Between May 2000 and August 2006, Brazil
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by Robert Goodland and Jeff Anhang
Livestock and Climate Change: What if the key actors in climate change are…cows, pigs, and chickens?
The environmental impact of the lifecycle and supply chain of animals raised for food has been vastly underestimated, and in fact accounts for at least half of all human-caused greenhouse gases (GHGs), according to Robert Goodland and Jeff Anhang, co-authors of “Livestock and Climate Change”.
A widely cited 2006 report by the United Nations Food and Agriculture Organization, Livestock’s Long Shadow, estimates that 18 percent of annual worldwide GHG emissions are attributable to cattle, buffalo, sheep, goats, camels, pigs, and poultry. But recent analysis by Goodland and Anhang finds that livestock and their byproducts actually account for at least 32.6 billion tons of carbon dioxide per year, or 51 percent of annual worldwide GHG emissions.
Between May 2000 and August 2006, Brazil
By Steve Connor, Science Editor
Tuesday, 16 December 2008
Scientists have found the first unequivocal evidence that the Arctic region is warming at a faster rate than the rest of the world at least a decade before it was predicted to happen.
Climate-change researchers have found that air temperatures in the region are higher than would be normally expected during the autumn because the increased melting of the summer Arctic sea ice is accumulating heat in the ocean. The phenomenon, known as Arctic amplification, was not expected to be seen for at least another 10 or 15 years and the findings will further raise concerns that the Arctic has already passed the climatic tipping-point towards ice-free summers, beyond which it may not recover.
The Arctic is considered one of the most sensitive regions in terms of climate change and its transition to another climatic state will have a direct impact on other parts of the northern hemisphere, as well more indirect effects around the world.
Although researchers have documented a catastrophic loss of sea ice during the summer months over the past 20 years, they have not until now detected the definitive temperature signal that they could link with greenhouse-gas emissions.
However, in a study to be presented later today to the annual meeting of the American Geophysical Union in San Francisco, scientists will show that Arctic amplification has been under way for the past five years, and it will continue to intensify Arctic warming for the foreseeable future.
Computer models of the global climate have for years suggested the Arctic will warm at a faster rate than the rest of the world due to Arctic amplification but many scientists believed this effect would only become measurable in the coming decades.
However, a study by scientists from the US National Snow and Ice Data Centre (NSIDC) in Colorado has found that amplification is already showing up as a marked increase in surface air temperatures within the Arctic region during the autumn period, when the sea ice begins to reform after the summer melting period.
Julienne Stroeve, of the NSIDC, who led the study with her colleague Mark Serreze, said that autumn air temperatures this year and in recent years have been anomalously high. The Arctic Ocean warmed more than usual because heat from the sun was absorbed more easily by the dark areas of open water compared to the highly reflective surface of a frozen sea. “Autumn 2008 saw very strong surface temperature anomalies over the areas where the sea ice was lost,” Dr Stroeve told The Independent ahead of her presentation today.
“The observed autumn warming that we’ve seen over the Arctic Ocean, not just this year but over the past five years or so, represents Arctic amplification, the notion that rises in surface air temperatures in response to increased atmospheric greenhouse gas concentrations will be larger in the Arctic than elsewhere over the globe,” she said. “The warming climate is leading to more open water in the Arctic Ocean. As these open water areas develop through spring and summer, they absorb most of the sun’s energy, leading to ocean warming.
“In autumn, as the sun sets in the Arctic, most of the heat that was gained in the ocean during summer is released back to the atmosphere, acting to warm the atmosphere. It is this heat-release back to the atmosphere that gives us Arctic amplification.”
Temperature readings for this October were significantly higher than normal across the entire Arctic region – between 3C and 5C above average – but some areas were dramatically higher. In the Beaufort Sea, north of Alaska, for instance, near-surface air temperatures were more than 7C higher than normal for this time of year. The scientists believe the only reasonable explanation for such high autumn readings is that the ocean heat accumulated during the summer because of the loss of sea ice is being released back into the atmosphere from the sea before winter sea ice has chance to reform.
“One of the reasons we focus on Arctic amplification is that it is a good test of greenhouse warming theory. Even our earliest climate models were telling us that we should see this Arctic amplification emerge as we lose the summer ice cover,” Dr Stroeve said. “This is exactly what we are not starting to see in the observations. Simply put, it’s a case of we hate to say we told you so, but we did,” she added.
Computer models have also predicted totally ice-free summers in the Arctic by 2070, but many scientists now believe that the first ice-free summer could occur far earlier than this, perhaps within the next 20 years.
Ian Sample, science correspondent
guardian.co.uk, Monday 15 December 2008 17.30 GMT
European fisheries are at risk of widespread collapse if responsibility for setting catch sizes is not given over to an independent body, a leading marine scientist said today.
The warning follows research that reveals EU ministers have consistently ignored scientific advice on catch limits, and agreed quotas up to 140% higher than sustainable levels.
The systematic mismanagement of fisheries was akin to a “doctor assisting the suicide of a patient”, that ultimately “condemns the fishing industry to extinction,” said Callum Roberts, professor of marine conservation at the University of York.
The bleak assessment of the health of Europe’s fisheries comes as EU ministers prepare to agree new quotas later this week.
In the 1970s, three quarters of Europe’s fisheries were in a healthy or slightly at risk state, but today more than half are in danger. Despite scientific advice, which in some cases, such as cod, has called for complete regional bans on fishing, ministers continue to argue for quotas above sustainable levels.
Fish stocks and sustainable catch limits are determined each year by scientists at the International Council for the Exploration of the Sea (ICES), but ministers use this only as a starting point when they meet to decide annual fishing quotas.
Roberts argues that instead of deciding quotas, ministers should only be involved in working how the scientifically-agreed catch limits are divided among member states.
“It’s better to have the decision making independent of politics and independent of industry. If we don’t change our ways we’ll have less and less to catch and we’ll end up eating plankton,” he said.
Research by Roberts’s team at York shows that quotas set by EU ministers over the past 10 years have exceeded limits proposed by scientists by 45% for cod, 140% for hake, 93.6% for prawns and 14% for plaice.
“It’s a waste of taxpayer’s money to do all this research on fish stocks and then ignore it,” Roberts said.
Mike Kaiser, a marine conservationist at the University of Bangor said that some fisheries were beginning to understand the importance of managing fish stocks sustainably, but said the European Commission must take the lead on tackling the issue of dwindling stocks.
“We’ve got to the point now in the UK where we realise that things have got to change. The problem is that’s only one nation. If we are rowing against the tide as a nation it’ll have very little impact,” he said.
Arctic scientists discover new global warming threat as melting permafrost releases millions of tons of a gas 20 times more damaging than carbon dioxide
By Steve Connor, Science Editor
Tuesday, 23 September 2008
The first evidence that millions of tons of a greenhouse gas 20 times more potent than carbon dioxide is being released into the atmosphere from beneath the Arctic seabed has been discovered by scientists.
The Independent has been passed details of preliminary findings suggesting that massive deposits of sub-sea methane are bubbling to the surface as the Arctic region becomes warmer and its ice retreats.
Underground stores of methane are important because scientists believe their sudden release has in the past been responsible for rapid increases in global temperatures, dramatic changes to the climate, and even the mass extinction of species. Scientists aboard a research ship that has sailed the entire length of Russia’s northern coast have discovered intense concentrations of methane – sometimes at up to 100 times background levels – over several areas covering thousands of square miles of the Siberian continental shelf.
In the past few days, the researchers have seen areas of sea foaming with gas bubbling up through “methane chimneys” rising from the sea floor. They believe that the sub-sea layer of permafrost, which has acted like a “lid” to prevent the gas from escaping, has melted away to allow methane to rise from underground deposits formed before the last ice age.
They have warned that this is likely to be linked with the rapid warming that the region has experienced in recent years.
Methane is about 20 times more powerful as a greenhouse gas than carbon dioxide and many scientists fear that its release could accelerate global warming in a giant positive feedback where more atmospheric methane causes higher temperatures, leading to further permafrost melting and the release of yet more methane.
The amount of methane stored beneath the Arctic is calculated to be greater than the total amount of carbon locked up in global coal reserves so there is intense interest in the stability of these deposits as the region warms at a faster rate than other places on earth.
Orjan Gustafsson of Stockholm University in Sweden, one of the leaders of the expedition, described the scale of the methane emissions in an email exchange sent from the Russian research ship Jacob Smirnitskyi.
“We had a hectic finishing of the sampling programme yesterday and this past night,” said Dr Gustafsson. “An extensive area of intense methane release was found. At earlier sites we had found elevated levels of dissolved methane. Yesterday, for the first time, we documented a field where the release was so intense that the methane did not have time to dissolve into the seawater but was rising as methane bubbles to the sea surface. These ‘methane chimneys’ were documented on echo sounder and with seismic [instruments].”
At some locations, methane concentrations reached 100 times background levels. These anomalies have been seen in the East Siberian Sea and the Laptev Sea, covering several tens of thousands of square kilometres, amounting to millions of tons of methane, said Dr Gustafsson. “This may be of the same magnitude as presently estimated from the global ocean,” he said. “Nobody knows how many more such areas exist on the extensive East Siberian continental shelves.”
“The conventional thought has been that the permafrost ‘lid’ on the sub-sea sediments on the Siberian shelf should cap and hold the massive reservoirs of shallow methane deposits in place. The growing evidence for release of methane in this inaccessible region may suggest that the permafrost lid is starting to get perforated and thus leak methane… The permafrost now has small holes. We have found elevated levels of methane above the water surface and even more in the water just below. It is obvious that the source is the seabed.”
The preliminary findings of the International Siberian Shelf Study 2008, being prepared for publication by the American Geophysical Union, are being overseen by Igor Semiletov of the Far-Eastern branch of the Russian Academy of Sciences. Since 1994, he has led about 10 expeditions in the Laptev Sea but during the 1990s he did not detect any elevated levels of methane. However, since 2003 he reported a rising number of methane “hotspots”, which have now been confirmed using more sensitive instruments on board the Jacob Smirnitskyi.
Dr Semiletov has suggested several possible reasons why methane is now being released from the Arctic, including the rising volume of relatively warmer water being discharged from Siberia’s rivers due to the melting of the permafrost on the land.
The Arctic region as a whole has seen a 4C rise in average temperatures over recent decades and a dramatic decline in the area of the Arctic Ocean covered by summer sea ice. Many scientists fear that the loss of sea ice could accelerate the warming trend because open ocean soaks up more heat from the sun than the reflective surface of an ice-covered sea.
RESOURCES: NASA Scientist: Fix Climate or 'We're Toast' (Live Science) Prince Charles: Eighteen months to stop climate change disaster (Telegraph) The world may have nothing left to save tomorrow: Maneka Gandhi (India eNews) Al Gore: "Planetary Emergency!" (Fog City Journal)
According to the UN IPCC report “Livestock’s Long Shadow,”
livestock production is the greatest contributor to global warming.
(including aviation accounts for 3.5%)
RESOURCES: Livestock’s Long Shadow(table 3.12 p 113) (UN FAO, 2007) US. GHG Emissions Flowchart (World Resources Institute)
Tropical forests hold half of the world’s species which are becoming extinct an alarming rate due to deforestation for meat production.
Oceans empty of fish and ecosystems are destroyed due to industrial fishing, animal wastes, and agricultural pollutants.
RESOURCES: Livestock’s Long Shadow (p32, p185-p188) (UN Food and Agriculture Organization, 2007) Why are rainforests so important? (Cool Earth) Salt-Water Fish Extinction Seen By 2048 (CBS News)
Pollution strength up to 160 times greater than raw municipal waste.
Animal wastes contribute to large oceanic “dead zones,” which extended to nearly 7,903 sq. miles in the Gulf of Mexico during Summer of 2007.
In the U.S. alone, livestock is responsible for:
RESOURCES: America's Animal Factories How States Fail to Prevent Pollution from Livestock Wast (Natural Resources Defense Council) NOAA and Louisiana Scientists Predict Largest Gulf of Mexico “Dead Zone” on Record This Summer (National Oceanic and Atmospheric Administration) Livestock’s Long Shadow(executive summary, p.xxii) (UN Food and Agriculture Organization, 2007)