BTW, Demonstrable AGW = 0. Again.

[tomclarke]

To say nothing of the extented growing season at northern lattitudes, whole regions opened up to agriculture not now viable. They never ran the orchards farther north in China than during the MWP.

Choff - I am not arguing whether we would eventually be better or worse off at a lower or higher temp. I don't know. I doubt anyone does.

I am arguing that nations would change, mass migration of people would be needed. Mass changes in land use.

Think about the political disruption and danger of war
Think about the economic disruption.

The main argument I hear against AGW science is that it results in inconvenient push to move to lower carbon economy, that is a small extra economic burden on society which is considered intolerable.

how much more intolerable would be the cost of this mass migration, nation moving, land use change be?

It seems some people will filter this stuff to consider only one side of the equation.

BTW - this is not comparable with MWP. That might be an average of +0.5C globally, locally higher or lower because uneven. We are talking here about +5C globally, locally much higher (or lower) because uneven.

[Diogenes]

How do you figure that positive feedbacks do not result in ever increasing temperature? My understanding is that a positive feedback will cause a temperature increase until it is offset by some effect which will halt or neutralize it.

Stability, or lack of it is based on overall feedback.
"A positive feedback" does not mena the system as a whole has positive feedback.

I think you and I are interpreting these words differently. When I refer to "Positive feedback" I mean a total system wide positive feedback. Not one feedback effect among many.

In this case the feedbacks on the earth surface temperature include a factor of:
-5.5 W/Km^2.
In other words, for every degree K rise in temperature, the power lost from black body radiation increases by 5.5W.

Suppose you have a positive feedback from H2O of 2W/Km^2 and a forcing of 1W/m^2 from CO2.

Without the H2O effect the 1W/m^2 would combine with the -5.5W/Km^2 to give 0.18C temp rise.

With the H2O effect the overall feedback is still negative, but only -3.2W/Km^2.

So the temp rise is now 0.3C, and increase (or amplification) of slightly more than 50%.

Yes, about that C02 forcing you keep mentioning. From where do you get this number?

Basically there is a stabilising negative feedback from the black body radiation out, which increases as temperature increases.

If other effects are held stable, sure. An Increase in temperature would result in increased radiation, but I think you are oversimplifying by modeling the system as a black body with a fixed radiation emission. I think the system also varies in volume due to the atmosphere increasing in size with temperature.

I am vastly simplifying the system. But it would be strange indeed of energy lost from the earth to space did not go up with the earth temperature, whatever extra effects atmosphere adds. And indeed the climate modellers who have looked in detail at the effect of atmosphere find that the result is not that different from black body radiation, however the temperature is a bit lower than the surface temp.

The atmosphere is a glob of air. When you heat it, it expands. If I recall properly, it ought to expand by 1/273 per degree (C) of temperature increase. That works out to about another 15384615 cubic kilometers (per degree of Temperature increase) of additional volume with which to radiate away more heat. That in itself is another negative feedback mechanism. I would suppose it is a multiplier for the black body radiation negative feedback effect.

As long as total other feedback is less positive than this is negative the system will be stable, but with forcing inputs effectively amplified. I'll give you the math if you need it, it is simple.

Math is a great thing, but when you don't put in all the variables, your equation will be incomplete. That is what I think is happening with your's, and other's models. For example, water both absorbs and emits radiation in the spectrum as outlined by the chart I posted up thread, but I believe this chart is for molecular water. I do not believe this chart accurately represents the reflection characteristics of water in droplet form. (in air) I believe water in droplet form will reflect all spectra (to some extent) which possesses a wavelength shorter than double the diameter of the water droplet size.

Indeed my approximation is very incomplete. That is why atmosphee radiation balance have much more complex models. Droplets in air => cloud and they include this. You are right that things are more complex with clouds, and whether the effect is heating or colling depends on the height of the cloud.

If you read the detailed work (now quite old) from climate modellers on the effects of cluds you will get the full messy equations.

I have long been arguing that it isn't really necessary to look at their equations. If they were correct about the greenhouse effect for Carbon Dioxide, then the same effect would hold true for water vapor, which if it were true, would mean that the planet is an 800 degree inferno upon which nothing could live.

The fact that we are able to have a conversation is proof that they are wrong.

I believe this characteristic makes water far more reflective than is it's ordinary absorption spectrum. Does your model take this phenomena into account?

My model does not, but people who do this can accurately model clouds. the difficult issue is to determine how temperature affects cloud cover. But for typical cloud cover the basic relationships hols, it is just a slight modification.

Many's the time this summer when a cloud passed over me. With the 115 degree (Fahrenheit) heat we've been having, it was no revelation to me that clouds cause the underlying surface to become cooler. It would seem to me that with increased water density in air, it would be impossible to keep them from forming.

How can they argue that we won't get increasing cloud cover with increasing temperature? I'd like to see how they model clouds, especially the part where they dispense with the phenomena of their creation.

Show me your math. I think some of your assumptions regarding forcings and feedbacks are not accurate.

I'm not sure what you are asking for. The example above shows that a positive feedback can exist while the system as a whole stays stable. As for whether the overall feedbacks are negative well it is pretty clear that they are because we get small chnages in earth temperature not jumps. But to prove this you ned detaild quantitative values for all feedbacks, positive and negative.

I think the overall system feedback is negative. I think the negative fedbacks balance out the component positive feedbacks and the system achieves a somewhat stable equilibrium.

I think I've answered your original reason for disbelieving the climate science - that you could not see how the system could remain stable with positive feedback from H2O?.

If H20 was ONLY a positive feedback, I could not see how the system could remain stable. It is only by realizing that H20 is a net NEGATIVE feedback that any reconciliation with theory is possible. H20 flips from positive to negative.

Molecular water vapor in air produces the same greenhouse effect that CO2 produces, but more of it and better. But water vapor doesn't remain a vapor, it forms into droplets which do a better job of reflecting radiation than absorbing it, thus altering the energy balance towards the cooler.

But if you want me to write stuf down more formally as a heat balance equation I could?

Undoubtedly the inputs and outputs have to balance. I just don't think climate scientists are accurately describing the inputs and outputs. For example, do they model carbon dioxide on the night time side of the planet? Do they model it's absorption after the radiation has descended through some quantity of atmosphere on average?

What stops the planet from becoming surrounded by one giant continuous cloud?

All these effects, feedbacks and forcings, are for small peturbations approximately linear.

How can you say that the reflectivity of water is a SMALL perturbation? Is there a larger effect, other than perhaps the Sun itself? I would like to see you produce a list of effects ordered from the largest in magnitude down to barely significant.

You are misunderstanding. The issue is that extra CO2 in atmosphere makes a small change to what would be the case without the (extra) CO2. This small change is a peturbation in the heat balance, to track it you can treat the whole system as linear, because the changes are small. (1K is small compared with 250K). The overall effects of H2O can be much larger than the change as the result of increased CO2.

If I am understanding you correctly, you are describing the amplification effect of water vapor resulting in increased heat from C02 absorption. Interestingly enough, I just read a critique of this very theory today.
Of course, my argument is that H20 produces this effect from itself, and CO2 doesn't need to drive it. H20 can amplify it's own effect.

As above, a stable surface temperature results from forcings + feedbacks as long as the total feedbacks (including BB radiation - the big one) are negative. Adding a positive H2O feedback to the mix then amplifies the effect of forcings without leading to instability.

But it is my contention that Water flips from being a positive feedback effect, into a NEGATIVE feedback effect, because it forms clouds high in the sky that reflect a significant portion of radiation before it gets an opportunity to warm the atmosphere and the ground beneath the clouds.

Diffusion increases with temperature, and until clouds form, the diffusion and temperature produce a positive feedback effect which eventually becomes offset by the NEGATIVE effect created by denser cloud cover. At some point, the constant diffusion of water into the air results in a balance between heat absorption and radiation reflection. The system attains equilibrium because the opposing forces of positive and negative feedback cancel each other out.

Water is the dominate effect.

It is arguable that change in cload formation could make the overall effect negative. But you need evidence. The evidence (go read the literature) is against you on this.

And this I find particularly amusing. The best evidence that runaway greenhouse effect is not possible is the fact that we are alive. One doesn't need literature to convince us otherwise. If their theory were correct, we ought not be here. H20 does the same thing as CO2, but it does it far better, and there is a lot more of it.

Certainly whether clouds form at high or low altitudes is complex and as one type is positive the other negative whether cloud cover overall makes a positive or negative extra fedback is not going to be simple. However it can be possible to bound the overall effect (because we know what is max change in cloud cover over globe at differnet temps) even if all details are not known.

I'm afraid this is a "go read the literature" for more details.

I would like to see them explain cloud formation away. That would be a neat trick, for sure.

I think water in droplet form emits more than it does in molecular form because it creates trillions of parabolic reflectors which are structures that ought to reflect (to some degree) every wavelength within a range of double the droplet size.

This paper appears to support that contention.

I think what you mean is that clouds are more opaque (for given thickness) than air.

Opaque isn't an accurate description. Yes, they are opaque, but they are more than just opaque. They are reflective. They directly alter the energy balance by reflecting incoming radiation back out into space. What energy they absorb, they re-radiate at a higher elevation, thereby precluding it from reaching the ground, or if it does, in much reduced intensity.

Also whereas air has absorption (and therefore re-emmission) that peaks in infra-red, clouds absorb visible light equally. So they would be less good at providing GH effect. But actualy this has been calculatd, and it epends on the type (and height) of the clouds.

This stuff is basic and has ben worked out in detail by many people. Unless they are all in conspiracy together I would trust the generally accepted ideas.

Maybe, but history is littered with examples of individuals noticing characteristics of nature which others had missed. I suspect as more minds are brought to focus on the issue, some of their assumptions may not stand up to scrutiny.

You can see from the maths and figures that the mosquito does have a significant effect. If you diagree with the ballpark figures here we can go through the emmission characteristics at different frequencies and CO2/H2O absorption, and work out from first principles for a single atmospheric layer, then integrate over many layers. I'm prepared to do this at a very coarse level of approximation.

Best wishes, Tom

Now that sounds like a much better way to start. I would like to see how you obtain your figures for H20 and C02 radiation, and why you think the figure for H20 will be a sort of constant. I think it will increase and decrease in relation with the quantity of H20 in the air.

Umm, I think I left out /K. So the overall feedback for H2O is a difference in heat loss that varies linearly with temperature (for small chnages in temp). As you say, this is because greater temp => more H2O vapour => more GH effect => less heat loss.

Overall this is modelled (in linear approx) as x W/Km^2

where x detemined the size and sign of x determines whether positive or negative.

I do not know if the negative feedback characteristics of the droplet form of H20 are linear or not, but I would suspect they are non-linear. I think the confusion on this issue is the result of the fact that water in vapor form has a positive feedback effect, while water in droplet form has a negative feedback effect.

We are talking about two different effects for the same substance, and apparently people are ignoring the fact that the vapor form will eventually transform into the droplet form.

I think we are on the same page with some of this, but I think we deviate as to the direction and magnitude of the water negative feedback vector.

[Diogenes]

There are a multitude of models, but it looks to me like they all involve CO2 as a greenhouse gas and H2O as a multiplier. Even dismissing that, the mutability of the broader concept makes it scientifically untestable.

Those are two elements in the equation which are demonstrably and absolutely true. They rest on physics, not complex models. But there are many other strands of evidence of course.

CO2 as a greenhouse gas is solid physics. H2O as a warming multiplier rests on untested assumptions and grossly simplified models about cloud formation. The other strands of evidence suffer from poor quality control, and evasion of independent review.

I wonder if they model C02 by itself or as a component of gas at the bottom of an atmosphere of Oxygen and Nitrogen? Surely C02 is created near the surface, and I would suspect the bulk of it clings near the surface. Do they take into account the shading effect of all the other gases above it? Do they assume it is still absorbing energy on the night side of the planet?

I wonder what assumptions they use in determining the heat absorption characteristics of C02?

I also wonder why Water vapor doesn't give them a heart attack.

[Diogenes]

Those are two elements in the equation which are demonstrably and absolutely true. They rest on physics, not complex models. But there are many other strands of evidence of course.

CO2 as a greenhouse gas is solid physics. H2O as a warming multiplier rests on untested assumptions and grossly simplified models about cloud formation. The other strands of evidence suffer from poor quality control, and evasion of independent review.

Water vapour is clearly a feedback. The evidence it is positive is overwhelming, and does not depend on climate models.

And this is something I want to pound on. If Water Vapour is a positive feedback mechanism (which I agree that it is) Do you think it is only the black body radiation effect which is limiting our maximum temperature?

What effect opposes the positive feedback mechanism of water vapor? What prevents us from being an 800 degree Venus?

[choff]

To say nothing of the extented growing season at northern lattitudes, whole regions opened up to agriculture not now viable. They never ran the orchards farther north in China than during the MWP.

Choff - I am not arguing whether we would eventually be better or worse off at a lower or higher temp. I don't know. I doubt anyone does.

I am arguing that nations would change, mass migration of people would be needed. Mass changes in land use.

Think about the political disruption and danger of war
Think about the economic disruption.

The main argument I hear against AGW science is that it results in inconvenient push to move to lower carbon economy, that is a small extra economic burden on society which is considered intolerable.

how much more intolerable would be the cost of this mass migration, nation moving, land use change be?

It seems some people will filter this stuff to consider only one side of the equation.

BTW - this is not comparable with MWP. That might be an average of +0.5C globally, locally higher or lower because uneven. We are talking here about +5C globally, locally much higher (or lower) because uneven.

Assuming gradual changes modern civilization would have ample time to adapt. It wouldn't be an inconvienient cost, unless you have 10 or 20 Trillion bucks to spare, and the little people will be the ones expected to pay, certainly not the 1%.

Central American Indian civilizations are believed to have collapsed because of climate changes, even Rome and the Caliphate. These were naturally occuring climate cycles, and if we are entering a naturally occuring warming period, isn't spending money to fight nature like trying to stop global tidal cycles.

One arguement the pro warming lobby likes to use is that the Greenlanders had to keep the farm animals indoors 5 month of the year because it was too cold, but if that's true, then the other 7 months had to be productive enough to support fodder for the whole year.

That and according to Norwegian accounts the west coast of Greenland could be reached by travelling north then east. Try doing that today without an icebreaker, those wooden ships and iron men were tough! Sounds like a lot more than +5C to me.

[choff]

Just forgot to mention, we could spend all this money trying to turn back CO2 levels, and the first major volcanic eruption will render it all completely irrelevent.

[choff]

Here's the toughest selling point of all for global warming. The research is being paid for by banksters(essentially the 1%) via tax free trust foundations and the very UN they set up. They want the 99% to pay for the cleanup of CO2 that was created under their global economic management.

As reported in other threads, the 1% are sitting on anywhere from 20 to 32 Trillion in offshore tax havens, that should cover the cost nicely, the rest of us are a little tapped out right now.

So hit them up to pay for it all and stop bothering everybody else, but if you get too serious, you might find that these same CRU guys start saying its all a mistake and everythings peachy with global temp.

If they don't, if the problem is for real, you will also discover that they already have a plan to deal with global warming, it doesn't involve them shelling out one penny. I've seen quotes from these Club of Rome types saying humanity is no more valuable than slugs and snails and we should reduce it by 94%, not them of course. At the very least they want to hit the 99% with carbon taxes and carbon currency, do you think they really care about mass migration and hardships incurred.

People have reasonable grounds for suspicion.

[paperburn1]

IMHO the toughest selling point of all for global warming is I will be long dead before it affects me.

[palladin9479]

IMHO the toughest selling point of all for global warming is I will be long dead before it affects me.

Well the world climate is always changing, though the change is often slow with sudden small bursts. That's why everyone's freaking out now, they thing this is some sudden change and not realizing that it's been changing for centuries with little ups and downs. It'll get hotter and eventually it'll get colder until it hits another ice age, then it'll get warmer again. We might not even be around as a species by the time that happens.

The scales involved here dwarf humanity so severely, it's impossible not to feel like an ant when thinking about it.

[GIThruster]

Here's the toughest selling point of all for global warming. The research is being paid for by banksters(essentially the 1%) via tax free trust foundations and the very UN they set up. They want the 99% to pay for the cleanup of CO2 that was created under their global economic management.

More than 99.999% of the research is paid for with public funds. This is the reason we have a problem. Huge numbers of people with reputations as real scientists have landed vast amounts of money in the form of government grants monies, to promote this myth, be it fact or fiction. All the people getting all this money have a vested interest to "show" there is a problem, whether there is a problem or not. The vast majority of these folks are academics that live in urban environments and don't drive but tiny distances it at all, so they are not directly affected by the sanctions, carbon credits, escalating fuel prices, etc. that they are promoting.

Note again I am not saying we don;'t have a problem with global warming. I don;t know because there is just not enough evidence. Arguments for and against seem to me week, and we could have real answers if we could launch a sat or two. The problem that we know we have is this invasion of politics into science and the prostitution this brings.

[tomclarke]

CO2 as a greenhouse gas is solid physics. H2O as a warming multiplier rests on untested assumptions and grossly simplified models about cloud formation. The other strands of evidence suffer from poor quality control, and evasion of independent review.

Water vapour is clearly a feedback. The evidence it is positive is overwhelming, and does not depend on climate models.

And this is something I want to pound on. If Water Vapour is a positive feedback mechanism (which I agree that it is) Do you think it is only the black body radiation effect which is limiting our maximum temperature?

What effect opposes the positive feedback mechanism of water vapor? What prevents us from being an 800 degree Venus?

Well, BB radiation increases with temperature and thus is a negative feedback. It is larger than any other feedback at -5.5W/Km^2.

So yes, without this temperature would not stabilise. But hotter things radiating more heat is indeed the normal mechanism whereby whatever the other heat inflows objects equilibrate to a given fixed temperature, don't you think?

if we had positive feedbacks totalling larger than 5.5W/Km^2 then we would have a runaway problem (until the feedbacks saturated, as they tend to). But the feedbacks we know are all a good deal smaller than this.

[tomclarke]

I think you and I are interpreting these words differently. When I refer to "Positive feedback" I mean a total system wide positive feedback. Not one feedback effect among many.

The system as a whole (any system) has in general multiple feedbacks some positive, some negative. These all add together. If the sum is negative you are OK. Obviously, the sum (positive or negative) does not depend on any single feedback. So when we say CO2 feedback is positive we mean that it makes a positive contribution to the total, which may be positive or negative.

Yes, about that C02 forcing you keep mentioning. From where do you get this number?

There are many refs on the web. It is standard physics to compute, but tricky because you have to integrate over all the layers of teh atmosphere, deal deparately with every different wavelength, look at solar irradiance spectrum to determine what weight to give to each wavelength. But it is solid physics and does not depend on GCMs or temperature measurements.

here is wikipedia, for a very simple approx intro without proof:
http://en.wikipedia.org/wiki/Radiative_ ... pheric_gas

IPCC AR4 puts the combined effect of CO2 & other GHGs as a forcing of +2.3W/m^2K between 1750 and 2007. This is mostly CO2 (see graphs) and corresponds to CO2 increase a little less than 2X. So my ballpark figure of 2W/m^2K for X2 incraese was a bit low.
http://www.ipcc.ch/publications_and_dat ... n-and.html
If you want a detailed derivation of the CO2 figure, and others, here is a 1998 reference giving 2.25:
http://www.agu.org/pubs/crossref/1998/98GL01908.shtml
the detailed figure is affected by things like distribution of aerosols at different levels in atmosphere, and has some uncertainty attached (IPCC AR4 2007 gives bounds of 2.07 to 2.53)

Note that the values calculated increase with time because of increased CO2 in atmosphere.

All you have wanted to know about forcings (from 2006)

If you want a technical breakdown of how the calculations are done, and have time, you could read scienceofdoom

This website is hard work, partly because they work things out for themsleves and so make a lot of mistakes on the way to getting to a decent answer, but I rather like it. Their approach is look with interest at the various independent theories about climate science and deconstruct from each what is the real scientific argument. They never actually say that they agree with the "consensus", and appear sympathetic with the few non-conformists (Lindzen etc). However they do a good job of deconstructing the bad science in most of the independent papers quoted on the blogosphere, as well as pointing out that the various non-conformists all argue different and incompatible theories - so you can't add them all together as evidence against the consensus, you have to pick your one "best" which then invalidates the others.

The atmosphere is a glob of air. When you heat it, it expands. If I recall properly, it ought to expand by 1/273 per degree (C) of temperature increase. That works out to about another 15384615 cubic kilometers (per degree of Temperature increase) of additional volume with which to radiate away more heat. That in itself is another negative feedback mechanism. I would suppose it is a multiplier for the black body radiation negative feedback effect.

Yes, obviously viewing earth as a BB is only an approximation, but it works pretty well. Atmosperic expansion will modeify the result, but not by much.

I have long been arguing that it isn't really necessary to look at their equations. If they were correct about the greenhouse effect for Carbon Dioxide, then the same effect would hold true for water vapor, which if it were true, would mean that the planet is an 800 degree inferno upon which nothing could live.

The fact that we are able to have a conversation is proof that they are wrong.

OK - this is a common misconception.

Here is the key difference. H2O in atmosphere is in equilibrium with H2O on surface. So yes H2O adds many degrees of GW to earth (maybe 20 or something) but this effect is roughly constant, depending on temperature, so that higher temperature => more warming. However the positive feedback here is less than the overall negative feedback from BB radiation, as previously discussed.

CO2 is different because we can add CO2 to atmosphere and it stays there. There is no equilibrium. So the change due to ading CO2 matters. If we "added water" it would not matter, because within a few days the equilibrium would be reestablished by extra water vapour condensing.

Many's the time this summer when a cloud passed over me. With the 115 degree (Fahrenheit) heat we've been having, it was no revelation to me that clouds cause the underlying surface to become cooler. It would seem to me that with increased water density in air, it would be impossible to keep them from forming.

How can they argue that we won't get increasing cloud cover with increasing temperature? I'd like to see how they model clouds, especially the part where they dispense with the phenomena of their creation.

Clouds are complex, true. and they do modify things. But they do not have the dramatic cooling effect you think. In the DAY the cool. Which you notice. In the NIGHT they warm. actually you probably notice that too! The overall effect is complex and either positive or negative depending on where the clouds are.

You argue that hotter atmosphere => more clouds. That is also unclear. Measurements show that humidity increases with temperature, and relative humidity stays on average the same. but it is relative humidity that determines whether or not water condenses in air to make water droplets.

I think the overall system feedback is negative. I think the negative fedbacks balance out the component positive feedbacks and the system achieves a somewhat stable equilibrium.

there we agree, and it is waht I've been saying.

Undoubtedly the inputs and outputs have to balance. I just don't think climate scientists are accurately describing the inputs and outputs. For example, do they model carbon dioxide on the night time side of the planet? Do they model it's absorption after the radiation has descended through some quantity of atmosphere on average?

What stops the planet from becoming surrounded by one giant continuous cloud?

I think I'll have to refer you to the detailed science. But yes, the detailed calculations deal with day/night, different latitudes, integrates over atmospheric layers. This science has been refined over 50 years. It would be strange if it were not pretty good by now. Also, you would expect any obvious problems to have been detected.

If I am understanding you correctly, you are describing the amplification effect of water vapor resulting in increased heat from C02 absorption. Interestingly enough, I just read a critique of this very theory today.
Of course, my argument is that H20 produces this effect from itself, and CO2 doesn't need to drive it. H20 can amplify it's own effect.

scienceofdoom does a good job of running through the science in most of the blog critiques of basics. They all turn out wrong. But seeing why this is so can get quite complex.

And, as above, the key issue is that H2O quickly equilibrates between surface water and atmospheric water vapour so that it does not drive anything - it acts as a feedback. It does amplify any other change. Also, it does contribute some large number of degrees (20C?) to overall warming. Without H2O the earth would be a much colder place. But we are concerned with changes to the existing balance from adding CO2, not the absolute value of warming from H2O. these are much smaller.

And this I find particularly amusing. The best evidence that runaway greenhouse effect is not possible is the fact that we are alive. One doesn't need literature to convince us otherwise. If their theory were correct, we ought not be here. H20 does the same thing as CO2, but it does it far better, and there is a lot more of it.

I hope the above answers your worry that H2O being a positive feedback, combined with H2O having a larger GH gas effect than anything else, would mean runaway temps. There is no such necessity.

I would like to see them explain cloud formation away. That would be a neat trick, for sure.

Cloud formation is pretty well understod - but it is very complex, and to first order RH stays constant with temp, so clouds form about the same amount. Now that is probably wrong, go read the literature. There is lots. Lindzen has his own whacky theory about GCRs and cloud formation. However other evidence does not seem to support this. GCRs appear to have a relatively small effect on cloud formation.

This stuff is basic and has ben worked out in detail by many people. Unless they are all in conspiracy together I would trust the generally accepted ideas.

Maybe, but history is littered with examples of individuals noticing characteristics of nature which others had missed. I suspect as more minds are brought to focus on the issue, some of their assumptions may not stand up to scrutiny.

I think you underestimate the number of minds that have studies all these issues in much gretaer detail than you or me.

Climate science basics have been taught for 30 years +. Believe you me, to teach something you have to understand it from first principles very well. Students ask difficult questions. And you ask yourself difficult questions when giving a lecture.

there are many uncertainties about climate science - but the basic science is well understood.

I do not know if the negative feedback characteristics of the droplet form of H20 are linear or not, but I would suspect they are non-linear. I think the confusion on this issue is the result of the fact that water in vapor form has a positive feedback effect, while water in droplet form has a negative feedback effect.

We are talking about two different effects for the same substance, and apparently people are ignoring the fact that the vapor form will eventually transform into the droplet form.

I think we are on the same page with some of this, but I think we deviate as to the direction and magnitude of the water negative feedback vector.

All thes effects are nonlinear, but for small chnages can be approximated as linear. We are talking small changes (1C/270C).

you are arguing that clouds have a different effect from water vapour. That is true, but it is not simple negative or positive as above. It has been investigated in detail and depends on the height of the cloud. Further, it is very unclear what happens to cloud cover as temperature increases. RH (experimentally) stays constant. But of course overall cloud may increase or decrease as second order effects change things, and equally clouds at different heights change things. This is a factor where you need very detailed models of the whole climate system. And there is much uncertainty. But the values computed for this change are all relatively small, though not insignificant.

[choff]

Here's the toughest selling point of all for global warming. The research is being paid for by banksters(essentially the 1%) via tax free trust foundations and the very UN they set up. They want the 99% to pay for the cleanup of CO2 that was created under their global economic management.

More than 99.999% of the research is paid for with public funds. This is the reason we have a problem. Huge numbers of people with reputations as real scientists have landed vast amounts of money in the form of government grants monies, to promote this myth, be it fact or fiction. All the people getting all this money have a vested interest to "show" there is a problem, whether there is a problem or not. The vast majority of these folks are academics that live in urban environments and don't drive but tiny distances it at all, so they are not directly affected by the sanctions, carbon credits, escalating fuel prices, etc. that they are promoting.


Note again I am not saying we don;'t have a problem with global warming. I don;t know because there is just not enough evidence. Arguments for and against seem to me week, and we could have real answers if we could launch a sat or two. The problem that we know we have is this invasion of politics into science and the prostitution this brings.

That and if you read the climategate emails they talk about having the Phd revoked for people who aren't helpful, or hiding evidence and manipulating data, how the models don't work but use them anyway, how to smear and intimidate and kill funding for scientists who disagree.

[tomclarke]

Here's the toughest selling point of all for global warming. The research is being paid for by banksters(essentially the 1%) via tax free trust foundations and the very UN they set up. They want the 99% to pay for the cleanup of CO2 that was created under their global economic management.

More than 99.999% of the research is paid for with public funds. This is the reason we have a problem. Huge numbers of people with reputations as real scientists have landed vast amounts of money in the form of government grants monies, to promote this myth, be it fact or fiction. All the people getting all this money have a vested interest to "show" there is a problem, whether there is a problem or not. The vast majority of these folks are academics that live in urban environments and don't drive but tiny distances it at all, so they are not directly affected by the sanctions, carbon credits, escalating fuel prices, etc. that they are promoting.


Note again I am not saying we don;'t have a problem with global warming. I don;t know because there is just not enough evidence. Arguments for and against seem to me week, and we could have real answers if we could launch a sat or two. The problem that we know we have is this invasion of politics into science and the prostitution this brings.

That and if you read the climategate emails they talk about having the Phd revoked for people who aren't helpful, or hiding evidence and manipulating data, how the models don't work but use them anyway, how to smear and intimidate and kill funding for scientists who disagree.

The political things is bad - but it cuts both ways. I agree some (not all) climate scientists have developed a defensive "us against them" mentality in which they are engaged in polemic argument. I regret this.

But it is easy to see why this happens when you read the vast amount of well-funded political and clearly false disinformation on the skeptic side.

If you had to compare unscientific behaviour and propoganda the anti-AGW polemicists are about 100X worse than the climate scientists. And you can see why, subjected to continuous personal attacks and scientific disinformation, some scientists reply in kind.

Having said that, the IPCC process is politicised, inevitably. And as a result IPCC summaries I would expect tend to be slightly biassed on the "AGW is high" side. Not much, because the scientific full reports are good science, and summarising a wide variety of scientists who have varying biasses and anyway are constrained by the science. But the summaries are written with politics in view and the whole process goes beyond science.

I reckon there is not much difference between the IPCC probabilities and reality. But the summaries tend to underestimate the real uncertainty which is carefully delineated in the IPCC scientific chapters. For example, it could be that rises in Anthropogenic aerosols have a forcing effect currently negatively almost as high as CO2 forcing positively. Is that good? Not really, because aerosols are predicted to reduce in 21C and whereas the large forcing effect of the CO2 must remain. I guess if true it means we could reduce global warming by continuing to use highly polluting industrial processes, but that would maybe be politically unnacceptable because of the immediate effect on health.

But the anti-AGW approach is to highlight uncertainty and assume therefore that AGW is not a problem, or that everything is uncertain. That is not rational. The certain parts of the equation show a potential very significant problem. There is then uncertainty that could make that mostly go away, or be very very bad. There is as much validity in worrying about the very very bad case as in hoping for the go away case.

[GIThruster]

The political things is bad - but it cuts both ways. I agree some (not all) climate scientists have developed a defensive "us against them" mentality in which they are engaged in polemic argument. I regret this.

But it is easy to see why this happens when you read the vast amount of well-funded political and clearly false disinformation on the skeptic side.

That's absurd, Tom. Seriously, get some facts. Almost all the money is on the side of the AGW people, and all of this is because of politics, not science. Furthermore, claiming that the anti-agw people are full of false claims when the demonstrated facts are that the AGW arguments have been demonstrated to be false again and again, and their proponents to be fraudulent, and collaborating together to make fraudulent arguments, is just absurd.

Likewise, your claims that the critical position is to "assume therefore that AGW is not a problem" is obviously not true. The anti-agw position has always been "show me". If you want to tax carbon and pretend it's a pollutant, if you want to drive energy prices so high that people can't heat their homes and the costs of all items in society skyrocket, if you want essentially to impoverish the middle class, then you darn well better have some evidence that shows this is necessary, and thus far, the AGW crowd has not come up with this.

And I will remind you one more time, this above, to deliberately force energy prices sky high in order to cut back on consumption, has been the plan for more than 25 years. When I was TAing Environmental Ethics at PSU, all of the texts we used explained this was the only way to stop the catastrophe facing the planet. Pretending the way you are that there is some neutral position, is ridiculous. You either believe that the science shows we need to take dramatic action, or you don't. People who haven;t looked at the evidence like yourself; believe we need to take dramatic action because that's what the pseudo-scientists, politicians and mass media have told you to believe. So gas is twice as much now as it was a couple years ago, heating oil is so expensive that people will be icy cold in their homes this winter, and every industrial process that dumps CO2 into the air is going to be taxed. The EPA has started treating CO2 as a toxin, and we're all going to pay.

All without evidence we could easily have, if we'd just launch the sat that was grounded during the Bush years.

The AGW people forced this issue without making a real scientific case, and because they knowingly forced people into an adversarial position, they never got their sat launched. What this does is promote more of the bullshit pseudo-science coming from both you and Diogenes, neither of which have a clue to what you speak--just like all the other clowns pretending they know what they're talking about.

You two are not part of the solution. You are the problem.