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Scientists Fear Amazon May Face Early Destruction
By Trish Anderton
Researchers in the Amazon, attending the United Nations Conference on Climate Change in Bali, say a vicious cycle of climate change and deforestation could destroy the world's largest tropical rain forest more quickly than expected. Trish Anderton explains, in a background report.
Researcher Dan Nepstad calls it a "perfect storm" of deforestation: as fire and ranching destroy the Amazon forest in Brazil, the remaining trees release less moisture, producing a dryer climate that kills more trees. It adds up to a vicious cycle of destruction.
A World Bank-funded study released early this year predicted the Amazon could become a grassy savannah by the end of the century. Nepstad produced a report for the World Wildlife Fund or WWF that was released at the Bali climate change conference. He says substantial destruction could come much sooner than that. "If we add these processes up, we see that by 2030 - not by the end of the century but in the next two and a half decades - given current trends, 55 percent of the forests of the Amazon will have been cleared or impoverished through some combination of logging, drought and fire," said Nepstad.
Amazon carbon sink effect 'slows'
Scientists have sounded the alarm after spotting changes in the environment in Brazil's tropical rain forests. They say they have found worrying signs that the forests may become less able to absorb the carbon dioxide emissions blamed for global warming. Their long-term study in supposedly pristine areas reveals trees have been growing and dying faster than before.
Fact: Amazon forest contains 20% of the worlds CO2
CO2 Rocketing, Carbon Sinks Failing
23 October 2007 Man's activities are releasing carbon dioxide faster than ever, while the natural processes that normally slow its build up in the atmosphere appear to be weakening, suggests a new study in the Proceedings of the National Academy of Sciences. The report states that "together, these effects characterize a carbon cycle that is generating stronger-than-expected climate forcing sooner than expected."
Rainforests are home to probably 50 percent of the world's species, making them an extensive library of biological and genetic resources. In addition, rainforests help maintain the climate by regulating atmospheric gases and stabilizing rainfall, protect against desertification, and provide numerous other ecological functions. However, these precious systems are among the most threatened on the planet. Although the precise area is debated, each day at least 80,000 acres (32,300 ha) of forest disappear from Earth. At least another 80,000 acres (32,300 ha) of forest are degraded. Along with them, the planet loses as many as several hundred species to extinction, the vast majority of which have never been documented by science. As these forests fall, more carbon is added to the atmosphere, climactic conditions are further altered, and more topsoil is lost to erosion.
Forests Are Not GreenThe Amazon may not help in the battle against rising temperatures.
Tinder: The Amazon is vulnerable to fire By Mac Margolis | NEWSWEEK Dec 10, 2007 Issue
What does climate change sound like? "Usually when you walk through the rain forest you hear a squishy sound from all the moist leaves and organic debris on the forest floor," says ecologist Daniel Nepstad, a researcher at the Woods Hole Research Center and longtime scholar of the Amazon rain forest. "Now we increasingly get rustle and crunch. That's the sound of a dying forest." Left alone, it was assumed, the world's rain forests would not only flourish but might even rescue us from greater folly by sopping up the excess carbon dioxide and other planet-warming greenhouse gases. Now it turns out that may be wishful thinking. Some scientists believe that the rise in carbon levels means that the Amazon and other rain forests in Asia and Africa may go from being assets in the battle against rising temperatures to liabilities. Amazon flora, for instance, holds more than 100 billion metric tons of carbon, equal to 15 years of tailpipe and smokestack emissions. If the collapse of the rain forests speeds up dramatically, it could eventually release 3.5 billion to 5 billion metric tons of carbon into the atmosphere each year—making forests the leading source of greenhouse gases.
· Global warming causing plants to lose CO2 rather than absorbing it in northern regions · · North America ‘overwhelmed’ by human-caused emissions
Warming autumn enhancing carbon loss from terrestrial ecosystems
Scientists Startled By Speed of Change in New England Forests Trees are responding to warming in New England much faster than expected
The Boston Globe, March 17, 2008 HUNTINGTON, Vt. - After about a mile of snowshoeing up Camels Hump mountain, University of Vermont ecologist Brian Beckage paused to take in the trees around him - not just for their beauty, but for the dramatic change they appear to be undergoing because of climate change. Forty years ago, this part of the mountain would have been blanketed with cold-loving red spruce and balsam fir trees. But today, warmer-loving northern hardwoods such as sugar maples and American beech are taking over. Scientists have long thought it would take generations if not centuries for tree populations to shift in response to a warming world. But Beckage and his colleagues' work on Camels Hump and two other nearby mountains suggests that climate change might affect New England forests far sooner than scientists thought. "The fact that we found shifts here may be indicative that forests are changing throughout the region," he said.
Canada's boreal forest a ticking 'carbon bomb': report
Updated Thu. Apr. 10 2008 11:21 AM ET The Canadian Press OTTAWA -- Canada's boreal forest is a ticking "carbon bomb" and its continued logging could trigger a massive release of greenhouse gases, says a new report. A Greenpeace study released Thursday says cutting down trees in the boreal forest is exacerbating climate change by releasing stores of greenhouse gases trapped in soil and vegetation. It also found that logging makes the forest more susceptible to insect outbreaks and wildfires which, if widespread, could cause a spike in greenhouse-gas emissions - the so-called "carbon bomb." And the report says a warmer climate melts permafrost, releasing methane, a greenhouse gas 21 times more potent than carbon dioxide. "The idea is that if the current trends continue ... what could happen is a sudden and massive release of greenhouse gases from the forest caused by a rapid outbreak of forest or peat fires," said Greenpeace's Christy Gerguson.
Canada's boreal forest stores 186 billion tonnes of carbon dioxide, the report says - about 27 times the world's yearly fossil-fuel emissions.
Wildfire Drives Carbon Levels In Northern ForestsScienceDaily (Nov. 5, 2007) — Far removed from streams of gas-thirsty cars and pollution-belching factories lies another key player in global climate change. Circling the northern hemisphere, the conifer-dominated boreal forests - one of the largest ecosystems on earth - act as a vast natural regulator of atmospheric carbon levels. The group found that the effects of carbon dioxide and climate - temperature and precipitation - varied from year to year but generally balanced out over time and area. Instead, forest fires during the 60-year period had the greatest direct impact on carbon emissions from the system. However, "because fire frequency and fire intensity are directly controlled by climate change, it doesn't mean that we shouldn't be focusing on climate change," Gower says. "Climate change is what's causing the fire changes. They're very tightly coupled systems." The earth’s boreal forests, which are one of the largest ecosystems on the planet, play a key role when it comes to global climate change; the boreal forests act as a natural regulator of a atmospheric carbon levels. The boreal forests are second in size only to the tropical rainforests
and form a green band that spans the higher latitudes of Canada, Alaska,
Siberia, China, and Scandinavia. Historically, scientists believe the boreal forest has acted as a carbon sink, absorbing more atmospheric carbon dioxide than it releases, Gower says. Their model now suggests that, over recent decades, the forest has become a smaller sink and may actually be shifting toward becoming a carbon source.
http://www.sciencedaily.com/releases/2007/10/071031152918.htm
Global Warming is Wreaking Havoc in Canada's Forests with Pine Beetle Infestation
Rapid Warming' Spreads
Havoc in Canada's Forests
By Doug Struck
QUESNEL, B.C. -- Millions of acres of
Canada's lush green forests are The mountain pine beetle has infested an area three times the size of
"It's pretty gut-wrenching," said Allan Carroll, a
research scientist at the
Winter did not stop pine beetle spread in Alberta
Thu Jun 26, 2008 5:56pm EDT
VANCOUVER, British Columbia (Reuters) - Cold temperatures did not stop the spread of pine beetles in Alberta this winter, and it may be too late to eliminate the tree-killing insects from the province, officials said on Thursday. Cold winter temperatures slowed the growth of the beetle population in parts of the province, but a survey this spring indicates thousands survived in much of southwestern Alberta and in pockets elsewhere. "Pine beetles may be here to stay in Alberta," Sustainable Resource Development Minister Ted Morton said in a written statement.
Boreal releasing more GHGs than it absorbs: study
Updated Wed. Oct. 31 2007 6:41 PM ET The Canadian Press A new study suggests Canada's boreal forest may be releasing more greenhouse gases than it absorbs.
Fact: the boreal forest alone stores 186 Billion tons of CO2. That is the equivalent to 27 years of the world’s carbon dioxide emissions from burning gas and oil and heat.
May 2, 2007 (Runs 14:27) CBC News Trillions of pine beetles are devouring British Columbia's forests and heading east. Margo McDiarmid reports on one of the first visible effects of climate change in Canada.
Is there hope for the world's vanishing forests? The global rate has slowed, but deforestation still rapid in many countries
Study suggests trees dying due to global warming
January 22, 2009 THE CANADIAN PRESS An extensive new study has found that trees in old-growth forests across western North America are dying faster than they can grow back and that climate change is probably the cause. The conclusion raises questions about how forests are responding to global warming and raises fears that decomposing trees could become another source of greenhouse gases, said Lori Daniels, one of the co-authors of the paper that appeared Thursday in the journal Science. "This study is providing, certainly circumstantial and consistent evidence, that regional warming is having impacts on our forests," she said. "These trees are stressed and are susceptible.
Climate change news
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