Water Vapor Rules the Greenhouse System - Humans cause 0.28% of the "Greenhouse Effect"

geocraft.com ^ | 2003 | Monte Hieb

[TChad]

Those interested in global warming should have a look at the documentary "The Great Global Warming Swindle," produced by the UK's Channel 4. It brings together some of the world's most prominent global warming skeptics and gives them a chance to present their very convincing case. The video is about 75 minutes long.

Here is one link to the video, on Little Green Footballs:

http://littlegreenfootballs.com/weblog/?entry=24760_The_Great_Global_Warming_Swindle&

Here is a link to the Channel 4 website that describes the documentary.

http://www.channel4.com/science/microsites/G/great_global_warming_swindle/index.html

I can't help but wonder if one of the experts in this documentary moonlights as ancient_geezer.

[TChad]

Have you seen the documentary I linked in #61? It would be interesting to read your response to it.

[ancient_geezer]

Being broadband impoverished and limited to rural phoneline data speeds I haven't seen it :O(

[ancient_geezer]

I can't help but wonder if one of the experts in this documentary moonlights as ancient_geezer.

P.S. I did stay over in a Holiday Inn once ;O)

[palmer]

I agree that the model doesn't have any serious predictive value. That's beside the point because the title of this thread makes a claim about the human component to GH warming (0.28%) that is based on current conditions, not predictions. That claim is based on a 5% attribution to CO2 and some assumptions about the 30% increase in CO2 over the 20th century. I am not using Ram's model for my conclusion that a good chunk of that 30% is from fossil fuels. There's plenty of evidence for that: 13C/12C ratios, 14C ratio (before 1950's nuclear tests), and the lag from northern to southern hemisphere. There's also evidence that the 13C/12C ratio decrease is partly natural. But the bottom line is that the human contribution to GH warming is more than 0.28%, probably closer to 2% (1/2 of 30% of 12% of the total).

[ancient_geezer]

But the bottom line is that the human contribution to GH warming is more than 0.28%, probably closer to 2% (1/2 of 30% of 12% of the total).

I notice you still do not understand that the total CO2 contribution is less than 9% in the real world, per Barrett and line by line intergration of the most current HITRAN spectroscopic database, not the 12% cited in error in Wikipedia from a 1978 source paper evaluating a very simplistic model that even states 9% as the contribution of CO2.

More importantly even the 9% figure is off considerably when one recognises that neither of the above take the water vapor continuum absorption into account which actually leads to a value close to a 3% total contribution inferred by Kiehl, J. T. and V. Ramanathan, 1982: Radiative Heating Due to Increased CO2: The Role of H2O Continuum Absorption in the 12-18 mm Region . J. Atmos. Sci., 39: 2923-2926, which puts the CO2 downward radiative force at the surface at <0.55 w/m² (adjusting for the more accurate forcing estimation of Myhre et al. 1998)

Table 1. The effect of CO2 increase on the hemispherically
averaged net radiative heating (wm^-2). DF_T^N is the change
in the net outgoing longwave flux (at the tropopause) due to
doubling of CO2; negative values of this quantity denote
heating of the joint surface/troposphere system. DF¯_s is the
is the change in the downward longwave flux at the surface.

Case	Comments	-DFTN	DF¯s
1	Without H2O absorption in 12-18 mm region	4.69	3.65
2	H2O line absorption	4.18	1.56
3	Line plus continuum absorption	3.99	0.55

 

All said and done, the total contribution of CO2 works out as something substantially less than 3% of radiative forcing in the real world especially when taking clouds and precipitation cycle into account, not the erroneous 12% figure you are citing, coming from who knows where. Get a clue not even the climatescience.org folks stick by the 12% anymore, using Hansen's GCM to show a value supporting a 9% number corresponding to Case 2 above as implemented in most models included in the IPCC evaluation suite for the upcoming release of IPCC SAR4.

[ancient_geezer]

2% (1/2 of 30% of 12% of the total).

Mankind's contribution total CO2 is closer to 5% taking into account the natural CO2 emitted into the atmosphere is on the order of 160 gigatons carbon as opposed to mankind's 8 gigaton annual carbon production from CO2.

Global Sources of Greenhouse Gases
http://www.eia.doe.gov/oiaf/1605/87-92rpt/chap1.html

Most greenhouse gases have substantial natural sources in addition to human- made sources, and there are powerful natural mechanisms for removing them from the atmosphere. However, the continuing growth in atmospheric concentrations establishes that for each of the major greenhouse gases, more gas is being emitted than is being absorbed each year: that is, the natural absorption mechanisms are lagging behind. Table 2 illustrates the relationship between anthropogenic and natural emissions and absorption of the principal greenhouse gases.

 

 

Thus, in aggregate, there is 168Gt CO2 added annually. 100*8/168 = 4.8% maximum accumulating asymptotically from anthropogenic sources as we start from a resident CO2 concentration of 285ppm with nil input from mankind.

By the way, the turnover rate of CO2 in the atmosphere is about 4 years, being absorbed & re-emitted predominately through the upper layers of the ocean's biosphere, dissolved CO2 in cold ocean waters as well as absorption through photosynthesis and ultimate bio release back into the atmosphere as plant tissues are metabolized and biological CO2 returned to the environment from the food chain.

[avg_freeper]

Blinking stars in

CGEB's profile page

and blinking stars in

brityank's profile page

Same state too, interesting ...

[TChad]

Being broadband impoverished and limited to rural phoneline data speeds I haven't seen it :O(

:O( is right. Damn. The documentary is intended for public consumption, but in my opinion the scientists interviewed make a very compelling case. It would be great to read your expert review.

Just FYI for you or for lurkers, the video on Little Green Footballs can be downloaded as a 218 MB flv file using the free DownloadHelper add-on to Firefox, and played with this free flv player. So, you could ask someone you know who has broadband to download the program and burn it to a CD for you. Then you just install the flv player and watch the program.

You might be able to download the program yourself using dialup, but it would take hours, and download failure would be likely.