[101voodoo]

"Not that global warming has much to do with actual science, but generally the people involved are trying to be scientifically accurate in their own way."

As the old saying goes, "Figures lie and liars figure"

[TheWasteLand]

I know nothing about ice cores and temperature measurement, but a quick google turned up this NASA link which you might find interesting:

Paleoclimatology The Ice Core Record

The relevant bit seems to be this:

"As with marine fossils, the ratio of oxygen isotopes in the snow reveals temperature, though in this case, the ratio tells how cold the air was at the time the snow fell. In snow, colder temperatures result in higher concentrations of light oxygen."

There is another article on the subject of oxygen isotopes:

Paleoclimatology The Oxygen Balance

[steelyourfaith]

 

Beam me to Planet Gore !

[metmom]

Maybe SunkenCiv could help?

[aruanan]

Go to CO2science.org and look at the index for this subject.

[Royal Wulff]

However, even in a super compacted state, like deep within a glacier, ice is still relatively porous and open to gas diffusion.

What is the basis for this statement? If it's so porous, why are any differences in concentration seen?

[SunkenCiv]

Antarctic Seafloor Core Suggests Earth’s Orbital Oscillations
May Be The Key To What Controlled Ice
Ohio State University | October 17, 2001
Posted on 10/18/2001 7:36:43 AM PDT by callisto
http://www.freerepublic.com/focus/f-news/551035/posts

[SunkenCiv]

Thanks Metmom.

· join · view topics · view or post blog · bookmark · post new topic ·

[stayathomemom]

I believe this topic is discussed in the book The Deniers, and it is as you suggest.

[Hoodat]

Ice core data is valid when making a comparison between different gases present. The Vostok samples have proven cyclical movement of temperatures (derived from O¹⁸ isotope) that nearly coincide with cyclical movement of CO₂ levels.

The problem lies when alarmists mix Antarctic ice core data from tens of thousands of years ago with North American atmospheric data taken today. There is no scientific validity in mixing both data sets. Atmospheric levels will naturally be higher because of diffusivity.

As for the causal relationship of CO₂ levels and temperature levels throughout the cyclical patterns of the ice core data over the last 600,000 years, the evidence shows that changes in CO₂ levels actually trailed changes in temperature. Thus higher temperatures lead to higher CO₂ levels, and not the other way around.