Here's a small example of why one should avoid getting their science from pseudo-scientists. Eric Worrall is criticising an experiment that was designed to determine the impact of higher daytime temperatures on bees.The scientists put some bees into boxes painted white and some into boxes painted black and monitored them for a couple of years.
Eric thought he found a fatal flaw. His criticism was this:
The team seem to have logged daily maximum temperature inside the boxes, but I didn’t see any attention to daily minimum temperature. Painting the boxes black would have caused higher maximum temperatures from absorption of sunlight in the daytime, but the black painted boxes would also have radiated heat faster at night.Just in case you thought, maybe Eric was talking about the faster rate of cooling as the sun went down, he's not. He added a sentence so you'll not make any mistake:
So it seems possible that much of the damage to the bees in the black boxes was caused by colder night time temperatures, rather than warmer daytime temperatures.Wrong! Both boxes would have around the same minimum temperature during the night.
Eric either didn't study radiation or he played up during the class and wasn't listening. Can someone tell him that in most places, the sun doesn't shine at night. Even if it did, the black boxes would absorb more sunlight and be warmer.
Perhaps Eric doesn't know that radiated heat from the boxes is in the infra-red range and the external colour of the boxes makes virtually no difference. The white boxes are the same as the black boxes when it comes to infrared radiation. In the daytime there is a heat difference because the white boxes reflect sunlight (visible spectrum), while the black boxes absorb it. Black boxes get hotter during the day. At night the temperature of both will eventually get to be the same as that of their surrounds. The black boxes won't get any colder than the white.
Don't just take my word for it, for the physically challenged there's even a paper :)
I'm not offering an opinion on whether the study itself is a good one or flawed, or whether the conclusions are sound. If you're interested, you can read the abstract and press release. I just wanted to point out that the criticism Eric leveled is no criticism and to show, again, that one shouldn't get their "science" from WUWT.
Ha ha! Excellent catch Sou. It is just such a good example of how deniers talk so confidently about radiation but do not really understand it. And then they double down on the flaws in their thinking when they are raised.
ReplyDeleteOf course EW will not double down on it ...
But as every bee psychologist could tell you (and there are many bee psychologists at WUWT), living in black boxes make bees depressed.
ReplyDeleteThe only surprise is that Eric spelt "bee" correctly.
I just love some of the comments reinforcing the misconception. Most of them miss that it is the relative change in temperature that is the issue.
ReplyDeleteI like this comment from a Bill T:
"I realize the study is of Mason Bees so things may be different, but I agree that it is a dumb study that fits well into “conformational bias”."
Ironic really with the confirmational bias criticism. If only those damned bees would conform.
Eric probably refuses to believe that the thermal systems on the satellites that relay his internet blatherings work. Those thermal engineers, always talking about alpha (absorbtivity) and e (emissivity) as if they were different! Everyone knows that reciprocity holds, so they have to be the same.
ReplyDeleteWell yes, even I was confused the first time I saw a presentation from thermal about satellite temperature control. But it only took me a few seconds of thinking to realize that the absorptivity matters for radiation from a 5000 K blackbody (the sun), and emissivity matters for radiation from a 300 K blackbody (the satellite). And yes, radiators on satellites are generally silver or white in color. Because yes, at 300 K the bulk of the outgoing radiation will be in the infrared (about 10 micron wavelength).
So to sum up: at the same wavelength, alpha and e are the same. But the incoming solar radiation is assuredly not at the same wavelength as the outgoing radiation. You'd think someone who had spent their lives talking about the greenhouse effect would know that.
isn't Eric just exposing the "common sense" view of science, such as heavy things fall faster than light things, the earth is clearly flat, CO2 is only a trace gas - I mean something's in science are just obvious
ReplyDeleteI found a copy of Carl Sagan's "Demon Haunted Earth" at a garage sale last week and brought it home. I have never read this book before, but he does an excellent job of calling out the pseudoscience claims that so many are so inclined to accept.
ReplyDeleteBy now, everybody knows that WUWT is the last bastion of fools, idiots, connedspiracy theorists and stupidstitious fanatics. Or they should. Your not going to find intelligent life there. It's as devoid of life as the Moon.
What's so pathetic is they're just totally unwilling to admit to facts and abuse the very concept of scientific investigation to prove their claims. Sagan has a lot to say about these soothsayers, who simply want you to accept their dribble and deny any evidence to the contrary.
But perhaps the worst part is this - it's malicious deception deliberately being foisted to prove falsehoods. They're dead wrong, and have always been dead wrong, about climate change - and will do virtually anything to keep spewing their lies and spinning their "evidence".
Malicious deception on critical science facts and evidence isn't harmless and has a lot of ramifications. This why they are dangerous fools - they have an agenda to keep people deliberately misinformed.
I'm waiting for them to jump on the record cold temperatures measured in Antarctica.
ReplyDeleteWUWT is the last bastion of people willing to claim the Trump inauguration was the biggest evah. No wonder they are also willing to publish this rubbish.
ReplyDeleteFortunately for Climate Etc., there's enough rubbish to go around.
DeleteWhen faced with a critical comment that appears to be the only deviation from WUWT's usual crankfest, Worrall replies:
ReplyDeleteBlack surfaces radiate heat faster at night, unless they have been treated with pigments to make them white in infrared. This would have caused the nests to lose heat faster on cold nights.
I wonder if Infrared White can be copyrighted as a color name? Infrared White, Ultraviolet Black, X-ray Blue, Radio Red... Worrall's a genius.
"Black surfaces radiate heat faster at night ..."
DeleteI knew it!! Faster than light speeds is possible.
But everybody knows who has used an infrared sensor that infrared is green!!!!!!!
DeleteEric has confused his partial knowledge of black body radiators with the pigment.
ReplyDeleteSou is absolutely correct that at night the colour of an object as far as long wavelength IR radiation is immaterial.
A black body absorber/radiator is a mythical mathematical construct. It is simply defined as the perfect radiator at all wavelengths and absorber at such.
Sou as usual has nailed his lack of expertise.
Bert
I don't think this is quite right. Color does effect emissitivity, and that changes radiated IR. A darker box will emit more IR at night. That's why radiators and heat sinks are sometimes blackened.
ReplyDeleteHowever, once you reach ambient, it doesn't matter. Emissitivity is exactly the same in both directions, and IR energy is flowing in from backradiation as well as out. At ambient temp, the change in emission due to differing color will be exactly balanced by the change in absorption of backradiation, so the box will stay at ambient temp.
A different color could affect the rate at which a box cools to ambient, but it can't make it cool to below ambient. If the two boxes start at the same temp, the black box will reach ambient first. However, since the black box starts out hotter here, it will probably reach ambient after the white box, despite a faster rate of cooling.
Sorry, that is incorrect. Read some of the other comments here, including mine above. Radiative heat transfer happens at the temperature of the object that's radiating, which in this case is the box, which is about 300 K, where most of the emitted energy is in the IR, peaking about 10 microns wavelength.
DeleteThe emissivity at 10 microns is completely uncorrelated with the emissivity in visible light. 10 microns is 100 times longer wavelength than visible. The emissivity at those two wavelengths is controlled by entirely different physics.
Here's an example from my field:
"AZ-93* is an inorganic white thermal control paint developed for use on spacecraft / satellite surfaces exposed to the deleterious effects of the space environment. Application of AZ-93 creates a nonspecular white coating that provides superior thermal control / protection by allowing only 14-16% of the solar radiation impinging on the spacecraft external surface to be absorbed through to the interior systems while emitting 89-93% of the internal heat generated to the cold vacuum of space."
Gregory's comment has some misconceptions, similar to Eric's.
DeleteHere's another article to complement what Johnny Vector said:
"Almost all common surfaces are ‘black’ around 10μm. If we look up their emissivity at such wavelengths, we find values near 1 for almost anything: Common paints have value around or above 0.9, irrespective of colour. Even water and glass fall into that category,with emissivities well above 0.9."
https://www.europhysicsnews.org/articles/epn/pdf/2007/01/epn07102.pdf
We were trying to design a Bolometer that relied on amorphous gold coated onto the detector in a partial vacuum that led to the blackest surface then known.
ReplyDeleteWhat was really happening all radiation that fell on this random surface of gold atoms were absorbed because they could not get out.
It was then the ideal blackest coating close to the theoretical black body.
This has now been surpassed by a forest of carbon nanotubes that are even a better EM trap. Bert
Yes Bert. Very impressive. But what about the bees? Will no-one think about the bees? :)
DeleteThe key point to me is not that Eric was wrong. But, like all his friends and colleagues at WUWT, Eric thinks he knows more about the experiments off the top of his head than actual expert scientists who worked on the project for years. Chutzpah or Dunning-Kruger or both?
ReplyDeleteA lot of it is motivated reasoning. The scientists are wrong or else WUWT and its sheeples have been part of something whose consequence is appalling to contemplate.
Deletegooooood
ReplyDelete