Talk:Greenhouse effect

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Real Greenhouses and Real Atmospheres[edit]

Convection and conduction can only transfer heat from a hotter place to a colder one, so by definition, since a greenhouse is hotter on the inside than it is on the outside, heat will always flow from the inside to the outside, cooling it off instead of heating it up -- the exact opposite of what the greenhouse effect is supposed to do.

In other words, it is physically impossible for real greenhouses warm up due to convection or conduction, they can only warm up due to radiation ("by allowing sunlight to warm surfaces"). Warming up is the greenhouse effect; cooling down is not.

So whether it is a real greenhouse or a real atmosphere, the only way for energy to get into either one of them is via radiation, therefore the ONLY role convection or conduction can ever play in the greenhouse effect or in real greenhouses, is by counteracting the greenhouse effect by cooling them off.

This is all elementary thermodynamics and explains why radiation is considered the primary factor for creating a greenhouse effect (the warming effect), and not the other way around, i.e. -- by limiting convection or conduction (limiting the cooling effect).

Case in point, Standford engineers invented a coating to help cool buildings, and the way in which this coating worked was presented in a peer reviewed science journal using a miniature real greenhouse, i.e. -- a "rooftop apparatus" in which convection and conduction were minimized using polystyrene and an enclosed container. This setup was very much like the Wood's Experiment, only the Stanford experiment was properly conducted under rigorous scientific conditions and clearly eliminated any unknown variables that the Wood's experiment did not. The thing to note about this peer reviewed scientific experiment is that without any convection or conduction, THE TEMPERATURE NOT ONLY DID NOT RISE, IT EVEN COOLED TEN DEGREES BELOW AMBIENT. This proves that limiting convection does cannot create or cause the greenhouse effect, but that convection is just merely undesirable effect, detrimental to the greenhouse effect, with RADIATION BEING THE PRIMARY CAUSE OF THE GREENHOUSE EFFECT, both in real greenhouses and in the real atmospheres.

Just like a perfectly built real greenhouse, the real Earth cannot gain or lose heat by convection or conduction, it can only gain or lose heat by radiation. An imperfectly or improperly built real greenhouse can lose excessive heat by way convection or conduction, but that only counteracts the greenhouse effect, it does not contribute to it in any way, shape, or form.

References:

[1] Heat Transfer. Wikipedia. https://en.wikipedia.org/wiki/Heat_transfer

[2] Second Law of Thermodynamics. "Heat always flows spontaneously from hotter to colder bodies, and never the reverse, unless external work is performed on the system". Wikipedia, https://en.wikipedia.org/wiki/Second_law_of_thermodynamics

[3] Aswath Raman et al (2014). Passive radiative cooling below ambient air temperature under direct sunlight. NATURE, VOL 515, 27 NOV 2014, http://www.nature.com/nature/journal/v515/n7528/full/nature13883.html

Recent changes[edit]

Incivility collapsed

I cannot believe I have to justify my deeds to a vandal, but the fact is, i have to.

The source (IPCC) says "greenhouse gases trap heat within the surface-troposphere system. This is called the greenhouse effect." and "thermal radiation emitted by the land and ocean is absorbed by the atmosphere, including clouds, and reradiated back to Earth. This is called the greenhouse effect" (which is just another way to say exactly the same: greenhouse effect is about the loop between thermal radiation from the surface and part of it that atmosphere send back after having absorbed it. Note that greenhouse effect is NOT about the whole radiation from atmosphere to surface; even without greenhouse effect, atmosphere gets some energy by many other process and radiates part of it back to surface

The previous version of the article said "the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without its atmosphere.", which is wrong and wrong and wrong

  • wrong because the whole radiation from a planet's atmosphere do not belong to greenhouse effect
  • wrong because the atmosphere, being colder that surface, cannot warm it
  • wrong because nowhere in the source you'll find such nonsense, you just cannot attribute the wrong statement to a source that do not endorse it (for a reason: it is physically absurd)

I corrected it, also adding some matters like optical depth, and substracting irrelevant details that belongs to greenhouse gas, not greenhouse effect (unless we merge thess articles, which i don't promote). User:William_M._Connolley reverted, which is rude, with a rude comment, and no explanation. Well, good faith assumption, and everybody can make mistakes and stubbornly stick to them. I corrected again, and talked on his page.

And he again reverted, again without explanation (i don't count "better before, I think" as an explanation, neither is the comment he made in reply on his talk page), which is just a conflict building in violation of WP rules.

Warning: we are past the vandalism point. Gem fr (talk) 10:30, 21 June 2017 (UTC) disclaimer: i am confident you can make it even better (even the vandal, provided he first learns to behave, to attributes to sources what they indeeed say, etc.). Provided you don't just revert, and do some actual work. Gem fr (talk) 10:30, 21 June 2017 (UTC)

William M. Connolley passed by, and just collapsed a so-called incivility (well, that's ok for me).
since he did had some activity meanwhile, i guess he just has nothing to answer to me.
Does anyone object to us moving on, that is, to restore the article in my last form (from which it can then be edited again, as per my last previous comment)? Gem fr (talk) 09:04, 22 June 2017 (UTC)
You write an awful lot to show umbrage at a mild description of 'silly' and start throwing around accusations of vandalism and describing silly as equivalent of swearing does you no credit. Would it be any wonder if people concluded you were writing lots of edits to an article that has evolved through lots of different editors reaching consensus and one editors version was not an improvement. Having said this, perhaps if the discussion turned to whether optical depth needed to be introduced so early and it was agreed that it should then maybe there could be some improvement to the article. Personally I doubt it needs to be introduced so early. So generally I think better as it is than with all of your edits. crandles (talk) 10:10, 22 June 2017 (UTC)
Excuse me to take umbrage of seeing the article reverted to a version containing plainly wrong sillyness, with no explanation, accused of playing silly game, not answered when i ask why, etc. I guess you are so wise you wouldn't had failed to the fault. Following the group and preventing its disbanding is so much more important that to fix the content to make it encyclopedic, we should really frown upon the guys that begins shouting "EH, GUYS, there is someone doing it wrong" when ignored (irony/sarcasm inside, no pun intended).
I don't care for credit, and you shouldn't either. All what we do is under CC, made under pseudonym, and I easily remember very good contribution from otherwise very despicable, bad mannered and bad tempered people.
There is so much "consensus" that the article is semi-protected, subject to special discretionary sanctions, and its history shows countless editorial revert (not just restoration after childish vandalism) and edit war; already staring William M. Connolley, btw, i now observe: this guy should had be policed long ago, but, whatever, who knows, he may have some qualities that make up, pretty much the way rose flowers protect their prickles (he didn't showed them to me, still)...
and, there may be "lots of different editors", but the fact is, the last of them put the article from a state (with no less consensus, AFAIK) where it accurately reproduce the definition of source IPCC, to current state where the source has been conserved but the definition altered in a nonsensical way. Well, good faith for sure, but, what the heck? Good faith is not trustworthiness, but i guess "lots of different editors" just didn't notice, or they would had protested, since they had left the article in a correct state.
Whatever the cause (eg: good faith assumption, so you don't think that some editor twisted the definition to something very different (and wrong) from conserved source), your argumentum ad populum proves to be bandwagoning).
and I checked very few things, so, excuse me to assume that "lots of different editors" did the same as i did (that is: didn't check anymore than i did; I am no better than they are and they are no better than i am), meaning any number of reference may tell things different or even opposed to what the article make them endorse. Chilling.
On the other hand, a few browsing the archive section shows that very sound material, agreed by everyone, somehow didn't made into into the article while needed, or even were derailed (as the definition was).
optical depth was just not mentioned, i added it, and you seem to agree it had to be done. I don't object if you think i did too early (it indeed is quite technical)
Bottom line: try again, none of your argument to "think better as it is than with all of [my] edits" stand.
But then again, this is not a matter of "as it is" Vs "with all my edits". You, as any other, are free to make it better, started from whatever version suits you more. If you don't, you just make us lose our time.
Gem fr (talk) 14:36, 22 June 2017 (UTC)
Elsewhere you asked me for advice and I replied "make effective use of WP:Dispute resolution". This lengthy post is not that. NewsAndEventsGuy (talk) 16:05, 22 June 2017 (UTC)
This post may be full of flaws, but it does exist. It maybe not be "effective", but it manifests my "use of WP:Dispute resolution". Obviously the other party don't even try, does it? Gem fr (talk) 10:34, 23 June 2017 (UTC)

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NPOV violation[edit]

This article claims that "heating in the usual greenhouse is due to the reduction of convection,[32] while the greenhouse effect works by preventing absorbed heat from leaving the structure through radiative transfer." I submit that this is a violation of NPOV.

The theory that insolation entering a container via glass heats the interior by trapping thermal radiation was first demonstrated experimentally in 1767 by Horace de Saussure. The portion of the IPCC report cited as reference [14] in the present article bears this out as follows.

"The ability to generate an artificial warming of the Earth’s surface was demonstrated in simple greenhouse experiments such as Horace Benedict de Saussure’s experiments in the 1760s using a ‘heliothermometer’ (panes of glass covering a thermometer in a darkened box) to provide an early analogy to the greenhouse effect."

Although this was the first such scientific experiment, de Saussure himself motivated it as follows. "it is a known fact, and a fact that has probably been known for a long time, that a room, a carriage, or any other place is hotter when the rays of the sun pass through glass." This directly contradicts the present article.

Quoting the same source, "De Saussure first built a miniature greenhouse five walls thick. He constructed it from five square boxes of glass, decreasing in size from 12 in. on a side by 6 in. high to 4 in. on a side by 2 in. high. The bases of the boxes were cut out so the five boxes could be stacked one inside the other atop a black wooden table. After exposing the apparatus to the Sun for several hours, and rotating the model so that solar rays always struck the glass covers of the boxes perpendicularly, de Saussure measured the temperature inside. The outermost box was the coolest, and the temperature increased in each succeeding smaller box. The bottom of the innermost box registered the highest temperature—189.5 °F." (87.5 °C).

[It should be clear that if the glass covers were only preventing convection then the five interiors of the boxes would equilibrate to the same temperature as one box with one pane of glass, as additional panes cannot further decrease convection.]

The next such experiment was conducted more than 120 years later, described as follows by Charles Greely Abbot in an article published in July 1909.

"On November 4, 1897, the thermometer recorded 118°C within a circular wooden box 50 centimetres in diameter, 10 centimetres deep, insulated in feathers, covered with three superposed and separated sheets of plate glass and exposed normally to the sun rays in the yard of the Astrophysical Observatory at Washington. The temperature outside was 16°C."

Abbot's article rebuts the experiment that the present article cites as reference [6], namely a one-and-a-half-page article published in February 1909 about an experiment with two boxes with respectively glass and salt lids which both reached an interior temperature of about 60 °C, almost 60 degrees cooler than the experiment conducted at the Smithsonian Astrophysical Observatory a decade earlier. [Since a salt window traps no thermal radiation there is no way a box with three salt windows could reach 118°C (244 °F) purely by blocking convection.] This six-paragraph article contains not a single calculation, nor a single reference to or acknowledgment of any prior experiments supporting the opposing theory, and concludes, surely redundantly, "I do not pretend to have gone very deeply into the matter".

The next occasion on which this matter came up for debate was in the 1970s as reported a decade later by Professor Craig Bohren, who pointed out that ""the atmospheric science community seems to be divided into two groups". Bohren does not takes sides on the question, and it is pretty clear from his discussion of the two groups that Wikipedia is in violation of NPOV when it dogmatically takes one side on the question with no mention whatsoever of the extensive support for the other side since 1767.

Wikipedia has stacked the deck here by citing a single almost completely undocumented experiment while refusing to cite far more professionally documented experiments supporting the other side, even after I pointed them out to the owners of this article back in 2010. Instead they simply deleted my edits. To strengthen their case the editors added the following bit of OR. "Outside, the warm air near the surface rises and mixes with cooler air aloft, keeping the temperature lower than inside, where the air continues to heat up because it is confined within the greenhouse. This can be demonstrated by opening a small window near the roof of a greenhouse: the temperature will drop considerably." Their response to my request for a citation for their theory and gedankenexperiment was simply to delete my request. Vaughan Pratt (talk) 01:06, 27 December 2017 (UTC)