Talk:Idealized greenhouse model

Original research?

Is this a generally accepted (or at least acknowledged) model? The article is completely unreferenced, and I get zero Google Scholar hits for "Idealized greenhouse model". In its current form, it probably violates WP:OR. Hqb (talk) 18:23, 13 December 2008 (UTC)

It is common in many textbooks. I will try to find an online reference. Incredio (talk) 18:27, 13 December 2008 (UTC)

References now added. Incredio (talk) 18:45, 13 December 2008 (UTC)

OK, but please include proper title and author information for the anonymous PDF file used as a reference, otherwise it's useless. Hqb (talk) 18:54, 13 December 2008 (UTC)

This looks like std stuff. Its not OR (well I only skimmed it so I'm assuming its been done properly) William M. Connolley (talk) 20:02, 13 December 2008 (UTC)

Yeah, I didn't spot anything cranky in the physics; I was mainly concerned about whether the model as presented is generally considered a good approximation of climatological reality (i.e., accounts for most major factors), or whether we were getting into spherical cow territory. Without verifiable references it's hard to tell. Hqb (talk) 20:47, 13 December 2008 (UTC)

Its not a particularly good representation of reality, at least in the naive version where you interpret one layer as the surface and the other as the atmosphere, but the page correctly notes that you can interpret one layer as the lower and the other as the upper atmosphere (a little appreciated fact, so bonus points there). Its a standard pedagogical construction - I'm surprised it isn't elsewhere on wiki. Its certainly in the talk pages William M. Connolley (talk) 22:15, 13 December 2008 (UTC)

I think that there is a problem with the physics of the atmosphere. The atmosphere can not radiate with 2σTa^4 that should be only σTa^4 of which half radiates to the ground and the other half to space. —Preceding unsigned comment added by Oin34 (talk • contribs) 12:50, 12 August 2009 (UTC)

No, it is correct as written in the article. One looks at the energy budget in each direction. For each direction there is F=σTa^4. the article is in total agreement with this speech from David Archer, called The Greenhouse Effect. --Hg6996 (talk) 09:09, 22 May 2013 (UTC)

Question about albedo

I'm a little confused. The article says that the albedo is 0.30, but the drawing says 0.60. Am I missing something? Q Science (talk) 19:07, 14 December 2008 (UTC)

Thanks for pointing that out. I clarified the caption. But that is a good idea to draft figures to represent exactly the solutions for Earth, with and without the greenhouse effect, as discussed in the text. I will do that by 2009. Incredio (talk) 02:30, 15 December 2008 (UTC)

Figures now changed to represent solutions in text. Incredio (talk) 17:22, 15 December 2008 (UTC)

Non-greyness ?

I wonder if the last sentence is correct:"This is directly related to the non-greyness of the real atmosphere." From what I know, the reason why temperature in the stratosphere is higher than in the upper troposphere is because of the non-transparency, which means "greyness", not due to the non-greyness!? Am I wrong ? --Hg6996 (talk) 09:24, 22 May 2013 (UTC)

"grey" means that the transmissivity is the same across all wavelengths William M. Connolley (talk) 10:43, 22 May 2013 (UTC)

Thx a lot, now I got it! I simply wrongly translated the word "greyness". With your help I was able to correct my fault. :-) --Hg6996 (talk) 16:27, 24 May 2013 (UTC)

Excellent article. I had the same misunderstanding on first reading. Could we add clarification by extending that last sentence: "This is directly related to the non-greyness of the real atmosphere, which absorbs more at the short end of the spectrum." Dave (talk) 12:07, 13 March 2017 (UTC)

Question about radiative forcing ?

You state: "The radiative forcing for doubling carbon dioxide is 3.71 W m−2" What is the source for this figure? The references you give do not link to anything that can be deemed to be the source. What I fail to understand it how adding carbon dioxide can materially increase global warming once all the radiation within the wave lengths that it can absorb has been absorbed? I want to see how the figure is calculated and need to see the source. Paidion777 (talk) 12:34, 8 September 2015 (UTC)

You can find the 3.7-forcing-value for example here on page 38. --Hg6996 (talk) 12:48, 25 September 2015 (UTC)

(i.e., the earth is a black body in the infrared, which is realistic)

A better formulation is: "(The Earth is nearly a black body in the infrared.)"

A realistic value is 0.95.Hensch56 (talk) 14:45, 4 October 2021 (UTC)

Flat Earth,

The diagrams showing up/down radiation have the Earth as horizontal. Isn't a correction needed for Earth's curvature? Damorbel (talk) 20:20, 14 September 2022 (UTC)