Environment - Nov 26
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Many more articles are available through the Energy Bulletin homepage
Rise in gases unmatched by a history in ancient ice
Andrew C. Revkin, NY Times
Shafts of ancient ice pulled from Antarctica's frozen depths show that for at least 650,000 years three important heat-trapping greenhouse gases never reached recent atmospheric levels caused by human activities, scientists are reporting today.
The measured gases were carbon dioxide, methane and nitrous oxide. Concentrations have risen over the last several centuries at a pace far beyond that seen before humans began intensively clearing forests and burning coal, oil and other fossil fuels.
The sampling and analysis were done by the European Program for Ice Coring in Antarctica, and the results are being published today in the journal Science.
(25 November 2005)
Many other stories have appeared about this study, inclduing in the LA Times.
Sea level rise doubles in 150 years
Ian Sample, The Guardian
· Increase blamed on fossil fuel use since 19th century
· Cut in greenhouse gases futile, researchers say
Global warming is doubling the rate of sea level rise around the world, but attempts to stop it by cutting back on greenhouse gas emissions are likely to be futile, leading researchers will warn today.
The oceans will rise nearly half a metre by the end of the century, forcing coastlines back by hundreds of metres, the researchers claim. Scientists believe the acceleration is caused mainly by the surge in greenhouse gas emissions produced by the development of industry and introduction of fossil fuel burning.
Today's warning comes from US researchers at Rutgers University in New Jersey who analysed cores drilled from different sites along the eastern seaboard. By drilling down 500 metres through layers of different sediments and using chemical dating techniques, the scientists were able to work out where beaches and dry land were over the past 100m years.
The analysis showed that during the past 5,000 years, sea levels rose at a rate of around 1mm each year, caused largely by the residual melting of icesheets from the previous ice age. But in the past 150 years, data from tide gauges and satellites show sea levels are rising at 2mm a year.
"The main thing that has happened since the 19th century and the beginning of the modern observation has been the widespread increase in fossil fuel use and more greenhouse gases," said Professor Kenneth Miller, who led the study. "We can say the increase we're seeing is much higher than we've seen in the immediate past and it is due to humans."
(25 November 2005)
I'm skeptical about the Guardian's sub-head saying: "Cut in greenhouse gases futile, researchers say." According to the story, only one researcher (Kenneth Miller) made that claim, and he said it in the context of Kyoto not being able to stop a rise in sea levels. Most of the analyses I've read maintain that reducing greenhouse gases is crucial to preventing the worst of the climate change scenarios. I looked at about six other articles that covered this story, and none of them mentioned this remark. Jon Lebkowsky at WorldChanging provides a clarification: Ice cores and climate change -BA
What's a boreal forest really worth?
Mark Hume, Globe and Mail
VANCOUVER -- How much is a forest worth if it's simply left standing instead of being logged and sent to a mill?
That question, in simple terms, is what researchers from the Pembina Institute set out to answer in a two-year study that calculated for the first time the "natural capital" contained in Canada's boreal forest ecosystem.
Considering everything from the pest-control services provided by birds to the worth of having peat lands filter drinking water, the researchers calculated the boreal forest ecosystem's non-market value at more than $93- billion annually.
In addition, the study found that the boreal forest, which reaches from Yukon to the Eastern Seaboard, works as a massive carbon sink. It stores an estimated 67 billion tonnes of carbon, the equivalent of 303 years of Canada's total 2002 carbon emissions. Considering the global effort to control carbon emissions, researchers said the boreal forest could be looked at like a "carbon bank account" worth $3.1-trillion (U.S.)
(25 November 2005)
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