Title: [GreenYes] Re: FW: new IPCC Climate Report
I think that there are many ways of looking at greenhouse gases, but
that the 100 year timeframe is a good one. We can look at the impact
of greenhouse gases in different timeframes, but many of us are most
worried about what sort of a world we are handing down to future
generations, not the immediate impact in the present. Methane
emissions generally affect present generations but methane emitted
today has relatively little impact on future generations. In
contrast, carbon dioxide emitted now has a significant impact on
future generations, since it is so stable and long-lived in the
I know that methane in the atmosphere is oxidized to carbon dioxide
and water. According to the Wikipedia article on methane, the half-
life of methane in the atmosphere is about 7 years. This means that
for methane emitted today, only 1/8 of that methane will still be in
the atmosphere 21 years (roughly 1 generation) from now. By 100
years, virtually all of the methane will be gone, with only 1 part in
20,000 still remaining. Because methane is so potent of a greenhouse
gas though, even looking at it averaged out over a 100 year time frame
still results in it being some 23 times more potent than CO2.
However, the methane we are emitting today will have relatively little
impact on the world that my grandchildren's potential children (if
they have any) will see.
Oregon Department of Environmental Quality
On Oct 11, 1:49 pm, "Eric Lombardi" <e...@no.address> wrote:
> Hi all,
> This is bad news. but check out this one statement: "Flannery, named
> Australian of the Year for 2007. says that higher figure is due to
> miscalculating the potency of other greenhouse gasses, which are included in
> the 450 ppm figure and measured in terms equivalent to that of CO2.
> That sounds like methane to me. and this issue of "impact" from GHG gas
> other than carbon needs to be better understood.
> Here is my understanding of what has happened, and if I'm wrong, please
> someone correct me. The IPCC decided that since "carbon" hangs out in the
> atmosphere to do it's dirty work for 100 years, then the two other major
> GHG's (methane and nitrous oxide) would be "normalized" to have their
> impacts also spread out over 100 years. even if that isn't true. And, it's
> not true. Methane actually does the bulk it's dirty work as a GHG within 20
> years, not 100. We've all heard that methane is 23 times more effective as
> a GHG than carbon, but that is using the 100-year impact timeline.
> According to a paper out of Israel done a few years ago, if you really
> measure the actual impact of methane over it's 20 year impact period, it is
> actually 56 times more impactful than carbon!!! The Israeli paper
> concluded that landfill gas accounted for 25% of that nation's GHG impact,
> and that the most powerful and cost-effective step they could take to reduce
> GHG impacts for the nation would be to immediately stop burying
> biodegradable trash. Now, compare that with our own EPA WARM model that
> says landfill gas is only 3% of the problem. No wonder Waste Management
> Inc. supports the use of WARM as a tool for analyzing "waste and GHG
> issues". I was always suspicious of that endorsement, and now I know why.
> Sounds to me like this guy Flannery is discovering what the Israeli's
> already knew . that the IPCC and everybody else has been UNDER COUNTING the
> impact of methane as a GHG, and thus understating the impact that landfills
> are having on global warming. Peter Anderson has been saying this for
> years . it is time that we pull this all together and get the facts out .
> and then STOP LANDFILLING BIODEGRADABLE MATERIALS.
> <http://www.csmonitor.com/> csmonitor.com - The Christian Science Monitor
> from the October 11, 2007 edition
> A key threshold crossed
> An Intergovernmental Panel on Climate Change report to be released next
> month will show that the limit on greenhouse-gases scientists hoped to avert
> has already been surpassed.
> E1EDE2&url="" Gregory M. Lamb
> In Ray Bradbury's science fiction novel "Fahrenheit 451," that number
> represented the temperature at which books would burn, a symbol of a
> disturbing future under a totalitarian government.
> For climate scientists, a similar number, 450 parts per million (ppm), holds
> its own ominous meaning. It represents a dangerous concentration of
> greenhouse gases in the atmosphere; a total that they were not expecting to
> be passed for at least another decade.
> But a new UN-sponsored report, to be released next month, will show that as
> of 2005 the concentration of greenhouse gases in the atmosphere had already
> reached 455 ppm, according to Tim Flannery, a prominent Australian climate
> scientist who says he's seen the raw data that go into the document.
> In an interview on Australian television this week, Dr. Flannery said that
> an Intergovernmental Panel on Climate Change (IPCC) report will show that
> carbon dioxide (CO2), nitrous oxide, methane, hydrofluorocarbons (HFCs), and
> other <http://uk.reuters.com/article/oilRpt/idUKSYD29548220071009>
> greenhouse gasses are at much higher concentrations than previously thought.
> Reuters quotes him:
> "We thought we'd be at that threshold within about a decade.... We thought
> we had that much time. But the new data indicates that in about mid-2005 we
> crossed that threshold.... What the report establishes is that the amount of
> greenhouse gas in the atmosphere is already above the threshold that could
> potentially cause dangerous climate change."
> About 75 percent of the total ppm represents carbon dioxide, associated with
> burning fossil fuels. The rest is a combination of the other gasses, he
> On the Sierra Club website, blogger Pat Joseph explains
> <http://www.sierraclub.org/compass/2007/10/fast-track-to-ruin.asp> the
> meaning of 450 ppm:
> "450 ppm has long been held up as the threshold we dare not cross if we hope
> [to] avert the worst consequences of warming. Well, if Flannery is right,
> (and there's no reason to think otherwise) we crossed that line without even
> breaking stride."How did it happen? For one thing, countries such as China
> and India are actually "recarbonizing," Mr. Joseph says, meaning that their
> economies are becoming more energy-intensive "as they turn increasingly to
> [greenhouse-gas emitting] coal to feed their growth."
> <http://news.bbc.co.uk/2/hi/science/nature/6620909.stm> In May, the IPCC
> estimated current concentration of greenhouse gases at only 425 ppm, said a
> BBC report at the time. It noted that many scientists equated 450 ppm with a
> 2 degree C (3.6 degrees F.) rise in temperatures. Allowing temperatures to
> rise more than 2 C could lead to major impacts on the environment,
> scientists said. In the article, Rajendra Pachauri, the chairman of the
> IPCC, explained the strategy this way:
> "If you want to stabilise around 450 ppm, that means in a decade or two you
> have to start reducing emissions far below the current level.... So in other
> words, we have a very short window for turning around the trend we have in
> rising greenhouse gas emissions. We don't have the luxury of time."
> But, says Flannery, named Australian of the Year for 2007, that window is
> closed. According to the Australian Associated Press he says that higher
> figure is due to miscalculating the potency of other greenhouse gasses,
> which are included in the 450 ppm figure and measured in terms equivalent to
> that of CO2. But he adds:
> e%20rate%20of%20accumulation%20of%20co/> we have really seen an unexpected
> acceleration in the rate of accumulation of CO
> 2007/10/09/1191695858995.html> 2 itself, and that's been beyond the limits
> of projection ... beyond the worst-case scenario. We are already at great
> risk of dangerous climate change - that's what the new figures say.... It's
> not next year, or next decade; it's now."
> A major UN climate change meeting in Bali, Indonesia, in December aims to
> set a course toward a new global agreement to reduce greenhouse-gas
> emissions. The current Kyoto Protocol, signed by the majority of the world's
> nations but not the United States, expires in 2012. Flannery told Reuters
> that the 450 ppm figure adds to the urgency and importance of that meeting.
> Meanwhile, Erwin Jackson, policy director of the Climate Institute, an
> Australian environmental group, told the Australian Associated Press that
> <http://www.news.com.au/story/0,23599,22558145-29277,00.html> reducing
> greenhouse gas levels would be the only path to avoiding a catastrophe:
> "The longer we stay above the kind of levels we're at at the moment, the
> more likely it is that we would start to see the loss of the Great Barrier
> Reef; you would actually start see the collapse of the great ice sheets and
> places like the Amazon starting to burn down."