uses solid-oxide fuel cells, which produce power from fuel without burning it. The system does not require any new technology but combines existing components or ones that are already well under development, in a novel configuration.

According to Thomas Adams, unless a price is placed on carbon emissions, "the cheapest fuel (for  generating electricity) will always be pulverized coal." But as soon as there is some form of carbon pricing at more than about $15 per tonne of emitted carbon dioxide "ours is the lowest price option."

Although no full-scale plants using this system have yet been built, the basic principles have been demonstrated in a number of smaller units including a 250-kilowatt plant. Prototype megawatt-scale plants are planned for completion around 2012.

Utility-scale power plants would be on the order of 500 megawatts but because fuel cells, unlike conventional turbine-based generators, are inherently modular, once the system has been proved at small size it can easily be scaled up. "You don’t need one large unit," Adams explains. "You can do hundreds or thousands of small ones, run in parallel."

He says that practical application of such systems is "not very far away at all" and could be ready for commercialization within a few years.

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Closing the hole in the ozone is seen as the world’s greatest environmantal restoration achievement but there’s a hitch …

Under the Montreal Protocol, chloroflurocarbons (CFCs) were phased out and replaced with the less damaging hydrochlorofluorocarbons (HCFCs) as an interim measure. HCFCs have now become the standard working coolant in refrigerators, air conditioners and aerosol cans.

But HCFCs are still damaging to the ozone layers and, in the longer term, hydrofluorocarbons (HFCs) were promoted as the best alternative. From January 1, 2010, the world’s developed nations must cut HCFC consumption and production by 75 percent. It will then become illegal to import, produce or sell HCFC-22 (Freon) and HCFC-142b, the ubiquitous refrigerants, for use in new equipment.

The problem is that, whereas HFCs do not destroy the ozone layer, they can be thousands of times more harmful to Earth’s climate than carbon dioxide.

The underlying problem is that the characteristics which make a good refrigerant are the ability to trap heat and durability - exactly the same characteristics that make a powerful greenhouse gas.

Ironically, the best solution may well be to use CO2 as a refrigerant. CO2 can remove heat from the air. The process starts when a refrigerator’s compressor condenses CO2 into a liquid, raising its pressure and temperature. The CO2 is then transferred to a  a radiator on the back or bottom of the fridge where the heat is released. The CO2 then travels through an expansion valve, reducing the pressure and causing it to rapidly expand into vapor. As the CO2 evaporates it absorbs heat, cooling the air inside the refrigerator compartment.

The difficulty with CO2 is that it must be used at a much higher pressure than HFC refrigerants, and therefore requires stronger piping.

Coca-Cola began testing the use of CO2 as a refrigerant in vending machines and other retail refrigerators in China during the Olympics and PepsiCo is now testing these vending machines in Washington, D.C.

(Based on sources including Scientific American)

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It is generally argued that livestock are the cause of about 18% of worldwide greenhouse gas emissions. The figure comes from a 2006 United Nations Food and Agriculture Organisation report titled "Livestock’s Long Shadow". A new study by Robert Goodland and Jeff Anhang, published in Worldwatch magazine, argues that this greatly understimates the impact of livestock and that the real figure should be about 50%.

Robert Goodland and Jeff Anhang argue that the FAO underestimated the impact of livestock in serveral ways:
Click here to read the rest of this entry.

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A technical workshop of leading world marine and climate change scientists has released a statement saying that, not only are targets such as 450 ppm of carbon dioxide inadequate to save the world’s coral reefs,  but even current levels of carbon dioxide are too high for the long-term viability of the reefs.

The workshop, hosted by the Zoological Society of London (ZSL), the International Programme on the State of the Ocean (IPSO), and the Royal Society, stated that:

"Temperature-induced mass coral bleaching causing widespread mortality on the Great Barrier Reef and many other reefs of the world started when atmospheric CO2 exceeded 320ppm.

"At today’s level of 387ppm CO2, reefs are seriously declining and time-lagged effects will result in their continued demise with parallel impacts on other marine and coastal ecosystems

"Proposals to limit CO2 levels to 450ppm will not prevent the catastrophic loss of coral reefs from the combined effects of climate change and ocean acidification.

"To ensure the long-term viability of coral reefs atmospheric carbon dioxide level must be reduced significantly below 350ppm.

"In addition to major reductions in CO2 emissions, achieving this safe level will require the active removal of CO2 from the atmosphere."

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Researchers from the University of Tasmania are developing a chemistry process which could help tackle climate change by converting the polluting chemicals into environmentally friendly ones.

The head of the University’s School of Chemistry, Brian Yates, said that the experiments attempt to break the strong molecular bonds of pollutants such as carbon dioxide to produce less toxic compounds.

"It’s not looking at limiting the carbon emissions, which of course we’re very aware of, but taking what’s there in the atmosphere already," he said. "At the moment it’s turning it into an ester.  Esters are natural compounds that occur as flavourings and fragrances."

The research team is collaborating with chemists from California who will test the process.

Professor Yates says any practical application is still at least five years away.

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Physicists at Columbia University in New York say that they have made a breakthrough in developing a device which can “suck” carbon dioxide out the air.

Scientists have been sceptical about the possibility of using “scrubbers” to extract carbon dioxide from the air because, although it is easy to get chemicals to absorb carbon dioxide, it takes a large amount of energy to release the carbon dioxide for use or storage. The Columbia University team, led by Klaus Lackner, says that it can capture the carbon dioxide using ion exchange membranes (commonly used in purifying water) and then make the membranes “exhale” the carbon dioxide using just humid air.

The team plans to demonstrate a prototype, capable of extracting a tonne of carbon dioxide a day from the air, within two years. The prototype would fit in a shipping container and cost about $200,000. It could be connected to a greenhouse so that the captured carbon dioxide could be used to stimulate plant or algae growth for food, fuel or fertilizer.

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Bridgestone Europe has conducted a survey of over 20,000 passenger cars which found that 93.5% of them have under-inflated tyres. Under-inflated tyres increase rolling resistance, reduce safety and increase fuel consumption. Bridgestone’s engineers calculated that, if this figure apples to all of the cars in Europe, then they are wasting over 8 billion litres of fuel per year and generating almost 8 million extra tonnes of carbon dioxide.

If the same figures apply to cars worldwide, then we are wasting almost 40 billion litres of fuel and unnecessarily generating about 40 million tonnes of carbon dioxide.

Having underinflated tyres is often caused by incorrectly adjusting pressure when the tyre is hot. If you’re unsure about the right way to check you tyre pressure and adjust for heat, take a minute to have a look at this video from Michelin.

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