Part 1 - Do you really understand the "greenhouse effect"?

Question

This is the first part of a two part question. Part 1 will look at the basics of what is commonly known as the "greenhouse effect". It is my belief that there are many misconceptions surrounding this term.

Most people are probably aware of a real greenhouse having been in one and noticing they are much warmer than the outside air. And most people are probably aware of the term "greenhouse gasses" such as CO2 and the "greenhouse effect" related to climate change.

Let's go back to a grower's greenhouse. On a nice sunny day, the inside of a greenhouse warms up compared to the outside temperature. But does this occur due to the greenhouse gasses like CO2 and water vapor inside the greenhouse? No, it doesn't.

"...the warming effect in a real greenhouse is not due to long wave infrared radiation trapped inside the building, but to the blockage of convective heat transfer with the surroundings..."
http://www.biocab.org/Wood_Experiment_Repeated.html

One can clearly surmise that the Earth's atmosphere has no glass wall (i.e. physical barrier) which prevents convective heat transfer and thus is nothing like a growers greenhouse.

So how did the Earth's atmosphere come to have such an incorrect description of it? Do most people understand this?

Answer 1

The term ‘greenhouse effect’ is just one of the thousands of technically inaccurate terms that are used in any modern lexicon. If we didn’t use them then language would become sterile and convoluted.



We talk about the world being round, but it’s not, it’s an oblate spheroid. If someone has a lateral epicondylitis we’re more likely to say they’ve got tennis elbow, even though it’s got nothing to do with tennis. And you know that digital camera you’ve got, it’s not a camera.



The fact that it’s described as an EFFECT implies that it’s not simulating or replicating a greenhouse but that the produced consequence is the same, which essentially it is.



The whole concept of language is that it allows us to communicate and as long as the parties to the communication understand what is being said then it’s irrelevant what terminology is used.



In the vast majority of cases we don’t need to know how something works in order to know what it is. You’re now reading something I wrote earlier and several thousand miles away but do you know how that has been made possible. It’s irrelevant, whether you know or not the outcome is exactly the same.



As an example of the fact that the terminology is irrelevant, consider that in other languages it’s not called the Greenhouse Effect. The Germans call it the Blowing House Effect, the Greeks refer to it as the Emissions Phenomenon and in some African dialects it’s simply The Warming.

Answer 2

This is a very interesting read. As I understand it this paper raises two major issues with ‘the standard model’. 1. The standard model might be fine for representing astronomically distant objects, but it assumes that the object is a flat disk, and that the derived surface temperature is constant across the surface of the disc. This is not a valid model for the earth. 2. The standard model does not consider the dark side of the earth where the radiative conditions (and therefore the corresponding surface temperatures) are quite different. I’m not aware of how the radiative balance is ACTUALLY represented in the GCM’s, so don’t know if, or to what extent these two factors are considered. But I would be very interested in reading any responses on the substance of this document. Has anyone see a response to the substance of this paper from anyone in the climate science community?... anything from Trenberth on this?

Answer 3

This has been covered in here numerous times. Some books call it by the name "atmosphere effect" instead. People use lots of incorrect terminology and think of things in terms of mental pictures that are not correct. People also say that the atmosphere acts like a blanket--no it doesn't, but at a certainly level of simplification that is useful. While Wood's experiment seemed to show that the primary contribution to keeping the greenhouse warm was suppressed convection, I'm sure more accurate measurements would have shown that the greenhouse effect contributes also. Didn't d/dx +... state this recently?



More than once in this forum 'skeptics' have thought that they were making some great revelation about AGW by pointing out that the terminology is misleading. It is essentially irrelevant to the validity of AGW.

Answer 4

Yes, this a common misconception and one that is perpetuated by continually using the term.



However, lacking a better description, one that is easily digested by the public as a whole, it will continue to be used. That's the crux of the problem. For broad public understanding, complex subjects usually have to be distilled down, sometime beyond what can be considered accurate.



Oddly, I even remember seeing someone describe warming in an actual greenhouse the way CO2 and other GHGs trap heat (absorbing long wave radiation).

Answer 5

Sometimes names are oversimplified and actually end up causing confusion. The terms "global warming" and "climate change" are good examples. I don't think any decent scientist would use those terms because they imply that the earth's climate was stable until humans came around. They are useful terms for alarmists who attempt to fool the gullible and ignorant.



I think virtual is overthinking the question. It isn't dialectic. It is simply asking if the name is worthwhile. I don't think you are arguing that there is no greenhouse effect. I don't think Virtual thinks that. I think he is just trying to use a dialectic argument by bringing up dialectic arguments. It is a major tactic of alarmists to distract from facts.



Note: Interesting points Trevor. I kind of liked the German blowing house effect (not really sure what that is) or the more precisely worded Greek emissions phenomena. I think that often the science gets lost in the definition. For example, in spite of claims to the contrary, the definition of GW isn't always just AGW. If we could all agree on the meanings of the names, it wouldn't be less of a problem to use simplified names. The problem is we don't always agree. Sometimes the name means one thing and another time it means something else.

Answer 6

Part I is attempting to parse the "debate" about global warming as a semantics problem. This is dialectic argument - a favorite of marxists, jesuits, and others that do not want real world facts to interfere with their ideology. Phrased as "teach the controversy" it is also a major tactic of christian fundamentalists. It is a debating tactic for winning arguments, not scientific inquiry.

Answer 7

yes i understand the whole process because i took a class