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Monbiot puts up prize for best online denial rubbish - Page 3

post #61 of 119
Quote:
Originally Posted by AlTekhasski View Post

Could you both please be a little more specific about which other "various feedbacks" you are talking about, the ones that have not reached their strength yet?
 

See the Climate Sensitivity Wiki.
post #62 of 119
I asked "which other various feedbacks" you could suggest, and already excused the ice albedo and water vapor. The rest of your listed feedbacks produce CO2, which we already know from current observations de facto.

From your brevity I must deduce that you have nothing to put forth, and therefore there should be no essential (or even hypothetical) differences between the modern observation of global {CO2 <=> Ts} relationship, and global imprints of the same relationship in Vostok ice cores. Assuming that the theory of CO2 as major driving force of climate is correct, we should be able to compare sensitivities of climate to CO2 between the two experimental datasets, and models.

If you disagree with this parallel, please submit your objections, preferably in a more argumentative form than a bold reference to an ill-thought essay.
post #63 of 119
Frankly I'm not the least bit interested in arguing with you.  I have more than my share of arguments with deniers on YA every day.

Obviously nothing anyone can say is going to convince you that you're wrong.  I mean you dismissed my entire wiki as "oh it's just CO2 and those other feedbacks I already dismissed".  Just for starters methane isn't CO2.  On top of that CO2 acting as a feedback isn't the same as CO2 acting as a forcing.

But like I said, I'm not going to argue with you.  If you're going to just dismiss my entire wiki like that, it's obviously a complete waste of time.  Maybe Dawei will have more patience than me, but I'm just not interested.  Arguing with deniers is like arguing with a brick wall.
post #64 of 119

I'm not really sure why you're so hell bent on this. I acknowledged that I thought it could be a quick way of getting a rough estimate of future temperature change, I'm just pointing out that there are more complications. Declining absorbance by the oceans, a changing biosphere, permafrost instability, emissions of other greenhouse gasses, aerosol concentrations, band saturation, equilibrium time, changes in oceanic cycles, stratospheric ozone sinking,  ice and terrestrial albedo, natural variations, changes in clouds, etc. etc.  

 

But in any case, why don't you just go ahead and say what you’ve been waiting to say? Let’s say that everything on the entire planet will remain constant for the next 100 years and only CO2 levels will control the magnitude of the temperature rise. You asked if I thought extrapolating the historical correlation was a valid technique: let’s just pretend I said yes. So go on and make your point.

post #65 of 119
Dana said:
Obviously nothing anyone can say is going to convince you that you're wrong.  I mean you dismissed my entire wiki
Obviously this is a wrong presumption. A good coherent argument could well convince me. But what else could you expect other than dismissal of your ENTIRE WIKI? Your article begins with glaringly erroneous formulation:
Quote:

Climate sensitivity is a term which describes how sensitive the global climate is to an increase in temperature
Don't you see that this mere introduction is already wrong? "Global climate" is a near synonym of "global temperature", and sensitivity of climate was always defined as sensitivity to some other external parameter, axial tilt, raw insolation, GH concentration, continent shift, etc. In a completely narrow definition, it is a sensitivity to CO2 doubling,

Quote from IPCC AR4:

The equilibrium climate sensitivity is a measure of the climate system response to sustained radiative forcing. It is not a projection but is defined as the global average surface warming following a doubling of carbon dioxide concentrations.
Are you always that sloppy, from the very beginning?

Quote:

Just for starters methane isn't CO2.
What's the difference? Permafrost is partially melting every season on vast terrain of Siberia, Canada, and Alaska, so the methane that comes out does contribute all it can, proportionally to the surface warming trend, be it today, or 20000 years ago. Same goes for alleged deposits of "frozen carbon". So, this argument is dismissed too.

Quote:

On top of that CO2 acting as a feedback isn't the same as CO2 acting as a forcing.
How so? CO2 is CO2, and IR photons do not differentiate which CO2 molecule makes forcing, and which one came later from feedback. Nonsense dismissed.

Quote:

But like I said, I'm not going to argue with you.  If you're going to just dismiss my entire wiki like that, it's obviously a complete waste of time.
Entirely agree. You are not going to argue with me because you cannot coherently refute any of my arguments.

So, shall we proceed with comparing climate sensitivities derived from instrumental records, and records from ice cores?
post #66 of 119
See, I'm torn.  Because your arguments are wrong and easily refutable.  But if I do so, it will be a complete waste of time, because you're not a rational person.  You'll just come up with some bogus argument why I'm wrong (for example, virtually every argument you just made).  So why waste my time?

I've argued with a number of "skeptics" just like yourself, and none has proven capable of changing his entrenched mindset.  You provide them with concrete evidence that they're wrong, and they find some way to dismiss it, just like you do.  I mean geez, you insult my wiki because I said climate sensitivity is a measure of the response to an increase in temperature rather than an increase in radiative forcing.  Give me a freaking break.  I'm trying to write these things at an introductory level so anyone can understand them, and you use that as an excuse to dismiss the entire argument.

As I said, I'm not interested in wasting my time.  If you really want to argue, bug Dawei.  But just to give you a little hint where you're obviously wrong, a relatively small amount of CO2 and methane emissions don't have the same impact on global temperature as a large amount of CO2 and methane emissions.  It amazes me you just gloss over this with the "oh it's just more CO2 so it doesn't matter" argument.
post #67 of 119
Dana wrote:
See, I'm torn.  Because your arguments are wrong and easily refutable.  But if I do so, it will be a complete waste of time, because you're not a rational person.
Oh no, I am a very rational person. You just wasting more time saying that it is waste of time. You just need to produce a rational argument, especially if it is so easy, which you failed to do so far.

Quote:

I've argued with a number of "skeptics" just like yourself, and none has proven capable of changing his entrenched mindset.  You provide them with concrete evidence that they're wrong, and they find some way to dismiss it, just like you do.
Why do you think that it were skeptics who were incapable? Maybe it is because your evidence is not as concrete as you were led to believe?

Quote:

Give me a freaking break.  I'm trying to write these things at an introductory level so anyone can understand them, and you use that as an excuse to dismiss the entire argument.
If you think that glossy errors in introductory texts helps to understand them, you are sadly mistaken. I tried to find any "entire argument" in your article, and immediately run into this error. However, I found one useful statement from your wiki: "Climate sensitivity is the amount the planet will warm when accounting for all of these feedbacks." Would you stand behind this definition?

Quote:
But just to give you a little hint where you're obviously wrong, a relatively small amount of CO2 and methane emissions don't have the same impact on global temperature as a large amount of CO2 and methane emissions.  It amazes me you just gloss over this with the "oh it's just more CO2 so it doesn't matter" argument.
Ok, I could miss something here. Your little hint game does not ring any bell. Care to waste a paragraph or two on it? See, I am very reasonable ...
post #68 of 119
All the information is right there in the wiki.  If you want to dismiss it offhand, that's your choice, and I'm not going to waste any more time trying to explain it to you.

Bottom line is that climate sensitivity is pretty close to 3°C warming for a doubling of CO2 (in the short-term, maybe as high as 6°C in the long-term).  The danger limit is set at 2°C.  We're on track to reach the doubled CO2 level by around mid-century.  Once we pass 2°C, there's a high risk that various feedbacks will kick in and accelerate the warming beyond our control.

It's not difficult to put 2 and 2 together here.
post #69 of 119
Quote:
All the information is right there in the wiki.  If you want to dismiss it offhand, that's your choice, and I'm not going to waste any more time trying to explain it to you.
Indeed it is very difficult to explain unexplainable, and waste of time is very likely. Here is a statement from your wiki: "Climate sensitivity is the amount the planet will warm when accounting for all of these feedbacks." And you said that consensus for climate sensitivity is 3 deg.C/2xCO2.

You also trust paleoclimatological proxies, tree rings, etc, and therefore you should believe in ice core data, correct? Then take a close look at Vostok ice cores. One can extract pairs of data, T and CO2, and build a correlation chart, like this one:

http://www.ferdinand-engelbeen.be/klimaat/correlation.html

It has CO2 range about 180 to 300 ppm, or nearly full doubling, with corresponding T range 279-292K. Apparently, these observational data are the result of all possible feedbacks, and therefore must correspond to current models of climate sensitivity, which, as you defined it, include all feedbacks.
 
Making a standard AGW assumption that greenhouse gases are the major driver for surface temperatures, the data must fit into logarithmic formula, T = a*LN(CO2)+b. If you do this, it appears that the climate sensitivity would be 14.74 C per CO2 doubling.
If you limit your data set to intensive deglaciation episodes, where the standard climate change theory definiely expects CO2 as the major driving force, the "sensitivity" jumps to 18 C/2xCO2, with correlation coefficient up to 0.92.

What would be your explanation for such a glaring discrepancy between modern understanding of global climate sensitivity and observational data?
post #70 of 119
Quote:
Originally Posted by AlTekhasski View Post

What would be your explanation for such a glaring discrepancy between modern understanding of global climate sensitivity and observational data?

 

Aside from the fact that you're ignoring all non-CO2 forcings, you're also assuming that climate sensitivity constant at all temperatures.  It's not.  Different feedbacks are triggered at different temperatures.  The 3°C sensitivity is for a change in atmospheric CO2 from 280 to 360 ppm.
post #71 of 119
Quote from Dana:
Aside from the fact that you're ignoring all non-CO2 forcings,
Which all other forcings? Milankowitch forcing is zero, which one else? Cosmic Ray forcing? we might have some starting point here, but you are denying it completely. As you said, all other stuff are feedbacks, methane, water vapor, ice albedo, forests, all, according to yourself, are feedbacks, according to your own wiki.

Quote from Dana:

you're also assuming that climate sensitivity constant at all temperatures.  It's not.  Different feedbacks are triggered at different temperatures.
The range of global temperatures in Vostok cores is 279K-292K. Today's accepted value is 288K, which is perfectly within that range. Therefore, all feedback influences must be the same as today. Argument dismissed.

Quote from Dana:

The 3°C sensitivity is for a change in atmospheric CO2 from 280 to 360 ppm.
The CO2 range in Vostok cores is 180 - 300ppm, which included your starting point of 280ppm. So, your argument is dismissed again. More, you apparently did not grasp the whole point of concept of "doubling", when, due to logarithmic physical nature of GH forcing, it does not matter where do you start, at 200ppm, or at 400ppm, or at 800ppm - every doubling leads to the same increase of temperature.

So, what do we have? We have that you are not capable of explaining anything. And this is likely not because that you are not smart enough, but likely because the basic premise of AGW (CO2 as major driver of climate) is dumb at its root.

So, my point stands as follows:  we have modern instrumental records that yield the "global climate sensitivity" of 2.26K/2xCO2, and the ice core records that yield 18K/2xCO2, The discrepancy is 8-fold, or an order of magmitude. Given that all natural conditions are within the same initial range and therefore same feedbacks must be in place, the hypothesis that CO2 is driving climate is clearly incapable to explain this discrepancy. This leads to inescapable conclusion that CO2 is a secondary factor in climate dynamics, since even 12-fold artificial (presumably man-made) increase in CO2 growth rate did not result in any warming influence on global temperatures.

(and yes, I am familiar with Lorius-Hansen's "analysis" (1990) of ice-core records.)

Please correct me if I am wrong here. So far all your patronizing was lacking any specifics.
post #72 of 119
Quote:
Originally Posted by AlTekhasski View Post

Quote from Dana:
Which all other forcings? Milankowitch forcing is zero, which one else?


The orbital forcing is not zero.  Right now it's slightly negative, close to zero.  There's also the solar forcing, which right now is roughly zero.  But this was in reference to your discussion of paleoclimate, not current climate.  In talking about paleoclimate you completely ignored all non-CO2 forcings.

Quote:
The CO2 range in Vostok cores is 180 - 300ppm, which included your starting point of 280ppm. So, your argument is dismissed again.

Obviously that was a typo, since a doubling from 280 brings us to 560 ppm (not 360 - in fact we're already well above 360 ppm).  Notwithstanding the fact that even 360 is above 300.  Dismissal dismissed.

Quote:
So, my point stands as follows:  we have modern instrumental records that yield the "global climate sensitivity" of 2.26K/2xCO2, and the ice core records that yield 18K/2xCO2, The discrepancy is 8-fold, or an order of magmitude. Given that all natural conditions are within the same initial range and therefore same feedbacks must be in place, the hypothesis that CO2 is driving climate is clearly incapable to explain this discrepancy.
 

The discrepancy is due to the first point above, that you're ignoring all non-CO2 paleoclimate forcings.  You're comparing apples to oranges.  Basically what you're saying is that 'in period X when CO2 doubled and all these other things happened (orbital and solar forcings, for example), the global temperature changed more than now when CO2 is poised to double and those other forcings are approximately zero.'

You're treating sensitivity solely as a response to increasing CO2.  It's not.  As you have already noted, sensitivity is a response to *all* forcings.

Quote:
This leads to inescapable conclusion that CO2 is a secondary factor in climate dynamics

It has previously been a feedback, and rarely a forcing, if that's what you mean.

Quote:
since even 12-fold artificial (presumably man-made) increase in CO2 growth rate did not result in any warming influence on global temperatures.
 

You mean other than the ~1°C warming over the past century?  Yeah other than that rapid warming, the CO2 growth rate didn't cause any warming!
Edited by dana1981 - 12/18/09 at 9:10am
post #73 of 119
Quote:
Originally Posted by dana1981 View Post

You mean other than the ~1°C warming over the past century?  Yeah other than that rapid warming, the CO2 growth rate didn't cause any warming!

Not to mention that we haven't seen all the warming from the rise of CO2 from 280 to 380 ppm that there will be since the system hasn't come to equilibrium yet.  It's only been 150 years since CO2 started to increase but the deglaciation from an ice age took 5000 years.  There's a lot of thermal inertia in the system. 

You can infer broad generalizations about the physical mechanisms involved in climate from studying the onset and temination of ice ages, but thinking that what happened then is directly analogous to the modern era is absurd.  Unless you're a skeptic. 
post #74 of 119
Quote:
Originally Posted by gcnp58 View Post


You can infer broad generalizations about the physical mechanisms involved in climate from studying the onset and temination of ice ages, but thinking that what happened then is directly analogous to the modern era is absurd.  Unless you're a skeptic. 

 


Exactly my point.  But to give AlTek a little credit, he doesn't oversimplify as much as most of his fellow 'skeptics', whose new favorite argument seems to be "the planet is warming because it was colder a few centuries ago during the LIA."  It boggles my mind that anyone over the age of 5 could possibly think this is an intelligent argument.

At least AlTek's arguments aren't as simplistic, although that means I have to expend a bit more effort in explaining where they're flawed.

post #75 of 119
Quote from Dana:
although that means I have to expend a bit more effort in explaining where they're flawed.
So far your bits of efforts yield no relults, and the explanations are no more than mumbling. You both are murmuring about "all non-CO2 forcings" without any substantiation, several times already. It is well known that the globally-averaged Milankovitch "forcing" is nearly zero, a fraction of a watt per m2, and "solar forcing" is a climatological constant as well for the last 100M years at least. Again, you contradict yourself regarding "non-CO2 forcing, since you (and me a well) believe that
Quote from your wiki:
"Climate sensitivity is the amount the planet will warm when accounting for all of these feedbacks."
So, all that methane, ice cups, water vapor, are all feedbacks arising from the elevated surface temperatures regardles of what causes them, and are included in experimental data sets proportionally to covered temperature ranges.

I repeat my point: the experimental conditions do overlap for the two data sets, and therefore climate in all these warming episodes (current and past) must be influenced by the same set of forcings and feedbacks, and in the same proportion. This proportion gets captured from evaluation of the slope of corresponding CO2-T correlation charts. It is not a mere "onset and termination", it is a differential metrics across the entire data set. Yet the derived sensitivities differs by 8x, or nearly by an order of magnitude. Therefore, it seems obvious that the standard CO2-driven theory of climate has failed the experimental test and therefore is absurd. Obviously, the alternative explanation that CO2 does not drive nor define the Earth climate seems to have much more sense.
In the light of the above argument, your remark, quote:
 You mean other than the ~1°C warming over the past century?  Yeah other than that rapid warming, the CO2 growth rate didn't cause any warming!
looks one-sided and rather silly.

The thermal inertia argument may have some merit; however this would imply that we should expect the reaction to CO2 to be no less than its natural state, which appears to be 18 K/2xCO2. Are you trying to say that all scientists working on GCMs are wrong and vastly underestimate the climate reaction to CO2 and resulting feedbacks? That would be a strong claim against computational climatology.
post #76 of 119
Quote:
Originally Posted by AlTekhasski View Post

Therefore, it seems obvious that the standard CO2-driven theory of climate has failed the experimental test and therefore is absurd. Obviously, the alternative explanation that CO2 does not drive nor define the Earth climate seems to have much more sense.
 

Nobody is claiming CO2 drove climate changes in the past.  It acted as a feedback.  Thus your conclusion that CO2 didn't drive climate change in the past is a "no duh" moment.

All you're doing is taking the logical fallacy "climate change happened naturally in the past, therefore humans can't cause climate change" and trying to dress it up.  However, your logical flaws are still quite transparent.
post #77 of 119
Quote:
Nobody is claiming CO2 drove climate changes in the past.  It acted as a feedback.  Thus your conclusion that CO2 didn't drive climate change in the past is a "no duh" moment.
Not so fast. From your own "wiki", quote:
This is often referred to as the '800 year lag'.  Sometimes this lag is mistakenly cited as evidence that carbon dioxide cannot cause global warming.  However, after the 800 year lag, CO2 amplified global warming for several thousand years.  While carbon dioxide did not initiate these previous warmings, it did amplify and cause further warming. 
So, you are asserting that CO2 "did amplify and cause further warming". One cannot cause or amplify something without "forcing" (or "driving") it. So, in fact you do claim that CO2 drove temperatures to higher levels.

More, in climatology, climate is assumed to relax to an equilibrium. Regardless of CO2 being feedback, forcing, or other gobbledygook of effects, the climate system develops certain relationship between CO2 and T (or between T and CO2). According to the Vostok data for deglaciation episodes, this relationship produces climate sensitivity of 18 K/CO2_doubling, or, equivalently, 11 ppm/K of CO2 outgassing.
Vostok ice data, for rapid deglaciation episodes only
CO2 <-> T correlation for Vostok ice data, for rapid deglaciation episodes only

Therefore, for a given modern 35% increase in CO2, the global temperature must be rapidly approaching +8 degree increase, all just from the natural (alleged) CO2->T relationship. It does not, nowhere close to this, especially if you consider other anthropogenic factors as black soot over Earth ice sheets. The signal of such amplitude must be easily identifiable. Instead, the temperature rise is barely distinguishable from weather noise. Therefore, the theory that "CO2 amplifies and causes further warming" is also invalidated by observational evidence.

You continue along to escalate a thesis that I have not made, quote:

All you're doing is taking the logical fallacy "climate change happened naturally in the past, therefore humans can't cause climate change" and trying to dress it up.  However, your logical flaws are still quite transparent.
If you bother to check, I have not made any reference in my previous posts about any ability or inability of human to cause any climate change. I was arguing (purely academically) that the idea of dominant role of CO2 in climate dynamics does not pass the experimental test. Now, please summarize where are my logical flaws here.
post #78 of 119
Do you understand what a feedback is?  It's not the same thing as a forcing.  Repeatedly claiming they're the same thing doesn't make it so.
post #79 of 119
Dana wrote, quote:
Do you understand what a feedback is?  It's not the same thing as a forcing.  Repeatedly claiming they're the same thing doesn't make it so.
I do, but it looks like you do not. In a closed system, all variables are coupled and affect each other, especially if you are talking about THE SAME SYSTEM VARIABLE as CO2. It is a CLOSED LOOP, CO2-> T -> CO2 ->T -> CO2... etc, the feedback becomes a forcing as time progresses. As I already tried to explain to you, radiation cannot differentiate between CO2 absorbing-emitting molecules, and the forcing-feedback distinction has no meaning.

The only excuse in this logic is the progress of time, all relative to characteristic relaxation times of system components. It is true that oceans have substantial thermal inertia. However, given the average ocean's column of water of 3800m and even assuming instant mixing, the alleged radiative imbalance of 3.7W/m2 should lead to ocean warming by 1K/100y, a trend that should be quite measurable. Instead, all efforts to detect changes in ocean heat content show that the responsible  flux imbalance cannot exceed 0.15W/m2 . This points out in the same direction: increases in CO2, even if being a known greenhouse gas, do not create radiative imbalances at the levels assumed in current climatology, and therefore we come back to the same conclusion: at current levels, changes in CO2 do not define Earth climate.
post #80 of 119
Originally Posted by AlTekhasski View Post
Regardless of CO2 being feedback, forcing, or other gobbledygook of effects, the climate system develops certain relationship between CO2 and T (or between T and CO2). According to the Vostok data for deglaciation episodes, this relationship produces climate sensitivity of 18 K/CO2_doubling, or, equivalently, 11 ppm/K of CO2 outgassing.

But you can't quantify with any certainty how much of the rise in temperature was due to the rise in CO2, because we don't know with any great certainty what caused those warming events. It's suggested that orbital forcings were the main trigger but even that is in question. The system is significantly more complex than T = f(CO2). You're trying to make the assumption that the rise was 100% because of the CO2 forcing and that's just not even close to reality.

All you have shown is evidence that an 18 K rise would lead to a doubling of CO2. This fact is completely independent of the cause of the temperature rise and says nothing about the magnitude of warming that a doubling of CO2 would effect. The two do indeed always rise together but for completely different reasons. One is based on the temperature dependence of Henry's Law, another on the complex world of IR spectroscopy. Why would you expect those two to have anything to do with each other?
post #81 of 119
Quote:
Originally Posted by dawei View Post



But you can't quantify with any certainty how much of the rise in temperature was due to the rise in CO2...The system is significantly more complex than T = f(CO2). You're trying to make the assumption that the rise was 100% because of the CO2 forcing and that's just not even close to reality.

All you have shown is evidence that an 18 K rise would lead to a doubling of CO2. This fact is completely independent of the cause of the temperature rise and says nothing about the magnitude of warming that a doubling of CO2 would effect. The two do indeed always rise together but for completely different reasons.

 

Precisely.

To put it as simply as possible, consider the scenario where factors A, B, and C can cause a global temperature change.

In scenario 1, A increases by a factor of 10, B by a factor of 3, and C by a factor of 2.  The global temperature increases by 18K in response.

In scenario 2, A and B remain constant while C increases by a factor of 1.4.  The global temperature rises 1.5K in response.

From these 2 scenarios you conclude that changes in C don't drive climate change, or whatever it is that you're arguing.  Obviously this argument is illogical and does not follow from the scenarios in question.
post #82 of 119
Dawei wrote, quote:
But you can't quantify with any certainty how much of the rise in temperature was due to the rise in CO2, because we don't know with any great certainty what caused those warming events. It's suggested that orbital forcings were the main trigger but even that is in question. The system is significantly more complex than T = f(CO2). You're trying to make the assumption that the rise was 100% because of the CO2 forcing and that's just not even close to reality.
This is not my assumption, this is an assumption of standard climatology, that T is determined by radiative forcing from CO2 and all resulting feedbacks. Since the global Milankovitch forcing remains 0, especially on 100,000 cycles, and CO2 in air is what it is, and "self-feedback of CO2" cannot act any other way than as forcing itself, that's why nearly 100% comes to play. Regarding "all other feedbacks and forcings", that's exactly the point in question.

The Vostok data show that the T <=> CO2 relationship did not change over at least four last events, each nearly 120,000 years apart, since all events fell into the same line, at least with a customary climatological accuracy. More, the entire relationship has a relatively small scatter of data, which indicates that no other parameters were different in any substantial degree (again within typical climatological accuracy). Therefore, speaking in terms of Dana's example, the change in hypothetical factors A and B (if any) were the same across all four ice ages. The point I am trying to make is that there is no reason to belive that the factors A and B are any different today than 18,000 or 140,000 years ago: ice cups are still there and shrinks and expands in accord with same climate dynamics, and oceans are still there, and seasonally-thawing zones produce same methane.  I asked you to name these factors, but you both responded only hypothetically, which is not satisfactory. If there are any new factors today (as soot and agriculture changes), they work in the direction to intensify warming, and not to decrease it as Dana's scenario 2 would require.

Quote:
All you have shown is evidence that an 18 K rise would lead to a doubling of CO2. This fact is completely independent of the cause of the temperature rise and says nothing about the magnitude of warming that a doubling of CO2 would effect. The two do indeed always rise together but for completely different reasons. One is based on the temperature dependence of Henry's Law, another on the complex world of IR spectroscopy. Why would you expect those two to have anything to do with each other?
This is exactly right: historical changes in CO2 say nothing about the magnitude of warming from CO2 doubling, there might be little to no warming at all. However, this would contradict to entire AGW hypotesis. The link between two dependencies, CO2 = h(T) and T = f(A, B, CO2, D,... ) hangs entirely on presence or absence of differences in factors A, B, etc. between the historical warming events and the alleged anthropogenic event. So far you failed to name these differences.

Therefore, in order to explain substantial discrepancy in climate sensitivities derived from different observational evidences, we have several variants:
(A) There is a substantial unidentified forcing that causes historical swings into and from ice ages;
(B) Climate sensitivity to radiative forcing from CO2 doubling is about 1/10th of current projections;
(C) There is no (A) but climate sensitivity is 5x of current estimates;
(D) Climate fluctuates for no apparent reason in accord with internal chaotic dynamics of interplay between ocean currents, salinity, and ice sheets configuration while (B);
(E) Any combination of (A) and (increased_B);
(F) Any combination of (D) and (increased_B);

In all cases the magnitude of natural climate dynamics remains undetermined, and therefore all musings about "unprecedented" climate change are unsubstantiated. Looks like a lot of work to do for climatology, and so little place for certainty for policy advices.
post #83 of 119
Quote  from Dana:
In scenario 1, A increases by a factor of 10, B by a factor of 3, and C by a factor of 2.  The global temperature increases by 18K in response.

In scenario 2, A and B remain constant while C increases by a factor of 1.4.  The global temperature rises 1.5K in response.

From these 2 scenarios you conclude that changes in C don't drive climate change, or whatever it is that you're arguing.  Obviously this argument is illogical and does not follow from the scenarios in question.
The purpose of my exercise was to show that ice data and modern data cannot be reconciled within current official climatology, where CO2 is declared as main (and "well understood") forcing. As your example shows, you need another big unknown factor "A" to explain ice ages, the factor you cannot name. If you cannot name this factor and cannot explain its behavior in time and its causes, it is obviously illogical to claim that today the factor "A" is not present, today's climate change is "unprecedented" and is solely attributable to CO2, and the "science is settled".
post #84 of 119

This is not my assumption, this is an assumption of standard climatology, that T is determined by radiative forcing from CO2 and all resulting feedbacks.

 

No it isn’t, why do you keep insisting on this. T is determined by radiative forcing, no matter what causes it. There is nothing inherently special about the forcing caused by CO2. And why do you keep saying “Milankovitch forcing remains 0, especially on 100,000 cycles”? This is precisely the cycle in which it has the MOST forcing. To say it’s zero on a 100K year timescale is basically saying it never has any effect at all.

 

“The Vostok data show that the T <=> CO2 relationship did not change over at least four last events

 

All that the Vostok correlation indicates is that there were no other significant sources of CO2 emission other than oceanic release.

 

This is exactly right: historical changes in CO2 say nothing about the magnitude of warming from CO2 doubling, there might be little to no warming at all. However, this would contradict to entire AGW hypotesis.

 

No it wouldn’t. Do you really think AGW demands 18 K / CO2 doubling? Don’t you think somebody would have figured that out already?

 

And there is no link between CO2 = h(T) and T = f(A, B, CO2, D,... ). Temperature should rise from increases in CO2 but it’s just a coincidence of nature that the inverse is also true. If Earth were just a rock and there were no oceans to warm and expel their dissolved CO2, the historic correlation would not exist at all. By your logic that would mean that CO2 can never cause any rise in temperature, and that’s a ridiculous conclusion to make. The quantity of CO2 historically released by oceanic warming is completely independent of its strength as a radiative forcing agent.

post #85 of 119
Quote:
Originally Posted by AlTekhasski View Post

Quote  from Dana:
you need another big unknown factor "A" to explain ice ages, the factor you cannot name. If you cannot name this factor and cannot explain its behavior in time and its causes, it is obviously illogical to claim that today the factor "A" is not present, today's climate change is "unprecedented" and is solely attributable to CO2, and the "science is settled".

WTF are you talking about?  It's called the Milankovitch cycles and associated orbital forcing.

I'm tired of arguing with the brick wall.  Dawei, he's all yours.
post #86 of 119
Dana wrote, quote:
WTF are you talking about?  It's called the Milankovitch cycles and associated orbital forcing.
And Dawei writes, quote:

And why do you keep saying “Milankovitch forcing remains 0, especially on 100,000 cycles”? This is precisely the cycle in which it has the MOST forcing. To say it’s zero on a 100K year timescale is basically saying it never has any effect at all.


Apparently you have a very narrow knowledge of what the “F” these orbital forces are. Let me provide an excurse into some unpopular details of the subject.

 

First, global climate change is a global concept, so the first order effect comes form global change in solar energy. Calculations based on astronomically-accurate orbital data show that the globally averaged annual insolation from orbital changes does not vary for more than +-0.5%. You can check this from this insolation calculator:

http://geoflop.uchicago.edu/forecast/docs/Projects/orbit.html

Pick a year, and average the yearly data in Excel.

Some numbers, to save you a trouble:

147,000 years ago -  298.83 W/m2 - near glacial minimum;

128,000 years ago -  301.58 W/m2 - after deglaciation;

4 years ago -  300.06 W/m2

 

So, the direct “forcing” form orbital changes is nearly zero, as I stated.

 

Now, to squeeze out any effect out of orbital changes, climatology invented a clever scheme for a secondry effect that requires a certain position of lands relative to arctic waters in high latitudes, where a complex sublimation/evaporation process of ice accumulation may take place:

http://www.ithelps.ch/grosjean/Quaternary%20Climates%20S7461/Chapter%203%20(Monsoon)/Additional%20reading/Ruddiman%202006.pdf

To appreciate complexity of this enhanced theory, take a look this presentation:

http://ncclcs.cma.gov.cn/FCKeditor/userimages/ncclcs-20070724031327.pdf

 

The entire theory is based on eye-ball coincidence between some obscure peaks in data with astronomically-accurate time wiggles of insolation at certain carefully selected location, 65N. However, if a rigorous analysis of data is performed, a somewhat different picture emerges:

http://ocean.mit.edu/~cwunsch/papersonline/milankovitchqsr2004.pdf

 

“A number of records commonly described as showing control of climate change by Milankovitch insolation forcing are reexamined. The fraction of the record variance attributable to orbital changes never exceeds 20%. In no case, including a tuned core, do these forcing bands explain the overall behavior of the records. At zero order, all records are consistent with stochastic models of varying complexity with a small superimposed Milankovitch response, mainly in the obliquity band. Evidence cited to support the hypothesis that the 100 Ka glacial/interglacial cycles are controlled by the quasi-periodic insolation forcing is likely indistinguishable from chance…”

 

 Additional analysis shows that all paleodata are just a classic 1/f noise:

http://www.pnas.org/content/99/suppl.1/2546.full.pdf+html

 

Some historical overview of discrepancies with observational data can be found here:

http://www.detectingdesign.com/milankovitch.html

 

That was the “F” I was talking about. As you can see, the Milankovitch theory has more problems than explanations it offers.

post #87 of 119
Quote:
Originally Posted by AlTekhasski View Post

Dana wrote, quote:
And Dawei writes, quote:

Apparently you have a very narrow knowledge of what the “F” these orbital forces are. Let me provide an excurse into some unpopular details of the subject.

 

 

 

First, global climate change is a global concept, so the first order effect comes form global change in solar energy. Calculations based on astronomically-accurate orbital data show that the globally averaged annual insolation from orbital changes does not vary for more than +-0.5%. You can check this from this insolation calculator:

 

http://geoflop.uchicago.edu/forecast/docs/Projects/orbit.html

 

Pick a year, and average the yearly data in Excel.

 

Some numbers, to save you a trouble:

 

147,000 years ago -  298.83 W/m2 - near glacial minimum;

 

128,000 years ago -  301.58 W/m2 - after deglaciation;

 

4 years ago -  300.06 W/m2

 

 

 

So, the direct “forcing” form orbital changes is nearly zero, as I stated.

 

 

 

Now, to squeeze out any effect out of orbital changes, climatology invented a clever scheme for a secondry effect that requires a certain position of lands relative to arctic waters in high latitudes, where a complex sublimation/evaporation process of ice accumulation may take place:

 

http://www.ithelps.ch/grosjean/Quaternary%20Climates%20S7461/Chapter%203%20(Monsoon)/Additional%20reading/Ruddiman%202006.pdf

 

To appreciate complexity of this enhanced theory, take a look this presentation:

 

http://ncclcs.cma.gov.cn/FCKeditor/userimages/ncclcs-20070724031327.pdf

 

 

 

The entire theory is based on eye-ball coincidence between some obscure peaks in data with astronomically-accurate time wiggles of insolation at certain carefully selected location, 65N. However, if a rigorous analysis of data is performed, a somewhat different picture emerges:

 

http://ocean.mit.edu/~cwunsch/papersonline/milankovitchqsr2004.pdf

 

 

 

“A number of records commonly described as showing control of climate change by Milankovitch insolation forcing are reexamined. The fraction of the record variance attributable to orbital changes never exceeds 20%. In no case, including a tuned core, do these forcing bands explain the overall behavior of the records. At zero order, all records are consistent with stochastic models of varying complexity with a small superimposed Milankovitch response, mainly in the obliquity band. Evidence cited to support the hypothesis that the 100 Ka glacial/interglacial cycles are controlled by the quasi-periodic insolation forcing is likely indistinguishable from chance…”

 

 

 

 Additional analysis shows that all paleodata are just a classic 1/f noise:

 

http://www.pnas.org/content/99/suppl.1/2546.full.pdf+html

 

 

 

Some historical overview of discrepancies with observational data can be found here:

 

http://www.detectingdesign.com/milankovitch.html

 

 

 

That was the “F” I was talking about. As you can see, the Milankovitch theory has more problems than explanations it offers.


That PNAS paper clearly states that the 1/f noise is true only for frequencies shorter than 1/40kYr (in other words, once you get away from the timescale of the Milankovitch forcing, it's white noise, but that on frequencies of the Milankovitch forcing it isn't and it is highly correlated). 

Now, if what you are claiming is true and the system is simply highly stochastic and sensitive so that it switches around on its own, why do you think a longwave radiative forcing from the anthropogenic greenhouse gases of around 2.5 W/m^2 would have no effect on this very sensitive system?  What makes you believe that a highly nonlinear system that is not deterministic cannot be forced by some outside driver?  Even a nonlinear overdriven amplifier will have a somewhat deterministic response to an applied input. 

I get what you're saying, and I can see where if I were predisposed to emotionally reject the idea that humans are modifying climate I would be taken in by the nonsense you've posted, but objectively I don't see how you connect the dots from "all climate is stochastic and ice ages are unrelated to Milankovitch forcing" to "anthropogenic CO2 can have no effect on climate."   See, the problem is that no matter whether Milakonvitch forcings trigger the beginning and end of ice ages, you can't get ice ages to start or stop without including the radiative effects from CO2 (along with the radiative effects of changes in albedo).  So the theory of Wunsch doesn't really address what is going to happen from anthropogenic CO2, although we know from the paleo record that climate does respond to changes in atmospheric CO2. 
post #88 of 119
Since this topic was originally about Monbiot, I thought it would be worth mentioning that he recently debated Ian Pilmer (denier geologist) and soundly trounced him.  You can see the transcript and video here.  Most of the "debate" involved Monbiot and the moderator confronting Pilmer about one of the many lies he's spouted, Pilmer dodging the question, Monbiot/moderator repeating the question, and Pilmer continuing to dodge it with a series of ad hominem attacks and nonsensical rambling.

The saddest part is that Pilmer even lost the debate on a geology question (CO2 emitted by volcanoes vs. humans).  To a journalist!  That's pretty pathetic.
post #89 of 119
That was a depressing transcript (no video here) to read.  The only thing I got from the debate was that Monbiot is a journalist with some science knowledge and Pilmer is a sorry excuse for a scientist.  I guess many already knew that, though.  What a waste of a debate.
post #90 of 119
Dawei wrote, quote:

And there is no link between CO2 = h(T) and T = f(A, B, CO2, D,... ).

We have a coupled system,

change = dissipation{A,B,CO2, D, T} + forcing,

which allegedly has a stationary point. This point moves in state space if forcing changes. There is always a relationship between C = h(T) and T =f(…C…). The variables are linked via the system condition of stationary balance. CO2 and T are not independent.

 

Dawei continues, quote:

Temperature should rise from increases in CO2 but it’s just a coincidence of nature that the inverse is also true.

The first part is not universally true.

 

Dawei continues, quote:

If Earth were just a rock and there were no oceans to warm and expel their dissolved CO2, the historic correlation would not exist at all. By your logic that would mean that CO2 can never cause any rise in temperature, and that’s a ridiculous conclusion to make.

Good example. But there have been significant historical variations in temperature, and in your rock example the corresponding CO2 variations would be very-very small. However, the historical changes are customary attributed to rising GH gases, and in case of Vostok cores people like you say that “CO2 rose together and must drive temperatures up”. Then by your  “rock-solid” logic that would mean that climate is “very sensitive to small changes in GH gases” because you do not have any other explanation for temperature changes other than greenhouse gases. This would be also a very ridiculous conclusion to make, would you agree? I am curious who would make such a conclusion among climatologists? 

 

The quantity of CO2 historically released by oceanic warming is completely independent of its strength as a radiative forcing agent.

See above.

So, my point still stand: you need some unidentified force to drive ice ages. We see that orbital forces are weak, secondary effects from localized orbital variations are highly speculative, and greenhouse driver theory cannot fit loose ends. It looks like the entire foundation of AGW theory is nonsense, sorry.

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