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Right. And we're not hosting an intergalactic kegger down here either. ... don't touch that blanket kid. It might have smallpox or Martian ebola.

increased CO2 absolutely increases temperature

CO2 absorption decreases logarithmically, and we're already at a level where increased levels of CO2 makes no real difference. Catastrophic AGW is not due to CO2-warming, it's due to (unknown and still falsifyable) positive feedbacks.

http://brneurosci.org/temperatures6.png

(from http://brneurosci.org/co2.html - first hit I got on google. Don't know what the rest of that page contains)

increased CO2 absolutely increases temperature

CO2 absorption decreases logarithmically, and we're already at a level where increased levels of CO2 makes no real difference. Catastrophic AGW is not due to CO2-warming, it's due to (unknown and still falsifyable) positive feedbacks.

http://brneurosci.org/temperatures6.png

(from http://brneurosci.org/co2.html - first hit I got on google. Don't know what the rest of that page contains)

I'm not sure about the wireless hacking from a laptop mentioned in TFS, but, as far as RF transmissions, these things can generate plenty of spread-spectrum modulation EMF when modulating the 240kHz signal carrier on wire.
There's a good discussion about eliminating ground loops so as to avoid broadcasting the signal as a source of interference at the Technical Library; I suppose one could always use an induction receiver to go the other direction, using a loop antenna. Obviously, modification of the above designs is needed for target frequency band. AM radio circuits might be a good place to start, too.
Actually, there are tons of good MW box loop designs that already go well below 240kHz; that page includes a calculator, and playing with some quick numbers suggests a 48cmX65cm frame [=56.5cm side length] for a 16-turn coil extending 21cm in length in parallel with four 470pF caps gives us resonance at 245kHz. Of course, with 20% tolerance ceramic discs, you may want to replace one of the 470's with a 4-40pF variable cap in parallel with anywhere from a 150pF to a 39pF paralleled with a 560pF, depending on how low or high the 470's are measuring.

[Disclaimer: I am an RF amateur.]

I'm not sure about the wireless hacking from a laptop mentioned in TFS, but, as far as RF transmissions, these things can generate plenty of spread-spectrum modulation EMF when modulating the 240kHz signal carrier on wire.
There's a good discussion about eliminating ground loops so as to avoid broadcasting the signal as a source of interference at the Technical Library; I suppose one could always use an induction receiver to go the other direction, using a loop antenna. Obviously, modification of the above designs is needed for target frequency band. AM radio circuits might be a good place to start, too.
Actually, there are tons of good MW box loop designs that already go well below 240kHz; that page includes a calculator, and playing with some quick numbers suggests a 48cmX65cm frame [=56.5cm side length] for a 16-turn coil extending 21cm in length in parallel with four 470pF caps gives us resonance at 245kHz. Of course, with 20% tolerance ceramic discs, you may want to replace one of the 470's with a 4-40pF variable cap in parallel with anywhere from a 150pF to a 39pF paralleled with a 560pF, depending on how low or high the 470's are measuring.

[Disclaimer: I am an RF amateur.]

:)

I guess you haven't tried verifying it yourself - by all means, please do.

AGW does not rest on CO2 absorption - that is logarithmic and at the levels we're at in modern times (280ppm+) the effect of a doubling or tripling will go unnoticed.

http://brneurosci.org/co2.html (fig. 4)

AGW rests on speculated positive feedbacks, and all the models assume these to be true in their calculations.

http://en.wikipedia.org/wiki/Effects_of_global_warming#Positive_feedback_effects

Those positive feedbacks have not been observed, on the contrary, at least one of the speculated feedbacks has instead been observed to be negative.

http://www.springerlink.com/content/m2054qq6126802g8/?p=e209f4ac50044f93a421b19e0a636d4b&pi=0

Thus, the existing AGW models have been falsified.

For more information, look up the "scientific method" and read some Popper.

In reality, the situation isn't urgent. It's well known that as more CO2 is added to the atmosphere, the approximate energy absorption and temperature rise is logarithmic in nature. There's a good discussion at: The Cold Facts About Global Warming. By the best current estimates, a doubling of CO2 concentration from current levels would result in less than a one deg. C increase in temperature - and that's without considering likely negative cloud feedback.

First you say the atmosphere is too complex to model, then cite an article that uses an even simpler model with its own projections. A bit of a double standard if you ask me.

But fine, let's go with it. What do the calculations regarding double CO2 actually say?

The net effect of all these processes is that doubling carbon dioxide would not double the amount of global warming. In fact, the effect of carbon dioxide is roughly logarithmic. Each time carbon dioxide (or some other greenhouse gas) is doubled, the increase in temperature is the same as the previous increase. The reason for this is that, eventually, all the longwave radiation that can be absorbed has already been absorbed. It would be analogous to closing more and more shades over the windows of your house on a sunny day -- it soon reaches the point where doubling the number of shades can't make it any darker.

So another way of looking at it is by thinking of adding blankets to your bed on a cold night: if you have no blankets, adding one will have a big effect. If you have a thousand blankets, adding another thousand will have an unmeasurably small effect.

Sounds right - or does it?

Well, the amount of energy absorbed by the entire atmosphere doesn't change much - I can grant that much. This is because as you get higher into the atmosphere, because of all the CO2 below you, there isn't much heat coming out for you to block further anyway - hence the extra blankets analogy - the extra blankets don't do much more.

However, the analogy is wrong.

The problem is, it is calculating the total absorption of the entire atmosphere and then calibrating it against the surface temperature changes (which is totally unrelated). It doesn't matter to us how much the total temperature of the atmosphere increases. What matters is how much the surface temperature increases, because that's where we live.

It mentions earlier:

It is generally accepted that the concentration of carbon dioxide in the atmosphere is already high enough to absorb almost all the infrared radiation in the main carbon dioxide absorption bands over a distance of only a few km

Let's say 5km of atmosphere is capable of absorbing 100% of the heat energy. If you double the CO2, then the same amount of energy is absorbed in the bottom 2.5km. If you double again, then the same amount of energy is absorbed in the bottom 1.25km.

If 1.25km of atmosphere absorbed 5km worth of heat, that's 4 times the amount of heat as before. As we double the CO2 concentration twice, the amount of CO2 is 4 times more.

In other words, the surface temperature increases mostly linearly. That the total atmospheric temperature increase is logarithmic because more and more of the upper atmosphere is getting colder is immaterial. We don't live there!

The article is intentionally confounding two unrelated concepts to fool you into believing it.

I say this because earlier in the article, it said

For radiation from the sun, this theory predicts that increased CO2 would cause cooling in the upper atmosphere and warming in the lower atmosphere

So they know this, yet still manage to overlook it in their model.

Oh, and since we know for a fact that CO2 traps heat, you also need to explain why increased CO2 levels *aren't* causing any warming ... because only the first 20 to 80 ppm or so are really noticeable, since CO2 absorption is logaritmic.

http://brneurosci.org/temperatures6.png

Oh boy. Okay, before the Industrial Revolution CO2 levels where around 260 - 280 ppm for millenia. Since then CO2 levels have risen to above 380. Looking at the graph, that's a roughly 2 Kelvin increase from CO2 alone, not counting positive feedback through water vapor. And that is noticeable. Oh BTW, CO2 levels are rising exponentially, so that compensates for your logarithm.

Oh, and since we know for a fact that CO2 traps heat, you also need to explain why increased CO2 levels *aren't* causing any warming ... because only the first 20 to 80 ppm or so are really noticeable, since CO2 absorption is logaritmic.

http://brneurosci.org/temperatures6.png

Detailed global circulation models that predict climate accurately are still young.

No, they are nonexistent. There are no models that accurately predict climate.

However, the physics of CO2 in the atmosphere is well understood.

Yes, such as the fact that Earth's current concentration of CO2 is already near its asymptote for heat absorption, and increasing -- even doubling -- the amount of atmospheric CO2 will make a difference that is very near zero.

Do we keep on adding more CO2 to the atmosphere as if none of those effects will happen? Or do we change course?

Considering that the only way to "change course" involves killing hundreds-of-millions to billions of human beings, and condemning the rest to a pre-Industrial-age existence with all of its attendant poverty and disease, I vote for the former.

There is simply NO way to avoid adding CO2 to the atmosphere without destroying civilation. And it won't do a damn thing to global temperatures, since those are caused by changes in solar radiation, not by carbon dioxide.

Interesting link. Though the author makes some bad assumptions. According to the data presented on that page most wavelengths of IR are still absorbed by water vapor. And indeed CO2 has a very narrow absorption spectrum compared to water. http://brneurosci.org/spectra.png

The big mistake that I see is that the author assumes that since water has a high turnover rate in the atmosphere that it is not as significant. It is actually more significant because the largest amounts of energy released from water heating all the O2 and N2 is in the transition back to liquid water from water vapor. In fact, While water vapor makes up only 4% of the atmosphere it absorbs most of its energy while it is in a liquid state in the oceans only releasing excess energy into the air.

If you could get bodies of water to form across the equator of mars you could heat the planet much more quickly than you coan with gass alone.
I suspect that filling a water cistern and never using it does more to reduce global warming than shutting down a coal power plant.

Re. http://brneurosci.org/co2.html

Fig #2 is obviously not correctly done!

Note my notation. I'm going to compute some weights and one way would be to show this as a vector: W(O2, H2O, CO2) = (blah, blah, blah). I didn't use this notation. I instead used W(O2), W(H2O) and W(CO2) and in some cases varied some of these weights to illustrate the effect it has. The notational change would make what I'm writing more rigerous but it should be clear anyways... and the non-vector notation is the one most often used anyways.

There are two problems with this. (at least)

1. In order to add these effects together one needs to weight the concentrations of the various gases. Oxygen is at 21% so its absorbtion at the three (3) spikes shown will contribute most of the total effect at these wave lengths.

H2O varies a lot! It is also not found in significant quantites above the tree line. At high elevation its is practically non-existant because its absolute concentration drops almost to zero as the temperature drops to the freezng point. This is the dew point curve. At high latititude it is practically non-existant. This is why Antarctica is the dryest continent. In the tropics and sub-tropics for instance it will be concentrated at levels above 4% which is 40,000 PPM. Most of the surface area of the planet is at low latitude.

One needs to contour the average water vapour concentrations and integrate the effect and this is very complex.

CO2 is distributed throughout the atmosphere just as O2 is. But its concentration is at about 370 PPM.

So we have O2 at 210,000 ppm, H20 at 40,000 ppm (variable from 0.00 to upwards of 80,000) and CO2 at 370 ppm

The weights are thus 210000/(210000+40000+370), 40000/(210000+40000+370) and 370/(210000+40000+370)

This is ignoring the wide H2O distribution which needs to be integrated and the proper factor used above. Next this ignores the fact that most of the atmosphere is also at low elevation... at the top of Mount Everest for instance the atmospheric pressure is about 1/3 at sea level. At this low pressure and temperature the H2O is long gone! It fell out about base camp!

But the weights are: W(O2)=0.8387586, W(H2O)=0.1597635, W(CO2)=0.0014778 (4% H2O - subtropical sealevel)

Note I used a double floating point to do this calc. With single precision numbers there are 6.9 decimals of precision and I showed 7 so this is approximately the numerical precision of the floating point feild typically used in the modeling software.

Note the comparison of the 0.1597635 value to the 0.0014778 value. There are HUGE problems here.

Here is a quick and dirty sensitivity analysis on this weight.

Suppose CO2 were 300: then W(300)=0.0011986

This is a change in the 4th decimal. So we can rewrite the number as 0.001x??? Everything after the x is not relevant to calculations. Here I am analysing the CO2 effects at 300 PPM and 370 PPM is a rough pre-industrial post-industrial comparison to show where in the numbers one would expect this change to show up. It is in the 4th decimal position.

Now, water vapour. We already know it has a huge variation. It varies with temperature (dew point curves) and elevation. It varies for other reasons. Desserts are dry. But what of irrigated cropland? Irrigation pumps water into the atmosphere on a continous basis.

If we play with the water vapour fraction we see that it is 100 times larger. Then we see that we cannot realy measure it all that well. The change in CO2 used to compute global warming hypothesis shows up in the 4th decimal. What of water vapour changes? Are there water vapour changes? If so - how big and where would that change show up.

It is immediately apparent that the water vapour factor since it starts out 100 times greater introduces an uncertainty which is in the order of 100 times greater than the 4th decimal point and thus 100 times greater than the total ef

"It would be really nice if you started to check your facts! H2O is a more effective absorber than CO2 is. It is found at concentrations many many times CO2. H2O will be anywhere from 0% to over 4%. That is up to 40,000 PPM compared to 370. "

H20 is already at saturation .. IR wise.. adding more h20 will have minimal effect on GHG effect.
I.E. It's already blocking IR at Figure 2.. wavelengths. beyond certain thresholds adding a few thousand more ppm will have minimal net effect.. (It's a diminishing effect.)