Any other comments?

Also disproved by CERES TOA measurement which shows no increasing trend in the difference between outgoing and incoming radiation and therefore no missing heat during the current GAT standstill despite increasing CO2 during that same period.

Any other comments?

I'm sure I'm missing lots of detail but to me the CO2 theory, though vaguely plausible, falls apart at a very basic level so I don't understand why it is quite so excepted by most people as a given and then extrapolated to ridiculous extremes.

I do understand that CO2 absorbs IR, but I think it is a big leap to go from that to heating the atmosphere.

I can't say for certain, but I remember as a lad reading that the temperature on Venus was caused by "greenhouse gases" and CO2 was the major cause - I believe a young Carl Sagan was responsible for this theory. It is now thought that it was evaporation of the water on the planet that caused the runaway warming, although I'm not sure how the planet got to 96.5% CO2. Venus also has an atmospheric pressure of 93 bar, and revolves towards the west - the only planet in the solar system to do so. The theory is just that, a theory, and while I expect we'd probably get the runaway greenhouse effect at 965000 ppm CO2 we're probably reasonable safe at 400 ppm of CO2. There's quite a bit to think about, if the pressure is that high due to a dense atmosphere then the temperature would rise because of the ideal gas law assuming the volume remained the same. Or it could be that the pressure went up because if the temperature. I don't believe anyone knows for sure.

"What do we see in real life."

The Bolivian Altiplano gets mighty nippy at night +20 -> -20 is a pretty standard change at some points of the year. A slight shame it gets so cold as it puts you off slightly admiring that absolutely stunning star dominated night sky.

I've not seen any evidence of climate researchers doing experiments for things like this or as you say rhoda even publishing what the expected outcome should be.

May 17, 2014 at 7:25 PM | Registered CommenterMike Jackson

Mike, well I was a student climate scientist but unfortunately I only really got to piss around with a computer program. I did learn alot in my time there though (about computers in particular). I think one of the issues with subjects such as Meteorology is it is dominated by people with Maths backgrounds, which is all well and good, but a mathematician isn't a scientist.

MJ: "Now somebody pop up and tell me that "they" have done this."

Of course they have Mike but as 'they' were being paid to find global warming, that's what 'they' did.

Hello all,

I have been searching for years to find answers to many of the questions raised and discussed in this thread.

It warms my heart that skeptics are capable of challenging each other about theories vs facts and insisting that theory correspond to facts. If the facts are not available then we know an unknown that needs to be known.

I haven't seen any discussion on the warmest side that comes close to this dedication to finding the truth.

I congratulate you all. I am not well informed enough to make an intelligent comment on anything raised in this thread but greatly appreciate your efforts. Thank you all. I have learned a lot.

Browsing the literature on downwelling radiation there's a fair bit, mostly PDFs and book references.

There' s a graph here .

It is from Desert Meteorology by Thomas Watkins. The graph is on page 171 and the curve of downwelling longwave radiation is labeled I with a downward arrow.

Curses. How does one make <a href work?

here

Second attempt.

I haven't seen any discussion on the warmest side that comes close to this dedication to finding the truth.
...
May 17, 2014 at 8:31 PM Peter Fournier

Perhaps that's because they believe that 'the science is settled' ?

Thank you for your remarks, Peter.

"May 18, 2014 at 6:07 AM | splitpin"

The thing is I don't ever recall the science of AGW being discussed past the trivial, it absorbs IR phase - Well it must be the H2O then as there is an unlimited amount of it available. The 'climate scientists' all seem more interested in discussing the personalities and politics of it all.

May 18, 2014 at 6:54 AM | Registered CommenterMartin A

My complete guess at how the atmosphere works as that some level of GHG sets up the circulation as we know it, ie convection, moisture and latent heat transport, and importantly IR emission to space at altitude. but the amount of them doesn't make much difference (water vapour and clouds can come and go very quickly and probably control things greatly).

I'm still very interested in the long term changes in climate from years to millions of years and what might cause that to happen. For example I find it very interesting things like the implications of a snowball Earth and whether it existed ever.

Yes, Martin, I often end up at the engineering toolbox when looking for physical constants.

The specific heat capacity of dry or moist air is approximately 1 kJ per kg per degree K. [ref 1 and 2]
At tropical temperatures of approx 30 Celsius at sea level, saturated air contains approximately 3% water. [ref 3]
The latent heat of vaporisation of water is 2260 kJ per kg. [ref 4]

Thus, for example, a change of humidity that corresponded to an increase or decrease of just 1% water would take up or release sufficient heat to raise the far greater amount of dry air by roughly 23 degrees Celsius. [note/ref 5]
These energy changes dwarf those due to the heat capacity of air, and are also concentrated where the cooling occurs.

The, quite reasonable IMO, explanation I have usually seen is that when humidity is high enough diurnal temperature ranges in the tropics are dominated by water cooling evaporatively during the day (and forming clouds) and releasing heat not only by raining, but also by condensing at night (and also the insulative radiative cloud effects). It's what helps keep the equatorial rainforests at relatively constant warm surface temperatures when compared to other climates.

[1] http://www.engineeringtoolbox.com/air-properties-d_156.html
[2] http://www.engineeringtoolbox.com/specific-heat-ratio-d_608.html
[3] http://en.wikipedia.org/wiki/Water_vapor (Wikipedia is good enough here)
[4] http://en.wikipedia.org/wiki/Enthalpy_of_vaporization#Selected_values
[5] Calculations based either on mass% or volume% do not change the conclusions.

Martin A: "So greenhouse effect involving water vapour remains as the likely explanation."

They way I imagine it is that the lapse rate controls the near-surface temperature but you have to start at a point in the atmosphere and work backwards. A good point would be the radiating height of the average Stephan-Boltzmann derived average Earth temperature, -18 degC, . Dry lapse rate is around 10 degC / km in desserts and around half that in very high humidity.

Over a dessert, the S-B height varies dramatically between night and day driven by large swings in surface temperature. If it occurs 1 km above the ground then the near-surface temperature would be -8 degC. If the near-surface temperature was 42 degC then the S-B height would be 5 km.

Over tropical rainforest the temperature may vary very little around 32 degC and the S-B height would be around 10 km with little variation as extreme surface temperature swings are prevented by evaporation-condensation-precipitation.

The only thing that carbon dioxide affects is the S-B temperature height. As this occurs in the troposphere along with most of the water vapour, its effect on that is small in comparison and even smaller is the effect of additional CO2.

Thanks Michael. Am I right in saying that you don't believe that either CO2, or water vapour play a big part as GHGs and that the evaporation and condensation of water in the tropics accounts for the small diurnal range of temperature?

We have been through all of this before. See BH discussion thread "Can Trenberth do sums" from September 2013.

As far as I am concerned, empirical data (records of desert temperatures) have conclusively falsified the CAGW hypothesis - which was based on no empirical evidence at all.

Back to the day job, and no more time to participate - best to all.

Rhoda

I'm happy to accept the S-B Law as describing the correct relationship between the surface temperature of a body and the energy that it radiates. A planet is unevenly heated and cools unevenly but will have an average for both. A rocky planet with no atmosphere will radiate from its surface. Add a non-radiative atmosphere and it will continue to do the same. Add a radiative gas and it will radiate from both surface and atmosphere. The average radiating temperature will now be found at some height in that atmosphere. S-B says that for Earth the temperature is -18 degC. Is that controversial?

If we move on from there to observations of the atmosphere we see that -18 occurs at different heights. You can calculate that height locally if you know the lapse rate or conversely you can calculate the surface temperature if you know the lapse rate and the temperature at a particular height. Controversial?

The near-surface temperature average for Earth is ~ 14 degC. If that 32 degC above S-B can be explained by lapse rate then that is the greenhouse effect. And if so, the correct definition is a planet with a greenhouse effect has its S-B temperature located at some average height above its surface and a planet with no greenhouse effect has its S-B temperature located at its surface.

I could be wrong but current greenhouse theory doesn't convince me that I am.