NOAA's climate.gov PR effort is designed to deceive us, but it would be nice if they would at least try to do so by twisting the truth, rather than tell outright porkies. On the page https://www.climate.gov/news-features/understanding-climate/global-warming-frequently-asked-questions under "What is the 'greenhouse effect'?" we find this audacious display of dishonesty:
While it's not a perfect analogy, some say the atmosphere works like a greenhouse. The sun's rays (shortwave energy) enter a greenhouse through its glass ceiling and walls to warm the interior. The glass makes it hard for the heat (longwave energy) to escape, and heat builds up inside the greenhouse until the heat can escape fast enough.
Certain naturally occurring gases in Earth's atmosphere have a similar warming effect on the surface. This warming is referred to as the "greenhouse effect," and the gases that trap heat are called "greenhouse gases." The most important greenhouse gases in Earth's atmosphere are water vapor, carbon dioxide, methane, and ozone. Earth's surface must warm to an average of about 59°F (with present-day concentrations) until enough energy can be emitted by greenhouse gases and escape to space to balance the energy being absorbed from the Sun.
Though these important greenhouse gases occur naturally in the atmosphere in varying concentrations, human activities are directly and indirectly increasing their abundance. In addition, other greenhouse gases not normally found in nature are being added to the atmosphere. The net result is to intensify Earth's greenhouse effect, causing Earth's surface to warm.
Let's pull it apart in detail:
"While it's not a perfect analogy" It's not only "not a pefect analogy", it's outright dead flat wrong. A normal greenhouse works by preventing hot air convecting away. As far back as 1909, Robert Wood disproved by experiment that "the glass makes it hard for the heat to escape" is the reason greenhouses get hotter. The get hotter because the prevent hot air escaping, period. To increase the offence this first flat out lie of a paragraph gives, NOAA have the audacity to persuade us with somethign they admit they themselves don't believe: "some say". Some say indeed! Obviously not them, they should be well aware of research done as far back as 1909!
"Certain naturally occurring gases in Earth's atmosphere have a similar warming effect on the surface. This warming is referred to as the "greenhouse effect," and the gases that trap heat are called "greenhouse gases."" No. Again, flat out dishonesty. (This is from a scientific organisation, so I omit the possibilities that they are ignorant, incompetent, or insane - only flat out dishonesty cuts the mustard.) The laws of physics are reversible. "Greenhouse gasses" absorb certain wavelengths of light in the infra red, and they radiate those same wavelengths. They don't "trap" anything. A trap is a one-way mechanism. Radiation physics says clearly that what you can absorb, you can radiate. They hedge their bet in the second half of the paragraph by returning (by implication only) to the correct laws of physics, but the damage, to a non-physicist reader, has already been done.
The third paragraph, of course, is not an answer to the posed question, but a gratuitous addition designed to make lay readers believe a problem exists. The question is not whether extra infra red-interactive gasses (IRIGs) increases their physical effect, but "how much"? The CO2 concentration right now is such that a light photon at the appropriate wavelength can't get 10 metres without being intercepted. The atmosphere is already 100% blocked by CO2 at the appropriate wavelength. Only the lightest change can happen now due to adding more plant food aka carbon dioxide. But of course mentioning that fact would spoil a good scare story.
No thanks, I'll stick to Doctor Who and the weeping angels when I want a good "science-based but not quite accurate" fright.
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