Replies

The climate sensitivity to increasing CO2 is the important factor, not the direct heating contribution of CO2.

There is no measurable climate sensitivity to increasing CO2 if there were, the average surface temperature of the earth in the following graphical presentation would have a curve similar to the CO2 curve.

Global Surface Temperature and Atmospheric CO2 over Geologic Time

Late Carboniferous to Early Permian time (315 mya -- 270 mya) is the only time period in the last 600 million years when both atmospheric CO2 and temperatures were as low as they are today (Quaternary Period ).

Temperature after C.R. Scotese
CO2 after R.A. Berner, 1994

There has historically been much more CO2 in our atmosphere than exists today. For example, during the Jurassic Period (200 mya), average CO2 concentrations were about 900 ppm or about 2.5 times higher than today. The highest concentrations of CO2 during all of the Paleozoic Era occurred during the Ordovician Period, exceeding 6000 ppm -- more than 16 times higher than today.

The Carboniferous Period and the Ordovician Period were the only geological periods during the Paleozoic Era when global temperatures were as low as they are today.

To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age, with CO2 concentrations nearly 15 times higher than today-- 5500 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.

We've been over this before

Yep, and I sure we will go over it again.

and I've posted the Hansen forcing diagram in response, but you keep regurgiposting the same stuff.

Why should the information change? What exists in the paleoclimatic record doesn't change merely for ones convenience or Hansen's forcing diagram; nor do the studies on CO2/Temp correlation and causality change from one month to the next. They are as applicable today as they have always been in defeating the base presumption built into the IPPC's models of CO2 "forcing" (i.e driving) atmospheric temperature.

The same stuff, is applicable, Hansens forcing curve is based in the same erroneaous presumptions of a "runaway" greenhouse, for which there is no basis as can be seen in the prior chart. The earth's temperature across the last billion or more years is self limiting and is clearly not a a function of atmospheric CO2 concentrations.

It's somewhat pointless to try and discuss this with you when you post outdated information (such as the 0.04C/decade caption to your first figure)

Not outdated at all, the link is current and the data set is complete to 2003, anyone may run the regressions on the data set to compute the results of 0.04C/decade through Feb 2002, with 0.07C/decade by adding in the data including the final el-nino even after Feb 2002. The web page linked by the way is the Current NASA page for the MSU graphic, and links to current dataset.

and you continue posting propaganda pieces.

So data contrary to your view of things is characterised by you as propoganda. Sorry, doesn't fly.

Now that the trend is definitely upward, we hear that the record isn't long enough to be significant or that it's less than expected.

What trend? There is no more than a short term raw dataset with a regression which is just as likely to change the other way in another 10-20 years data input.

The only upward overall trend on multi century basis is that of a natural tendency to the mean of the current era, not one measurably driven by any activity of mankind.

It is also abundantly clear we are in a multi-millenial down trend from somewhat higher temperatures earlier in a much older glacial cycle.

. Everybody knows that water vapor is the dominant greenhouse gas; if it wasn't the Earth would be an uninhabitable -40 C world. BFD.

Casual dismissal of the variation in water vapor as a contributor of climate variation is hardly useful to the discussion, considering the fact that loss of water vapor in the atmosphere is one of the primary factors in deepening the earth's glacial cycle. "BFD" indeed.

The key is the forcing effect of the CO2 being added to the atmosphere,

Tch,tch, from whence this CO2 being added? warming of the oceans by solar activity, changes in earths orbit increasing bio activity and biomass, as well as release from CO2 trapped in ice, & solution in oceans. But more importantly increases in water vapor in much higher measure as a concequence of ocean warming.

which in turn increases relative humidity (water vapor, of course) and has additional positive feedback effects.

Kind backward in your causation I do believe.

Global warming and global dioxide emission and concentration:
a Granger causality analysis
http://isi-eh.usc.es/trabajos/122_41_fullpaper.pdf

"We find, in opposition to previous studies, that there is no evidence of Granger causality from global carbon dioxide emission to global surface temperature. Further, we could not find robust empirical evidence for the causal nexus from global carbon dioxide concentration to global surface temperature."

Regarding the time lag between warming and CO2 levels. I think we've been over this before, but due to the reservoir of dissolved CO2 in the surface ocean, there's no doubt that warming due to astronomical factors would definitely cause a CO2 increase.

It's also a positive feedback mechanism:

There is no "positive feedback" the only energy input is solar, change in concentration of atmospheric gasses can only shift the absorption spectum but cannot create heat where there is none to begin with.

There is no runnaway effect whatsoever, in fact the effectiveness of atmospheric heat retention decreases exponentially with increasing concentration of water vapor and lesser greenhouse gasses, that is why the earth's surface temperature limits out at approximately 22^oC of solar input instead of continual rise above that level that a supposed positive feedback, "runnaway" greenhouse scenario demands.

once higher C02 concentrations are in place, they contribute to the maintenance of a warmer climate, DUE to their radiative forcing contribution.

A presumption unsupported in paleoclimatic studies of causality.

Here Comes the Sun

"Carbon dioxide, the main culprit in the alleged greenhouse-gas warming, is not a "driver" of climate change at all. Indeed, in earlier research Jan Veizer, of the University of Ottawa and one of the co-authors of the GSA Today article, established that rather than forcing climate change, CO2 levels actually lag behind climatic temperatures, suggesting that global warming may cause carbon dioxide rather than the other way around."
***
"Veizer and Shaviv's greatest contribution is their time scale. They have examined the relationship of cosmic rays, solar activity and CO2, and climate change going back through thousands of major and minor coolings and warmings. They found a strong -- very strong -- correlation between cosmic rays, solar activity and climate change, but almost none between carbon dioxide and global temperature increases."

Nor is positive feedback/ runnaway greenhouse supported by the paleoclimatic record of CO2 concentration vs temperature represented in the first graphic above.

The problem is, we're in a relatively stable climate regime, with no indications of astronomical warming/cooling factors

Sorry, bad assumption:

Red Planet Warming;
Global Warming on Triton (Neptune's moon)
(and anyway, they act on a much longer time scale than one or two centuries).

Your opinion is not support by the paleoclimatic data, nor by correlations with known astrophysical perturbations of solar irradiation of the earth on millenial scales, as the actual changes from iceage to interglacial period and back are quite swift due to the actual external factors impacting the absorption of solar energy by the earth.

The issue is not so much one of variation of solar output, as it is the variation of the earth's ability to reflect solar radiation; mainly affected by reflection of high altitude cloud formations impacted by astrophysical effects of earth's path through space(both orbital)

Origin of the 100 kyr Glacial Cycle
by Richard A. Muller

Figure 2. Spectral fingerprints in the vicinity of the 100 kyr peak: (a) for data from Site 607; (b) for data of the SPECMAP stack; (c) for a model with linear response to eccentricity, calculated from the results of Quinn et al. (ref 6); (d) for the nonlinear ice-sheet model of Imbrie and Imbrie (ref 22); and (e) for a model with linear response to the inclination of the Earth's orbit (measured with respect to the invariable plane). All calculations are for the period 0-600 ka. The 100 kyr peak in the data in (a) and (b) do not fit the fingerprints from the theories (c) and (d), but are a good match to the prediction from inclination in (e). return to beginning

Far more important to our present analysis, however, is the fact that the predicted 100 kyr "eccentricity line" is actually split into 95 and 125 kyr components, in serious conflict with the single narrow line seen in the climate data. The splitting of this peak into a doublet is well known theoretically (see, e.g., ref 5), but in comparisons with data the two peaks in the eccentricity were merged into a single broad peak by the poor resolution of the Blackman-Tukey algorithm (as was done, for example, in ref 8). The single narrow peak in the climate data was likewise broadened, and it appeared to match the broad eccentricity feature.
***
Figure 3. Variations of the inclination vector of the Earth's orbit. The inclination i is the angle between this vector and the vector of the reference frame; Omega is the azimuthal angle = the angle of the ascending node (in astronomical jargon).. In (A), (B), and (C) the measurements are made with respect to the zodiacal (or ecliptic) frame, i.e. the frame of the current orbit of the Earth. In (D), (E), and (F) the motion has been trasformed to the invariable frame, i.e. the frame of the total angular momentum of the solar system. Note that the primary period of oscillation in the zodiacal frame (A) is 70 kyr, but in the invariable plane (D) it is 100 kyr.

(and through dust of the galactic spiral)

Shaviv and climatologist Ján Veizer of Ruhr University, Germany, reckon that the spiral arms of our galaxy hold the secret to the Earth's see-sawing climate. Every 150 million years, blasts of cosmic rays cool the planet on its stately passage through the cosmos, they argue₂.
Cosmic rays thrown out by dying stars in the dust-rich arms of the Milky Way increase the number of charged particles in our atmosphere. There is some evidence that these may encourage low-level clouds to form, which cool the Earth.
Shaviv and Veizer have created a mathematical model of the number of cosmic rays hitting our atmosphere. They compared its predictions with other researchers' estimates of global temperatures and carbon dioxide levels over the past 500 million years.
They conclude that cosmic rays alone can account for 75% of the change in global climate during that period, and that less than half of the global warming seen since the beginning of the twentieth century is due to greenhouse gases.

Partly because more significant detrimental ecosystem effects are expected to happen when global temperature rises more than about 2.5 C.

Fortunately there is no substantive basis to presume that we are headed for 2.5^oC. The IPPC's modelling is based in fallacious presumptions,

http://www.pacificresearch.org/pub/cap/2003/cap_03-02-20.html

"The Economist, which provides the best environmental reporting of any major news source, carried a small story last week about a simple methodological error in the latest U.N. global warming report that has huge implications. The article, "Hot Potato: The Intergovernmental Panel on Climate Change (IPCC) Had Better Check Its Calculations" (February 15 print edition), reviews the work of two Australian statisticians who note an anomaly in the way the IPCC estimated world carbon dioxide emissions for the 21st century."
......
"The IPCC's method has the effect of vastly overestimating future economic growth (and, therefore, CO2 emissions) by developing nations. The fine print of the IPCC's projections, for example, calls for the real per-capita incomes of Argentina, South Africa, Algeria, Turkey, and even North Korea to surpass real per-capita income in the United States by the end of the century. Algeria? North Korea? The IPCC must be inhaling its own emissions to believe this."

and the models themselves cannot even predict actual measurements. Looking outside the computer models for confirmation of their inputs & output, confirmation fails.

Global Warming Score Card

There is more than sufficient room for doubt as to any negative effect human created CO2, may have on our Climate future.

I want to initially concentrate on one point.

Tch,tch, from whence this CO2 being added? warming of the oceans by solar activity, changes in earths orbit increasing bio activity and biomass, as well as release from CO2 trapped in ice, & solution in oceans. But more importantly increases in water vapor in much higher measure as a concequence of ocean warming.

Are you SERIOUSLY suggesting that the increase in CO2 concentrations in the atmosphere is NOT anthropogenic? Please indicate if you maintain a) the majority of CO2 added to the atmosphere since 1850 is from human sources, primarily fossil fuels, or b) the majority of CO2 added to the atmosphere since 1850 is not anthropogenic.

I have to find out if you're credible on this point or not.

Responding to little things:

So data contrary to your view of things is characterised by you as propoganda. Sorry, doesn't fly.

I was referring to the OISM hoax survey in this case. I'm glad you didn't post that tripe again.

I apologize for "thinking out loud" in your presence, but with my background this note intrigued me:

To the consternation of global warming proponents, the Late Ordovician Period was also an Ice Age, with CO2 concentrations nearly 15 times higher than today-- 5500 ppm. According to greenhouse theory, Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence earth temperatures and global warming.

The reason that I'm thinking out loud is that something we'll return to repeatedly as we consider paleoclimate evidence is the apples-to-oranges comparison trap -- a trap that I'd like to avoid. If we are going to figure out what is happening now and what might happen in the future, we have to make sure that what we are considering is relevant. OK -- there's no doubt that "other factors besides atmospheric carbon [dioxide] influence earth temperatures and global warming". The rate of plate tectonics is a first-order driver over millions of years (something Berner, whom you cite, has studied extensively). But if we are considering climate changes over millenial or shorter timescales, then considering plate tectonic processes is pretty useless. I hope you agree with that.

Having said that, what is known about the Ordovician paleoclimate? Here's a good description, from my Cal-Berkeley friends:

Ordovician: Tectonics and Paleoclimate

Read it at your leisure. Summary: continents were moving around, mountains were rising, ocean currents were totally different tha today, eventually Gondwanaland made it to the South Pole when the Ashgillian glaciation took place. You know how long the Ashgillian was? About 10 million years. All of the Pleistocene glaciations took place in less than 0.5 million years.

So does the fact that CO2 was much, much higher in the Ordovician, when there was an Ice Age, cause me consternation? Not a bit. Because this is an apples-to-oranges comparison; it's virtually meaningless and it does not instruct us regarding processes that are relevant today. Because I know that there are other factors that affect Earth's climate other than CO2, particularly when the timescales under discussion differ by several orders of magnitude. It's also apples-to-oranges in terms of the overall climate setting, i.e., where the continents were, where the ocean currents where, where the continental shelves were, what the ocean chemistry was (note the end of the second paragraph on the linked page), etc.

But there is still an important question regarding whether or not CO2 was a paleoclimate factor. I'll get to that next week. This will be the last post for today and the weekend, but I'll be working on next week's submission in the interim.

Thank you both for your posts to this thread.

For what it is worth, AG - I'm with you on this. There simply is not sufficient evidence to support the viewpoint that significant danger is posed to the planet by mankind's meager contribution to "greenhouse gasses" and supporting a radical change in our economy. In fact, I lean toward the viewpoint that we should welcome whatever warming we are able to affect ... which appears small at best - and possibly that in the future we may wish we could affect it in a far more substantial manner to alleviate a coming Ice Age.

Nevertheless, cog: I honestly do appreciate your contribution to these discussions and your point of view is enlightening and welcome.

I will state again: when the satellite data support the contention that global temperatures are on a major increase and that such an increase is not due to increased solar activity, I'll start to be concerned that there _may_ be something we need to do something about. There is NO such evidence ... and the last thirty years of the best data we have been able to get do not change that. Recall that EVERYONE was claiming the satellite data WOULD be the best temperature data we could get, until one side found their position was not supported by that data ... now they have to find a way around that major anamoly.