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"Carsten Troelsgaard" <carstenNOSPAM.troelsgaard@xxxxxxx> wrote in message
news:44018a5d$0$47008$edfadb0f@xxxxxxxxxxxxxxxxxxxxxxx
>
> "Alastair McDonald" <alastair@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> skrev
> i en meddelelse news:dtptm7$gv0$1@xxxxxxxxxxxxxxxxxxxxxxx
> > "SBC Yahoo" <atilla.the.hun@xxxxxxxxxxxxxxxxx> wrote in message
> > news:S3MLf.60122$PL5.48562@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> >> Yes, it has climbed since the 1950's, all right. However, what units of
> >> measurement were they using which were noted as ppm(v)? I have never
> >> heard
> >> of this unit of measurement. ppm is usually parts per million parts of
> >> weight. But the "v" would indicate to me that it may be volume, in which
> >> case one set of studies is giving parts per million in volume, the other
> >> in
> >> weight. (http://cdiac.esd.ornl.gov/trends/co2/graphics/vostok.co2.gif)
> >
> > On that .GIF, the y-axis is CO2 Condentration (ppmv)
> >
> > At cdiac.ornl.gov/ftp/trends/co2/sposio.co2">http://cdiac.ornl.gov/ftp/trends/co2/sposio.co2 ,
> > one of the links I gave you for CO2 at the South Pole, it says that
> > the measurements are in ppmv viz.
> > *** Atmospheric CO2 concentrations (ppmv) derived from flask ***
> > *** and in situ air samples collected at the South Pole ***
> >
> > There is no point in you denying the facts. Since the Industrial
> > Revolution atmospheric CO2 has increased from 280 ppmv to 380 ppmv.
> >
> >> In any event, there is no doubt that the conc. of CO2 is increasing, but
> >> look at the long picture, it has done this four times in the past and man
> >> was not around. Each time it returned to a low range after a period of
> >> time
> >> (50,000 years). The earth's time is different from man's time. On the
> >> earth clock, a billion years is but an hour.
> >
> > The four times in the past to which you refer, were when the Earth
> > was warming due to it exiting a glacial period. We are no longer
> > in a glacial period, hence the reason for the CO2 increasing can
> > not be due to that. From a geological point of view 380 ppm of CO2
> > is not exceptional, but from the POV of mankind it certainly is.
> > I am sure that Earth will laugh of such a small change, but it may
> > also laugh mankind off its face. Don't forget we have evolved to
> > survive a range of 180 to 280 ppm. What the effects of 380 ppm are
> > unknown.
> >
> >> I would say we do not want to put any more co2 into the atmosphere than
> >> we
> >> have to, but it is not the most important thing that we face, by any
> >> stretch
> >> of the imagination.
> >
> > How do you know that it is not important. It seems that the increase in
> > CO2
> > is melting the Greenland ice sheet, and that will lead to sea levels
> > rising
> > by over 20 feet, flooding every port in the world, many of which like New
> > York and London are major cities. We are not talking about losing the Twin
> > Towers. We are talking about losing every skyscraper in New York!
>
> I've just had a snap look for sources showing the overall ice-budget of
> Greenland and Antarctic without finding it. The current melting is a coastal
> phenomena leaving the inner reaches still building up snow-cover.
> See ie..W.S.B. Paterson, "The physics of glaciers" 3. ed. 1994
> Some altimetry-measurements by flight or satelite should have been conducted
> since.
Here is a link to the more recently published work.
www.eurekalert.org/pub_releases/2005-11/esa-eas110405.php">http://www.eurekalert.org/pub_releases/2005-11/esa-eas110405.php
It implies that there is no need to panic because the central ice
cap will grow until the temperature is 3C higher.
However, even more recent than that (also published in Science) is
described here;
New Study in Science Warns of Greenland's Accelerating Glaciers
www.aaas.org/news/releases/2006/0216ice.shtml">http://www.aaas.org/news/releases/2006/0216ice.shtml
What Jim Hansen is saying (see my previous post) is that the models
are too simple. What I am saying is that the melting around the
margins of the Greenland ice sheet is already accelerating, therefore
we have already reached the tipping point. Unless we reduce the
CO2 levels or do something else to cool the planet, then the melting
of the Greenland ice will speed up and it will soon become a total
loss.
Cheers, Alastair.
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