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Gas-friendly cows an emission possible to cut global warming
Richard Macey; June 22, 2006; Sydney Morning Herald
SUCCESS in the search for a bull that eats and burps less is tipped to curb (Australia's) greenhouse emissions by more than half a million tonnes over the next 25 years.
Scientists from NSW's Department of Primary Industries have been working for the past 15 years to find a way to breed more efficient beef cattle.
When cattle munch a meal, explained one researcher, Robert Herd, much of the food is converted by fermentation into methane gas. "Ten per cent of the energy eaten is just burped off," he said, adding that feed was the biggest cost in raising beef cattle.
His team found that certain cattle can eat significantly less food, and thus belch less gas, but somehow grow as much steak as regular animals.
They also discovered the cattle carry a protein that could be used as a genetic flag to signal the special talent.
After a decade of research, the scientists came up with a blood analysis that has been developed into a commercial test for selecting bulls able to breed the most food-efficient cows and steers.
Although it has been developed to cut farming costs, the scientists now believe the burp-reduced cattle will also help fight global warming, because methane is also a greenhouse gas, many times more powerful than carbon dioxide.
Another member of the research team, Andrew Alford, has calculated that even by the most conservative estimates, the cattle should reduce Australia's methane emissions by 568,100 tonnes over 25 years - a 3 per cent reduction in the gas belched by beef herds.
If methane-efficient cattle were used by all farmers, the reduction could be up to 16 per cent. Mr Alford said that if a carbon trading program was introduced, the reduced belching could even be worth money to farmers - about $2.16 per cow each year.
"The estimated 568,100 tonnes of methane abated over the 25 years could, on current values for carbon trading, imply an annual return of $5 million across the national beef industry."
Australia's livestock is blamed for about 12.3 per cent of national greenhouse emissions. Stopping 568,100 tonnes of methane from entering the atmosphere, the scientists said, is equal to blocking 11.9 million tonnes of carbon dioxide.
The leader of the department's methane research effort, Roger Hegarty, said it may be possible to develop other methane-efficient animals, including sheep.
He said that if a tax was ever levied on greenhouse emissions, curbing livestock belching would be crucial for farmers.
Dr Hegarty estimated 95 per cent of methane from beef cattle was belched. The rest, he said, was "flatulence".
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Global Warming Threat Is Seen in Siberian Thaw
By Janet Wilson Times Staff Writer June 16, 2006
Ancient woolly mammoth bones and grasslands locked in the Siberian permafrost are starting to thaw and could potentially unleash billions of tons of carbon dioxide into the atmosphere, accelerating global warming, a team of Russian and American scientists has concluded.
The area involved is vast — 400,000 square miles. If the permafrost continues to thaw and releases heat-trapping carbon dioxide, it could dramatically increase the 730 billion metric tons already in the atmosphere, the scientists said in a study published in today's issue of the journal Science.
"It's like taking food out of your freezer … leave it on your counter for a few days, and it rots," University of Florida botany professor Ted Schuur said in a phone interview from Alaska, describing the process by which decaying animal and plant matter in the soil is converted by bacteria into carbon dioxide, methane and other greenhouse gases.
The research team concluded that previous studies on global warming had not taken into account the deep carbon reserve trapped in permafrost in the northern plains of Siberia and central Alaska.
The scientists said what was most surprising was the size and depth of the terrain that could be affected — a piece two-thirds the size of Alaska and an average of 80 feet deep containing about 500 billion metric tons of carbon.
"It's like finding a new continent under the Earth," lead author Sergey Zimov said in a telephone interview from northern Siberia. He said the vast, carbon-rich area had been buried over many millennia by a unique layer of wind-borne loess dust that covered bones of mammoth, bison, saber-toothed tigers and the abundant grasses they fed on, then froze about 10,000 years ago into permafrost.
Contrary to earlier assumptions that permafrost was as barren as the polar desert, samples taken by the research team found 10 to 30 times as much carbon as in deep soils elsewhere. Schuur said most previous studies looked at samples about 3 feet deep.
Scientists, including this team, are working to document how fast the permafrost is melting. A 2005 study by the U.S. Center for Atmospheric Research estimated that about 10 feet of permafrost would melt in the 21st century, meaning billions of tons of gases could be released if global warming was not slowed or halted.
The Russian-American research team, funded by the National Science Foundation in the U.S., found that carbon stored over tens of thousands of years could bubble up from thawed soil in as little as 100 years.
"Because this is a very sensitive sort of climate, if the permafrost begins to melt, billions of gallons of greenhouse gases will be released from these ancient soils," Zimov said.
The authors said they hoped the findings would spur quicker reductions of greenhouse gas emissions from cars and other sources.
"It's not hopeless," Schuur said. "We're just at the beginning of this cycle, so we can, through the controlling of emissions, have a hope of slowing down this rate of global warming that would slow the melt of the permafrost."
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New research from UC Berkeley and Lawrence Berkeley Laboratory suggests that as carbon dioxide emissions heat the globe, hotter oceans and soils will release stored carbon dioxide, which will in turn kick up the thermostat an extra notch. more
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It was warm at the North Pole 55 million years ago. Cores drilled from the ocean bottom 150 miles from the North Pole show evidence of an Arctic climate that once resembled Florida. Warm water critters and plants reveal temperatures higher than previously believed and higher CO2 levels.
Cores from newly exposed Arctic Ocean bottom add new detail to current climate research; one scientist said, "It's like working a giant landscape puzzle of 500 pieces. For a while we only had 100 pieces. Now we have 100 more, and the picture is getting clearer."
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The Australian Federal Government released a report it commissioned from the Australian National University, showing global warming would push temperatures up by as much as 5.8 degrees by 2100. ...
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Although useful only ten hours a day and in only a few places, in desperation, power from changing tides would be possible. tidal power
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http://zfacts.com/p/379.html | 01/18/12 07:18 GMT
Modified: Mon, 26 Jun 2006 02:31:05 GMT
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