Deal with Climate Reality as it Unfolds....

[Michael Hardner]

Even there you are conceding far too much. #3 is a fact in that warming in itself would be climate change. #1 and #2, however, are theories that have yet to be proven.

#1 and #2 are as proven as they ever will be. Even if our winters go to 30C and Carbon counts increase, there will be no way to 'prove' they are linked beyond what we have already done. This is like saying that's it's not 'proven' that smoking causes cancer. You can't create a double-blind experimental person to test the theory on, any more than you can create a double-blind earth to test on.

[wyly]

#1 and #2 are as proven as they ever will be. Even if our winters go to 30C and Carbon counts increase, there will be no way to 'prove' they are linked beyond what we have already done. This is like saying that's it's not 'proven' that smoking causes cancer. You can't create a double-blind experimental person to test the theory on, any more than you can create a double-blind earth to test on.

#2 has been established fact since 1859...Bryan must getting his info from the Wildrose Party ...

[waldo]

1) Humans emissions of CO2 are causing the level of CO2 to rise;

2) CO2 is a GHG which will cause the planet to warm;

3) A warming planet means the climate will change;

Even there you are conceding far too much. #3 is a fact in that warming in itself would be climate change. #1 and #2, however, are theories that have yet to be proven.

#2 has been established fact since 1859...Bryan must getting his info from the Wildrose Party ...

imagine! There are still some that "declare" the fundamental physical science basis of the Greenhouse Effect... a theory. There are still some that deny the enhanced affect of anthropogenic sourced CO2 on that Greenhouse Effect.

as for the misguided nature of MLW member 'Bryan's' #1 "theory" declaration:

...the 3 relevant isotopes (C12, C13, C14), these carbon isotope variants offer undeniable proof that the increasing atmospheric CO2 levels are anthropogenic in nature; specifically:

- fossil fuels, forests, and soil carbon derive from the strongly depleted C13 photosynthetic carbon... plants have a lower C13/C12 ratio than that found in the atmosphere. The recent (since 1850 on) increase in atmospheric CO2 levels has resulted in an observed parallel decline in the C13/C12 ratio of atmospheric CO2

- fossil fuels do not contain C14. The recent (since 1850 on) increase in atmospheric CO2 levels has resulted in an observed parallel decline in the C14/C12 ratio of atmospheric CO2

on edit: to add...

...CO2 emissions rising increases the level of C12... a comparative decrease in C13/C12 & C14/C12 ratios provides definitive proof that mankind's burning of fossil-fuels is the source of the increased CO2 emissions... mass spectrometry shows a declining percentage of C13 & C14. This bottom half of

this pic from the IPCC AR4 WG1 report

shows the decreasing percentage of C13 in relation to increasing global emissions. The top half of that same pic shows something we haven't even discussed... another aspect proof, as oxygen levels are decreasing due to fossil-fuel burning.

Edited May 28, 2012 by waldo

[TimG]

Even there you are conceding far too much. #3 is a fact in that warming in itself would be climate change. #1 and #2, however, are theories that have yet to be proven.

Warming is "climate change" by definition since the "climate" is the average weather and increase in temperatures is a "change". You are technically correct to say that #1 and #2 are theories. I should have said the points were scientific theories well supported by evidence instead of calling them 'facts'. But that does not change the fact that we need to assume they are true and move on from there.

The real issue that we care about is what will be consequences of climate change. A lot of groups see CO2 mitigation as a vehicle to get governments to impose their preferred economic policies so they exaggerate the consequences and under estimate the costs. It is necessary to separate the exaggerations from the scientific evidence.

[bleeding heart]

You have not offered any evidence to support your assertion that spending more money before would have changed anything. I used to moonshot as an example of how technology cannot be rushed by government fiat.

But you haven't offered any evidence of your larger claim: that hindsight affords us a perspective that there is such a thing as temporal inevitablity. The moon landing could not have happned prior to 1969, for example.

This is actually something akin to fate that you're proposing here.

[Michael Hardner]

But you haven't offered any evidence of your larger claim: that hindsight affords us a perspective that there is such a thing as temporal inevitablity. The moon landing could not have happned prior to 1969, for example.

This is actually something akin to fate that you're proposing here.

Ooo... now THAT sounds like a substantial discussion. What about the possibility that temporal inevitability doesn't preclude some advantage to acting earlier. In the case of the Moonshot, to provide a technological template for industry so that advantages could be realized earlier and/or stuffin' it in the Russkies faces...

A few less years of warming might be a good thing, assuming warming is a bad thing.

[wyly]

Warming is "climate change" by definition since the "climate" is the average weather and increase in temperatures is a "change". You are technically correct to say that #1 and #2 are theories. I should have said the points were scientific theories well supported by evidence instead of calling them 'facts'. But that does not change the fact that we need to assume they are true and move on from there.

A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing....theories are accepted to be true until proven false.

[TimG]

But you haven't offered any evidence of your larger claim: that hindsight affords us a perspective that there is such a thing as temporal inevitablity. The moon landing could not have happned prior to 1969, for example.

There are two aspects to the problem: economics and technology.

On economics:

In the 60s the US spent about 4% of the federal budget on the program.

In 2010 dollars the US budget was $1325.53 billion in 1965.

In 2010 dollars the US budget was $16.29 billion in 1900.

So 4% of the government budget in 1965 would have been 330% of the federal spending in 1900.

The difference is because the US population and GDP per person grows over time.

So it is clear that no matter how much the US government might have wanted to go to the moon in 1900 the government simply did not have the money that it had in the 60s so we can be absolutely certain that any such program would be a failure due to lack of funding (if we assume that 4% of 1965 budget was the amount that needed to be spent).

In fact, if you started the process in 1948 the same spending would consume 10% of the budget instead of 4% - within the realm of possibility now but large enough that it would likely never get funding.

On technology:

The space program depended on many technological advancements that simply did not exist in 1900. The most obvious one being flight (powered flight did not show up until 1903).

In many cases, these advancements were unanticipated discoveries that one cannot plausibly claim that the government could have accelerated their accidental discovery by throwing money at unrelated problems.

In summary, between economics and technology there is no way the moonshot could have happened sooner than the 60s. A earlier decision to spend money might have brought it forward by a few years but no more than that.

Edited May 28, 2012 by TimG

[Michael Hardner]

There are two aspects to the problem: economics and technology.

On economics:

In the 60s the US spent about 4% of the federal budget on the program.

In 2010 dollars the US budget was $1325.53 billion in 1965.

In 2010 dollars the US budget was $16.29 billion in 1900.

So 4% of the government budget in 1965 would have been 330% of the federal spending in 1900.

The difference is because the US population and GDP per person grows over time.

Whaaaaaaat ?

The space program was around in 1900 ? 1.3 Trillion 2010 dollars represented 4% of the budget in 1965 ?

In summary, between economics and technology there is no way the moonshot could have happened sooner than the 60s. A earlier decision to spend money might have brought it forward by a few years but no more than that.

I find this interesting, and I'm curious if you have some key technologies in mind that needed to be discovered/tested - presumably in the 1950s - for the moon shot to happen. Teal's silicon transistor was tested in 1954.

[Keepitsimple]

A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing....theories are accepted to be true until proven false.

Finally Wyly, you're climbing down from the haughty alarmist viewpoint. Your definition is accurate and just validates that APG is not a genuine theory - as your classic definition would demand. There has been no "repeated testing" - because our Climate system cannot be tested. We simply have computer models that, with the data that is input, can't account for "excess warming" other than by modifying the amount of CO2 that is input. Computer models - that's all we've got. Garbage in - garbage out. Given the complexity, the best testing is observational. CO2 shot upwards during the post-war industrial boom of 1940 to 1979 - yet temperatures dropped. CO2 is still rising, yet temperatures are staying flat. That alone should remove the hubristic attitude that humans have the largest influence on Climate Change, and not natural factors.

Edited May 28, 2012 by Keepitsimple

[Michael Hardner]

Computer models - that's all we've got.

KIS - not exactly true. The GHG effect is also pretty well understood.

One of the top reputable skeptics, Richard Lindzen, has his views summarized as thus:

According to an April 30, 2012 New York Times article, "Dr. Lindzen accepts the elementary tenets of climate science. He agrees that carbon dioxide is a greenhouse gas, calling people who dispute that point “nutty.” He agrees that the level of it is rising because of human activity and that this should warm the climate." However, he believes that decreasing tropical cirrus clouds in a warmer world will allow more longwave radiation to escape the atmosphere, counteracting the warming.

[bleeding heart]

On technology:

The space program depended on many technological advancements that simply did not exist in 1900. The most obvious one being flight (powered flight did not show up until 1903).

In many cases, these advancements were unanticipated discoveries that one cannot plausibly claim that the government could have accelerated their accidental discovery by throwing money at unrelated problems.

In summary, between economics and technology there is no way the moonshot could have happened sooner than the 60s. A earlier decision to spend money might have brought it forward by a few years but no more than that.

Yes, and the moon landing isn';t the greatest analogy...but I was addressing the analogy already present.

As it stands, I completely agree that it was not possible in 1900.

but you said it had to be 1969. that's far too precise.

If, for political or financial reasons, it had occurred in 1972...your argument then must be (according to the way you set it out earlier, and so declaratively) that it could not have occurred until 1972.

Even though, in an alternate reality (ie the one we're currently inhabiting) it occurred three years earlier.

Now, there's a slight caricature of a Taoist sensibility, in which we can claim that things are as they must be, by definition that they are as they are...but I disagree with that, and I don't think it's where you're going with this.

[TimG]

The space program was around in 1900 ? 1.3 Trillion 2010 dollars represented 4% of the budget in 1965 ?

1.3 trillion is the 1965 budget in 2010 dollars - the actual dollars spent were less due to inflation. 4% of that is $52 billion in 2010 dollars which far exceeds the 1900 budget in 2010 dollars.

I find this interesting, and I'm curious if you have some key technologies in mind that needed to be discovered/tested - presumably in the 1950s - for the moon shot to happen.

The transistor is one of them. The moonshot needed to minimize mass. But there are many other related to production techniques because the rockets required precise engineering to build the parts. 60 years of experience in factories (including a lot of it trial and error) is near impossible to replicate by government fiat. Edited May 28, 2012 by TimG

[bleeding heart]

That alone should remove the hubristic attitude that humans have the largest influence on Climate Change, and not natural factors.

First of all, human beings are "natural factors," and your formulation that sets us magically apart, as determined by the Bible, ultimately, is itself massive hubris.

Second, it's no more hubristic then my wild theories about human beings flying in the air in incredibly heavy machines, landing robots on Mars, and keeping oruselves alive through medical technology and ever-expanding biological knowledge. Arrogant of me, i know, but I honestly think these are objectively real things.

[TimG]

Yes, and the moon landing isn';t the greatest analogy...but I was addressing the analogy already present.

It is the analog most used by renewable advocates to justify increased government spending. This discussion started that because someone claimed that renewable technology would be here today if only the government had spent more money 30 years ago. The moonshot example is excellent illustration of how governments are limited in the amount of innovation that they can stimulate.

but you said it had to be 1969. that's far too precise.

I never said that. In fact I didn't even use 1969 in my posts because I had forgotten the exact date until you mentioned it,

My argument is governments do have the ability shift innovation forward by a few years if the prerequisite technologies already exist. But they have no influence beyond that. Spending more money on renewables 30 years ago would have made no difference to where we are today because the prerequisite technologies have not been found yet (e.g. a cheap battery that could be installed in every building like a furnace or stove).

Edited May 28, 2012 by TimG

[bleeding heart]

My argument is governments do have the ability shift innovation forward by a few years if the prerequisite technologies already exist.

Prerequisite technologies do not blossom into being at the "right" time.

But they have no influence beyond that. Spending more money on renewables 30 years ago would have made no difference to where we are today because the prerequisite technologies have not been found yet.

It takes money and effort to discoiver the requisite technologies.

??

[TimG]

It takes money and effort to discoiver the requisite technologies.

I am assuming that the government is always pumping money into R&D to support general innovation. The question is whether large amounts of additional money can speed up the appearance of a politically useful technology. In the 60s the answer was yes when it came to the moonshot and there are other situations with similar circumstances. However, as general rule this *extra* dose of government money can only make a difference at the right time because of the need for prerequisite technologies. Edited May 28, 2012 by TimG

[Michael Hardner]

1.3 trillion is the 1965 budget in 2010 dollars - the actual dollars spent were less due to inflation. 4% of that is $52 billion in 2010 dollars which far exceeds the 1900 budget in 2010 dollars.

Pretty low budget, interestingly enough.

The transistor is one of them. The moonshot needed to minimize mass. But there are many other related to production techniques because the rockets required precise engineering to build the parts. 60 years of experience in factories (including a lot of it trial and error) is near impossible to replicate by government fiat.

Very interesting, thanks.

[wyly]

- because our Climate system cannot be tested.[/b] We simply have computer models that, with the data that is input, can't account for "excess warming" other than by modifying the amount of CO2 that is input. Computer models - that's all we've got. Garbage in - garbage out.

computer models put men on the moon, computer models put robotic craft on mars...computer models verify many, many things that cannot the tested in a laboratory...the laws of physics determine how chemicals will and must react every time there is no variance, each element has properties that it must follow and cannot behave differently merely because you're viewpoint is based on an inadequate understanding of science...this is as basic as it gets only in the denier world do chemical properties gain magical properties that do not exist...like math, chemistry can all be done on paper/computer with highly accurate results...

Given the complexity, the best testing is observational. CO2 shot upwards during the post-war industrial boom of 1940 to 1979 - yet temperatures dropped. CO2 is still rising, yet temperatures are staying flat. That alone should remove the hubristic attitude that humans have the largest influence on Climate Change, and not natural factors.

again your understanding is based on a flawed knowledge, this time of data collection and interpretation, long term trend, mean, etc...in my day this was 8th grade science, wyly Jr just studied these concepts/tools in the 6th grade...

[waldo]

Simple, aside from your standard repeat pattern of failing to provide any substantiation to your statements:

We simply have computer models that, with the data that is input, can't account for "excess warming" other than by modifying the amount of CO2 that is input. Computer models - that's all we've got. Garbage in - garbage out.

your wanton disregard for overwhelming empirical evidence has been noted many times over. Even if one accepts your banal, simplistic take on climate models... you have been repeatedly challenged to put up a "fake skeptic" model that can account for the increased warming, sans CO2. Is there a problem you continue to fail to present your alternative model(s)?

you keep repeating the same nonsense... the same idiocy!

=> Simple, your "lack of warming" nonsense - (notwithstanding your purposeful cherry-picking and propensity towards short-term trending... along with basic trending fundamentals you still can't grasp):

If you consider that the average global temperature has remained virtually unchanged over the past 15 years

no, it most certainly has not - you are incorrect and purposely choosing to misinform

Not ended... not slowed... and not natural

5 major global temperature data sets - annual averages with natural influences removed;

=> Simple, your "GIGO climate models" nonsense:

notwithstanding many MLW threads have brought forward significant model-to-observation correlations, as stated, you continue to ignore overwhelming empirical evidence... along with the following inconvenient truth that belies your fake skeptics "models only" talking point:

... without the models:

...

the CO2 problem in 6 easy steps

... without relying on climate models

The CO2 problem in 6 easy steps

We often get requests to provide an easy-to-understand explanation for why increasing CO2 is a significant problem without relying on climate models and we are generally happy to oblige. The explanation has a number of separate steps which tend to sometimes get confused and so we will try to break it down carefully.

Step 1: There is a natural greenhouse effect.

The fact that there is a natural greenhouse effect (that the atmosphere restricts the passage of long wave (LW) radiation from the Earth’s surface to space) is easily deducible from i) the mean temperature of the surface (around 15ºC) and ii) knowing that the planet is roughly in radiative equilibrium. This means that there is an upward surface flux of LW around [tex]\sigma T^4[/tex] (~390 W/m2), while the outward flux at the top of the atmosphere (TOA) is roughly equivalent to the net solar radiation coming in (1-a)S/4 (~240 W/m2). Thus there is a large amount of LW absorbed by the atmosphere (around 150 W/m2) – a number that would be zero in the absence of any greenhouse substances.

Step 2: Trace gases contribute to the natural greenhouse effect.

The fact that different absorbers contribute to the net LW absorption is clear from IR spectra taken from space which show characteristic gaps associated with water vapour, CO2, CH4, O3 etc (Harries et al, 2001; HITRAN). The only question is how much energy is blocked by each. This cannot be calculated by hand (the number of absorption lines and the effects of pressure broadening etc. preclude that), but it can be calculated using line-by-line radiative transfer codes. The earliest calculations (reviewed by Ramanathan and Coakley, 1979) give very similar results to more modern calculations (Clough and Iacono, 1995), and demonstrate that removing the effect of CO2 reduces the net LW absorbed by ~14%, or around 30 W/m2. For some parts of the spectrum, IR can be either absorbed by CO2 or by water vapour, and so simply removing the CO2 gives only a minimum effect. Thus CO2 on its own would cause an even larger absorption. In either case however, the trace gases are a significant part of what gets absorbed.

Step 3: The trace greenhouse gases have increased markedly due to human emissions

CO2 is up more than 30%, CH4 has more than doubled, N2O is up 15%, tropospheric O3 has also increased. New compounds such as halocarbons (CFCs, HFCs) did not exist in the pre-industrial atmosphere. All of these increases contribute to an enhanced greenhouse effect.

Step 4: Radiative forcing is a useful diagnostic and can easily be calculated

Lessons from simple toy models and experience with more sophisticated GCMs suggests that any perturbation to the TOA radiation budget from whatever source is a pretty good predictor of eventual surface temperature change. Thus if the sun were to become stronger by about 2%, the TOA radiation balance would change by 0.02*1366*0.7/4 = 4.8 W/m2 (taking albedo and geometry into account) and this would be the radiative forcing (RF). An increase in greenhouse absorbers or a change in the albedo have analogous impacts on the TOA balance. However, calculation of the radiative forcing is again a job for the line-by-line codes that take into account atmospheric profiles of temperature, water vapour and aerosols. The most up-to-date calculations for the trace gases are by Myhre et al (1998) and those are the ones used in IPCC TAR and AR4.

These calculations can be condensed into simplified fits to the data, such as the oft-used formula for CO2: RF = 5.35 ln(CO2/CO2_orig) (see Table 6.2 in IPCC TAR for the others). The logarithmic form comes from the fact that some particular lines are already saturated and that the increase in forcing depends on the ‘wings’ (see this post for more details). Forcings for lower concentration gases (such as CFCs) are linear in concentration. The calculations in Myhre et al use representative profiles for different latitudes, but different assumptions about clouds, their properties and the spatial heterogeneity mean that the global mean forcing is uncertain by about 10%. Thus the RF for a doubling of CO2 is likely 3.7±0.4 W/m2 – the same order of magnitude as an increase of solar forcing by 2%.

There are a couple of small twists on the radiative forcing concept. One is that CO2 has an important role in the stratospheric radiation balance. The stratosphere reacts very quickly to changes in that balance and that changes the TOA forcing by a small but non-negligible amount. The surface response, which is much slower, therefore reacts more proportionately to the ‘adjusted’ forcing and this is generally what is used in lieu of the instantaneous forcing. The other wrinkle is depending slightly on the spatial distribution of forcing agents, different feedbacks and processes might come into play and thus an equivalent forcing from two different sources might not give the same response. The factor that quantifies this effect is called the ‘efficacy’ of the forcing, which for the most part is reasonably close to one, and so doesn’t change the zeroth-order picture (Hansen et al, 2005). This means that climate forcings can be simply added to approximate the net effect.

The total forcing from the trace greenhouse gases mentioned in Step 3, is currently about 2.5 W/m2, and the net forcing (including cooling impacts of aerosols and natural changes) is 1.6±1.0 W/m2 since the pre-industrial. Most of the uncertainty is related to aerosol effects. Current growth in forcings is dominated by increasing CO2, with potentially a small role for decreases in reflective aerosols (sulphates, particularly in the US and EU) and increases in absorbing aerosols (like soot, particularly from India and China and from biomass burning).

Step 5: Climate sensitivity is around 3ºC for a doubling of CO2

The climate sensitivity classically defined is the response of global mean temperature to a forcing once all the ‘fast feedbacks’ have occurred (atmospheric temperatures, clouds, water vapour, winds, snow, sea ice etc.), but before any of the ’slow’ feedbacks have kicked in (ice sheets, vegetation, carbon cycle etc.). Given that it doesn’t matter much which forcing is changing, sensitivity can be assessed from any particular period in the past where the changes in forcing are known and the corresponding equilibrium temperature change can be estimated. As we have discussed previously, the last glacial period is a good example of a large forcing (~7 W/m2 from ice sheets, greenhouse gases, dust and vegetation) giving a large temperature response (~5 ºC) and implying a sensitivity of about 3ºC (with substantial error bars). More formally, you can combine this estimate with others taken from the 20th century, the response to volcanoes, the last millennium, remote sensing etc. to get pretty good constraints on what the number should be. This was done by Annan and Hargreaves (2006), and they come up with, you guessed it, 3ºC.

Converting the estimate for doubled CO2 to a more useful factor gives ~0.75 ºC/(W/m2).

Step 6: Radiative forcing x climate sensitivity is a significant number

Current forcings (1.6 W/m2) x 0.75 ºC/(W/m2) imply 1.2 ºC that would occur at equilibrium. Because the oceans take time to warm up, we are not yet there (so far we have experienced 0.7ºC), and so the remaining 0.5 ºC is ‘in the pipeline’. We can estimate this independently using the changes in ocean heat content over the last decade or so (roughly equal to the current radiative imbalance) of ~0.7 W/m2, implying that this ‘unrealised’ forcing will lead to another 0.7×0.75 ºC – i.e. 0.5 ºC.

Additional forcings in business-as-usual scenarios range roughly from 3 to 7 W/m2 and therefore additional warming (at equilibrium) would be 2 to 5 ºC. That is significant.

Q.E.D.?

Given the complexity, the best testing is observational. CO2 shot upwards during the post-war industrial boom of 1940 to 1979 - yet temperatures dropped. CO2 is still rising, yet temperatures are staying flat. That alone should remove the hubristic attitude that humans have the largest influence on Climate Change, and not natural factors.

=> Simple, your CO2-to-temperature correlation nonsense:

Simple...

-

firstly

, we have you starting off presuming to offer a contradictory premise where you, with the grandest lack of specificity, labeled 1940s-1970s global cooling as... "significant"... particularly in relation to rising CO2 levels. Of course, as is the fake skeptic way, you neither qualified "significant", nor did you even attempt to attribute said "significant" cooling... or what brought us out of the "significant" cooling. Of course I was quite content to highlight your consistency with past MLW threads where you have shown no understanding of temperature trending, where the actual degree of "significant" cooling amounted to only 0.1°C cooling over the entire 1940-1975 period, where you avoided any correlation of temperature to total forcings, where you avoided any causal attribution for either the "significant" 0.1°C cooling over the entire 1940-1975 global cooling or the post-1975 0.2°C

per decade

warming. In contrast to you, I actually offered causal ties to both the 1940-1975 & post-1975 periods... you could actually take a stab at attempting to be a real skeptic by assigning your own inferred alternative attributions. You could that, right?

notwithstanding Simple's keen eyeball prowess in presuming to interpret a historical CO2-temperature correlation from a series of image map presentations on temperatures alone...

- historical trends in CO2 concentrations and temperature, on a geological and recent time scale (Vostok, Law Dome DE08, DE08-2, and DSS ice cores, SIO, CRUTEM3v) -

here

:

- CO2 concentration and temperature trend overlay ((Annual atmospheric carbon dioxide (

NOAA

) and annual global temperature anomaly (

GISS

)) from 1964 to 2008) -

here

:

[waldo]

One of the top reputable skeptics, Richard Lindzen, has his views summarized as thus:

at some point you will realize... you will accept... Lindzen is a charlatan with a "reputation" that was built from his early long past work.

[wyly]

However, here Carter presents a fairly level-headed article. However, I disagree with his assertion that we should deal with the real consequences posed by climate change as they come along rather than prevent our contributions to it (assuming human contribution of CO2 is significant driver of recent climate change). That's like saying we should deal with the consequences of hole in the ozone as they come along.

Kinda like the weather. Nobody can exactly predict what the climate will be in a given region 50 years from now, but they can make an educated estimation, like weather.

it's a head in the sand approach...today's climate is affected by events decades ago, the climate 50 or 100 yrs from now will be effected by what we do or not do today...seems to me this is similar to preventative healthcare, it's more prudent and less expensive to avoid future problems early...

[Keepitsimple]

KIS - not exactly true. The GHG effect is also pretty well understood.

One of the top reputable skeptics, Richard Lindzen, has his views summarized as thus:

Michael...... the GHG effect is only one small component of the debate. CO2 is only a miniscule portion of our GHG umbrella - roughly 4 molecules out of 10,000.....with water vapour being by far the most relevant. So I grant you that the GHG effect is pretty well tested or agreed upon as a theory......but the role that CO2 actually plays along with all the other feedback variables, solar and orbit variations.....that's why I say there has been no repeated testing - only computer modeling.

[Michael Hardner]

at some point you will realize... you will accept... Lindzen is a charlatan with a "reputation" that was built from his early long past work.

Are there, in your opinion, ANY climate scientists who are reputable skeptics then ?

I have my sources, and they abide by his credentials.

[Michael Hardner]

that's why I say there has been no repeated testing - only computer modeling.

Ok, well I have the example of the skeptic who abides by the standard orthodoxy (for lack of a better word) and you have TimG.

Your choice at some point is scientific institutions, or the abyss of crackpots and self-promoters. TimG is an anomaly in that his views are quite middle-of-the-road but he discredits scientific institutions, but he does also have conventional views.