If the anthropogenic global warming theory is wrong, why is the upper atmosphere cooling?

Question

The anthropogenic global warming (AGW) theory predicts that the lower atmosphere and surface should warm due to greenhouse gases trapping heat, while the upper atmosphere should cool.

One way to think about this is that the amount of infrared heat energy radiated out to space by a planet is roughly equal to the amount of solar energy it receives from the sun. If the surface atmosphere warms, there must be compensating cooling elsewhere in the atmosphere in order to keep the amount of heat given off by the planet the same

http://www.wund.com/education/strato_cooling.asp

If the Sun were responsible for global warming, any increase in solar radiation would heat the entire atmosphere.

So what's actually happening?

"cooling trends are exactly as predicted by increasing greenhouse gas trends"

http://www.realclimate.org/index.php/archives/2006/11/the-sky-is-falling/s=ionosphere+cooling&qt=&q=&cx=009744842749537478185%3Ahwbuiarvsbo&cl

Can skeptics explain this discrepancy?

Trying again on the second link:

http://www.realclimate.org/index.php/archives/2006/11/the-sky-is-falling/

Tomcat - as you point out, the stratosphere is tricky because of interactions involving ozone. However, the mesosphere and ionosphere have also been cooling (though I can't find a good graph showing this - if someone can locate one, a link would be appreciated).

This is strong evidence for AGW and against solar warming.

Jim - the AGW theory predicts that the upper atmosphere will cool as explained in the quote and link above. If you don't 'buy' (a.k.a. understand) the explanation, that's not my problem.

My challenge to skeptics is to explain why the upper atmosphere is cooling (and the lower warming) if the AGW theory is wrong, because the entire atmosphere should be warming if the Sun is responsible.

J S - the Singer was (I think) entirely about the troposphere not warming as much as the theory suggests. The AGW theory says the troposphere should warm more than the surface, and it appears not to be (they seem to be warming at approximately the same rate).

It's unclear whether this is due to problems with the satellite measurements, theory, or a combination. However, their conclusion that this discrepancy suggests that the planet is warming due to natural causes discounts the upper atmosphere cooling and surface and cryosphere warming as the AGW model predicts.

They're basically saying "there's one inconsistency, therefore this theory is wrong even though the alternative we propose has many more inconsistencies".

By the way, the upper atmosphere cooling due to the greenhouse effect is illustrated perfectly on Venus.

The surface of Venus is extremely hot because most of the atmosphere is CO2. However, the upper atmosphere is much colder than the Earth's upper atmosphere. It's all discussed in the first link above.

You can also read the details about this upper atmosphere cooling effect at these links:

http://www.atmosphere.mpg.de/enid/20c.html
http://www.realclimate.org/index.php?p=58

Greenhouse gases absorb infrared radiation from the surface of the Earth and trap the heat in the troposphere. If this absorption is really strong, the greenhouse gas blocks most of the outgoing infra-red radiation close to the Earth's surface. This means that only a small amount of outgoing infra-red radiation reaches carbon dioxide in the upper troposphere and the lower stratosphere.

On the other hand, carbon dioxide emits heat radiation, which is lost from the stratosphere into space. In the stratosphere, this emission of heat becomes larger than the energy received from below by absorption and, as a result, there is a net energy loss from the stratosphere and a resulting cooling.

Answer 1

Do you mean the upper layers of the atmosphere?

The Troposphere is the only layer showing warming trends. The mesosphere and thermosphere (ionosphere and exosphere) are showing cooling trends. And a logical explanation for that would be the CO2 and other greenhouse gasses trapping more heat in the troposphere when it should be radiating up to the upper layers of the atmosphere.

So yes i think that greenhouse gasses are causing this unusually trend in falling temperatures in the other atmospheric layers. (excluding the troposphere)

I can't really think of any other logical reasons for the upper layers to be cooling because "global warming skeptics" think its all a "cycle" and the sun is to blame. So if the sun is to blame for this change, then wouldn't ALL of the layers be warming and not just the troposphere. Funny relationship eh?

Answer 2

"the amount of infrared heat energy radiated out to space by a planet is roughly equal to the amount of solar energy"

Yes, it's hard to follow but if I think of the atmosphere purely as a sort of "radiation resistor", heat caught somewhere has to be offset by less heat caught elsewhere, so it's plausible that makes sense speaking of radiation only, with a slight deficit on the escaping radiation going towards warming.

When talking about details within the actual atmosphere though I'd want to know more. Is radiation the primary mechanism for warming the atmosphere (at all levels), or could convection warm the atmosphere as well while radiation still has its baseline effects? Would higher temperatures lead to more active diffusion and therefore more conduction (including between atmospheric layers)? Could more active convection carry heat farther up/out, irrespective of the radiation flows? How much heat does the atmosphere itself radiate?

I'm not questioning whether or not scientists have answered these questions to their own satisfaction, I'm just curious for a peek into their science and wondering if it's all figured out or if some of it may be open topics of research, hence the Singer, Christy et al paper. Singer's potential bias concerns me, but I'm curious to know if they're even fishing in a pond that has any fish left to pursue.

I'll have to follow some of the links from that first page to get more on radiative transfer theory.

From the answers here it's obvious that people replied without following the link! I'll label it clearly so they can seek clues.

Answer 3

I think it's as close to zero as you can get that the theory about greenhouse gases warm the earth is wrong. I do think however that there might be about a 25% chance that the consequences won't be as bad as IPCC predicts. There might also be at least 25% risk that the consequenses might be more severe than what they think. Whatever will happen I'm quite sure that our current way of dumping emissions of greenhouse gases into our atmosphere eventually WILL cause the world a lot of trouble and that we better turn towards more sustainable ways now instead of getting ourselves further onto the wrong road.

Answer 4

One problem with your statement is that the atmosphere with the exception of H2O (Short Wavelength IR) and O3 interacting with UV is basically invisible to incoming sunlight. And secondly stratospheric temperatures have been flat for ten years. Any CO2 based warming observed over the last ten years should show up as cooling in the stratosphere. You can say that no other theory can explain it beside AGW, but you cannot back it up with data. Unless you want to go out on a limb and speculate that ozone recovery in the stratosphere is counteracting the cooling that should be observed.

http://wattsupwiththat.wordpress.com/2007/11/26/the-scoop-on-satellite-temperature-data/

http://en.wikipedia.org/wiki/Solar_radiation


Oh, and your second link did not work.

Answer 5

So let's get this straight. You are suggesting that increasing the concentration of CO2 in the atmosphere will cool the stratosphere because it is warming the surface and you want skeptics to explain it. Sorry, it just doesn' the ring of truth to it IMO. You are just glossing over the fact that increasing CO2 in the upper atmosphere is causing cooling. I know you are suggesting that it has to be cooler in the upper astmosphere to counter the warming of the troposphere, but that doesn't explain why greenhouse gases don't work to hold the heat at higher altitude. If CO2 is warming the lower the atmosphere it should warm the upper as well. It seems like common sense to me. If the lower atmosphere gets warmer, heat will radiate upwards. There is no mechanism which I am aware of to account for this just so that the heat radiating into space remains the same.

Answer 6

ok 1st of all, there is no increase in solar radiation. Also, the Earth is not giving off more heat, the theory is just that the earth's atmosphere is trapping more of what the earth does give off, though I don't nessesarillay believe it it human caused though

Answer 7

Global Warming is part of life and so is Global Cooling. It just has to do with the cycle of the sun and it's relationship to the planets.

When the sun goes Nova we will go into a cooling period again. Check out the information on year 2036 for solar flairs and cooling and pole reversal.

Answer 8

well if we could make the cold countries warmer without affecting anybody it would be cool

Answer 9

Of course they can answer it, as long as there are ignorant people out there believing them. Just count yourself lucky you are not one of them.