Stable Carbon Cycle–Climate Relationship During the Late Pleistocene

Science ^ | Nov 25, 2005 | Urs Siegenthaler

[plenipotentiary]

Stable Carbon Cycle–Climate Relationship During the Late Pleistocene Urs Siegenthaler,1 Thomas F. Stocker,1* Eric Monnin,1 Dieter Lüthi,1 Jakob Schwander,1 Bernhard Stauffer,1 Dominique Raynaud,2 Jean-Marc Barnola,2 Hubertus Fischer,3 Valérie Masson-Delmotte,4 Jean Jouzel4 A record of atmospheric carbon dioxide (CO2) concentrations measured on the EPICA (European Project for Ice Coring in Antarctica) Dome Concordia ice core extends the Vostok CO2 record back to 650,000 years before the present (yr B.P.). Before 430,000 yr B.P., partial pressure of atmospheric CO2 lies within the range of 260 and 180 parts per million by volume. This range is almost 30% smaller than that of the last four glacial cycles; however, the apparent sensitivity between deuterium and CO2 remains stable throughout the six glacial cycles, suggesting that the relationship between CO2 and Antarctic climate remained rather constant over this interval.

[plenipotentiary]

Top graph is CO2 variation over 650 thousand years

What this graph shows.

CO2 levels have been as high or higher than they are now four times in the last 400K years.

There is a regular pattern of rises and falls eight times over the last 650K years.

The most recent low point, 180 ppm was about 35K(thousand) years ago.

CO2 levels have risen steeply over that 35K year period, starting well before human civilisation, and about 35K years before any significant human intervention in the environment.

This graph shows conclusively that the CO2 levels at present are part of a long term trend pattern on which humans have had no input or effect.

It is clear that our worry for the next 30 thousand years is what we are going to do, if anything can be done, about the next ice age.

This graph is the end for the man made CO2 global warming theorists.

[Congressman Billybob]

Thank you for posting this. I love the smell of facts in the morning.

Congressman Billybob

Latest column: "51st Way to Leave Your Lover"

[satchmodog9]

But, but, but, it has to be Bush's fault.

[expatpat]

Thanks for a great post. I have alerted my lib friend already.

[Sam Cree]

*

[Unmarked Package]

Keep this data handy for rebuttal. The MSM (illegitimate media) will make a false connection between global warming and hurricanes which are increasing in frequency and intensity as a result of a naturally occurring, and completely unrelated, cycle of climatological events. All it takes to convince an uninformed populace is a few days of graphic video coverage of hurricane devastation together with a pretty-boy newscaster uttering the phrase "global warming". It's going to be a real battle to convince the masses that mankind is neither the cause or the cure for global warming and global atmospheric CO2 fluctuations.

[walford]

I knew as a 6th grader that the Earth has experienced extreme variances in climate. Some of these are cyclical. I'm certainly not arguing that there are no limits to what we should do to the environment, but to pretend that mankind has so much global influence in order to promote some sort of Luddite agenda is beyond dishonest.

[Jeff F]

CO2 levels have been as high or higher than they are now four times in the last 400K years.

Not really. The latest reading I could find was 376 ppm as of 2003 (see Mauna Loa). This is up from around 280 ppm in 1800 and well above the highest point shown in the historical graphic from the article.

I'm haven't made up my mind yet whether there is significant man made global warming. However, the recent CO2 data is pretty solid and does appear to be outside of the trends over hundreds of thousands of years.

[centurion316]

If you only read the MSM stories on this research, and did not see the graph, you would believe that scientists, whose knowledge, wisdom, and intellect cannot be challenged, had discovered beyond any doubt that CO2 levels were higher today than at any time in the last 650k years and that human activity was doubtless to blame.

And why does the media have a credibility problem?

[Names Ash Housewares]

And the Sun cycles on top of those.
It means we are are at mercy at forces far larger then anything we can think to have an impact on anytime soon.


http://www.swissinfo.org/sen/swissinfo.html?siteSect=511&sid=5080155

Sunspot activity hits 1,000-year high

“We have to acknowledge that the Sun is in a changed state. It is brighter than it was a few hundred years ago, and this brightening started relatively recently – in the last 100 to 150 years. We expect it to have an impact on global warming,” he told swissinfo.

Last week Solanki, who is a professor at the Federal Institute of Technology in Zurich, presented the findings at a conference of solar and stellar scientists in Hamburg, Germany.

His research team reached its conclusions after studying data from samples of ice collected by Swiss scientist Jürg Beer on an expedition to Greenland in 1991.

Most scientists acknowledge that greenhouse gases from fossil fuels have warmed the planet in past decades, but they have questioned whether a brighter Sun is also responsible for rising temperatures.

Global warming

Average global temperatures have increased by about 0.2 degrees Celsius over the past 20 years, and are widely believed to be responsible for new extremes in weather patterns across the world.

According to scientists, the Sun’s radiance has changed little during this period. But looking back over 1,150 years, Solanki found the Sun had never been as bright as in the past 60 years.

The indirect impact of more intense sunshine on the ozone layer and of solar activity on cloud cover may be affecting the climate more than the sunlight itself, he said.

“The change in solar brightness over the past 20 years is not enough to cause the observed changes in our climate. But the indirect effects may be larger, and the range of their influence is unclear, so more study is needed,” he added.

Sunspots

To see whether a brighter Sun is warming the planet, solar scientists have measured magnetic zones on the Sun’s surface, called sunspots.

Sunspots appear to intensify the Sun’s brightness and energy output, and their numbers are associated with climate, said Solanki, who is also managing director of the Max Planck Institute for Solar System Research in Germany.

Looking back over several hundred years, Solanki’s team found that not only did a dearth of sunspots signal a cold period – sometimes for as long as 50 years – but they also discovered that the number of sunspots increased over the past century as the Earth’s climate grew steadily warmer.

“All in all, I think we are coming to a point where we acknowledge that both solar activity and greenhouse gases are important factors in the change in the Earth’s temperature,” he said.

[Mike Darancette]

Not really. The latest reading I could find was 376 ppm as of 2003 (see Mauna Loa). This is up from around 280 ppm in 1800 and well above the highest point shown in the historical graphic from the article.

Maybe Mauna Loa has a higher level of CO2 than Antarctica, maybe the Antarctic data is misconstrued. And where does the 1800 data come from?

We collect 650,000 years worth of data by one method and compare it with 2 years of data collected by another method?

Does it make any different that Hawaii is a volcanic island and Mauna Loa is the world's largest and one of the world's most active volcanoes?

[plenipotentiary]

"The latest reading I could find was 376 ppm as of 2003"
Not apparently according to the ice core data. Mauna Loa data only goes back 50 years, the ice core goes back 650K years.
You are not comparing like with like are you?
Check this out: From Prof. Zbigniew Jaworowski http://www.warwickhughes.com/icecore/

This is why the records of CO2 concentration in the gas inclusions from deep polar ice show the values lower than in the contemporary atmosphere, even for the epochs when the global surface temperature was higher than now.
Figures 1A and 1B

The data from shallow ice cores, such as those from Siple, Antarctica[5, 6], are widely used as a proof of man-made increase of CO2 content in the global atmosphere, notably by IPCC[7]. These data show a clear inverse correlation between the decreasing CO2 concentrations, and the load-pressure increasing with depth (Figure 1 A). The problem with Siple data (and with other shallow cores) is that the CO2 concentration found in pre-industrial ice from a depth of 68 meters (i.e. above the depth of clathrate formation) was “too high”. This ice was deposited in 1890 AD, and the CO2 concentration was 328 ppmv, not about 290 ppmv, as needed by man-made warming hypothesis. The CO2 atmospheric concentration of about 328 ppmv was measured at Mauna Loa, Hawaii  as later as in 1973[8], i.e. 83 years after the ice was deposited at Siple.

An ad hoc assumption, not supported by any factual evidence[3, 9], solved the problem: the average age of air was arbitrary decreed to be exactly 83 years younger than the ice in which it was trapped. The “corrected” ice data were then smoothly aligned with the Mauna Loa record (Figure 1 B), and reproduced in countless publications as a famous “Siple curve”. Only thirteen years later, in 1993,  glaciologists attempted to prove experimentally the “age assumption”[10], but they failed[9].

Figure 2

The notion of low pre-industrial CO2 atmospheric level, based on such poor knowledge, became a widely accepted Holy Grail of climate warming models. The modelers ignored the evidence from direct measurements of CO2 in atmospheric air indicating that in 19th century its average concentration was 335 ppmv[11]

[fso301]

I think I need to bump and read this later

[PeaceBeWithYou]

Check this out, they rigged the icecore data too.

[Jeff F]

You are probably correct to point out that it is highly questionable to compare measurements taken by two completely different techniques. I don't know if the 280 ppm figure that is widely quoted is reliable. It is worthwhile to look at the direct measurements from Mauna Loa over the past 50 years:

Even assuming these readings are impacted by the proximity to an active volcano, you can't help but be struck by the clear and unbroken upward trend of the readings. All this while the volcanic activity has varied considerably.

Are you aware of any other modern CO2 direct readings that significantly differ from the Mauna Loa one in either magnitude or trend?

[TASMANIANRED]

Yeah, but they just ignore facts that interfere with their religion.

[plenipotentiary]

I think the point is that the atmospheric readings are calibrated one way, and the ice core readings another.
With the ice core results they take a sample and "estimate" how much CO2 was in the atmosphere. I suppose that over 650,000 years it's not so much the actual amount of CO2, but the pattern of fluctuation which is important.

You can't take 50 years worth of atmospheric data and say that the figures represent an unprecedented high for the last 650,000 years, cos we don't have atmospheric measurements for that length of time.

It will be interesting to find out by how many "years" the ice core people have jiggled the figures for their latest paper.

[truecons]

"It is clear that our worry for the next 30 thousand years is what we are going to do, if anything can be done, about the next ice age."

What we must do is equally clear: MAKE MORE CO2!!!

The chart indicates cycles that are phenominally consistent. Based on the last four cycles, we can predict that in the next 100 kyrs the CO2 level will plummet, and with it, the temperature (if we are to believe the global warming prophets' correlations).

It is therefore our duty as global citizens to immediately begin our program of CO2 replenishment by burning as much fossil fuel as possible, enjoying as high a standard of living as possible (thereby consuming more fossil fuels), and pouring billions of dollars into federally funded research to discover new ways to make as much CO2 as possible as soon as possible.

I'm being a little hyperbolic, but not by much...

[PeaceBeWithYou]

The only problems with that are:

1)Carbon Dioxide follows temperature rise instead of causing it. There is quite a bit of lag, (500-900 years).

2)Even if we wanted too, we couldn't inject enough Carbon Dioxide, Methane, or anything else, to stop an Ice Age.

3)The coming Ice Age will be Nature's show, not man's.

Given the lag, by the time the Global Community recognizes that Carbon Dioxide levels are falling it will be too late, as the temperature will have been 500(or more) years ahead of it.

[Junior]

Formatting is our friend.