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150th Anniversary of Greenhouse Climate Theory
An anonymous reader writes "It was 150 years ago that John Tyndall, one of history's truly great physicists, published a scientific paper with the far-from-snappy title On the Absorption and Radiation of Heat by Gases and Vapours, and on the Physical Connexion of Radiation, Absorption, and Conduction. The BBC has an article on John Tyndall and his contributions 150 years ago to the physics behind the study of climate change."
What truly makes me sad when I see things like this, is that it ultimately makes me think that a bit of science has been lying around for 150 years - and there are still people who try to disclaim it, pretend it simply isn't true and make all manner of excuses as to why it doesn't mean what it clearly states. All to either keep making money, keep doing what they have been doing or because it is simply easier to not have to change the way things are done.
Moved to http://soylentnews.org/. You are invited to join us too!
The basic science of global warming isn't too tough or very modern(clearly), although most people don't understand it very well. This article seems to make things fairly confusing as well, although the quote from Tyndall himself is pleasantly concise and clear: "heat in the state of light finds less resistance in penetrating the air, than in re-passing into the air when converted into non-luminous heat." My favorite explanation, I think, is how Carl Sagan explained it in Cosmos, which is roughly as follows:
The idea is that visible light hits the earth, and warms it up. Some of that light is reflected straight back, so it leaves the atmosphere the way it came in and we're done. A lot of that light, though, gets absorbed by trees or rocks or walruses, causing them to heat up. They'll slowly re-radiate it out again because of blackbody radiation (all things radiate continually, even the universe itself) but it will be in the form of lower energy, lower frequency wavelengths. This means that energy from visible light gets absorbed and often radiated back out again as infrared.
CO2 and other "greenhouse" gases let light in the visible part of the spectrum pass unimpeded, but they don't let IR through as easily. So, energy comes in but it can't get back out again.
Svante Arrhenius "was the first to calculate on the heating of the Earth in 1903. But, he refers to Fourier, Pouillet and Tyndall as predecessors. He was the first person to predict that emissions of carbon dioxide from the burning of fossil fuels and other combustion processes would cause global warming. Arrhenius clearly believed that a warmer world would be a positive change. From that, the hot-house theory gained more attention. Nevertheless, until about 1960, most scientists dismissed the hot-house / greenhouse effect as implausible for the cause of ice ages as Milutin Milankovitch had presented a mechanism using orbital changes of the earth (Milankovitch cycles). Nowadays, the accepted explanation is that orbital forcing sets the timing for ice ages with CO2 acting as an essential amplifying feedback.
Arrhenius estimated that halving of CO2 would decrease temperatures by 4–5 C (Celsius) and a doubling of CO2 would cause a temperature rise of 5–6 C.[5] In his 1906 publication, Arrhenius adjusted the value downwards to 1.6 C (including water vapour feedback: 2.1 C). Recent (2007) estimates from IPCC say this value (the Climate sensitivity) is likely to be between 2 and 4.5 C. Arrhenius expected CO2 levels to rise at a rate given by emissions in his time. Since then, industrial carbon dioxide levels have risen at a much faster rate: Arrhenius expected CO2 doubling to take about 3000 years; it is now estimated in most scenarios to take about a century."
Some quotes:
"To a certain extent the temperature of the earth's surface, as we shall presently see, is conditioned by the properties of the atmosphere surrounding it, and particularly by the permeability of the latter for the rays of heat." (p46)
"That the atmospheric envelopes limit the heat losses from the planets had been suggested about 1800 by the great French physicist Fourier. His ideas were further developed afterwards by Pouillet and Tyndall. Their theory has been styled the hot-house theory, because they thought that the atmosphere acted after the manner of the glass panes of hot-houses." (p51)
"If the quantity of carbonic acid in the air should sink to one-half its present percentage, the temperature would fall by about 4; a diminution to one-quarter would reduce the temperature by 8. On the other hand, any doubling of the percentage of carbon dioxide in the air would raise the temperature of the earth's surface by 4; and if the carbon dioxide were increased fourfold, the temperature would rise by 8." (p53)
"Although the sea, by absorbing carbonic acid, acts as a regulator of huge capacity, which takes up about five-sixths of the produced carbonic acid, we yet recognize that the slight percentage of carbonic acid in the atmosphere may by the advances of industry be changed to a noticeable degree in the course of a few centuries." (p54)
"Since, now, warm ages have alternated with glacial periods, even after man appeared on the earth, we have to ask ourselves: Is it probable that we shall in the coming geological ages be visited by a new ice period that will drive us from our temperate countries into the hotter climates of Africa? There does not appear to be much ground for such an apprehension. The enormous combustion of coal by our industrial establishments suffices to increase the percentage of carbon dioxide in the air to a perceptible degree." (p61)
"We often hear lamentations that the coal stored up in the earth is wasted by the present generation without any thought of the future, and we are terrified by the awful destruction of life and property which has followed the volcanic eruptions of our days. We may find a kind of consolation in the consideration
What are the causes of global warming? I don't think that it is settled that human activity is the SOLE cause.
If you believe the IPCC report, then you can be assured that it IS settled that human activity is the primary cause.....or at least, very likely. Here is what it says:
"Most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations."
"First they came for the slanderers and i said nothing."
Just who worships Al Gore? This must be some obscure subculture or something because I don't really know anyone who thinks very highly of Gore (they may not dislike him, they may even have some basic respect for things he's done but they don't put him on a pedestal).
Or maybe it's like the Michael Moore thing, where lots of right-wing idiots (and trolls) thought everyone left of Mussolini worshiped Moore even though the reality of it was that we were slightly impressed by his documentaries but still had some issues with the movies as well as with Moore himself.
Greylisting is to SMTP as NAT is to IPv4
... spend their time building straw men to burn, rather than trying to understand where the disconnect in communication is :)
You know that burning straw men in arguments is very bad for climate change, right?
"Historical records have had the average temperature warmer than now"
That may be true in another world of the many-worlds multiverse. Not this one.
Not globally, not even for the Northern Hemisphere, not for any climatically meaningful interpretation of "now".
Really, people, this is not hard. Google for Spencer Weart, read his website, then google Skeptical Science and read John Cook's web site.
"the ice caps . . . just three years ago, people were claiming they'd be gone in six [years]..."
Aha. I see the problem: reading comprehension. It was not ice caps but Arctic sea ice that was exercising the imaginations of bloggers. Cryosphere researchers expect the ice caps to last thousands of years -- tens of thousands of years, in the case of the Antarctic ice cap.
using words like truther and denier just brings in stupid partisan bullshit in what SHOULD be a healthy debate
This would be much more convincing if the rest of your post weren't exactly the kind of ignorant, paranoid rant that causes people to be labeled deniers in the first place.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Actually, look closer at your graph - we've done B, and we've gotten less than C.
http://stevengoddard.wordpress.com/2011/01/20/rommcook-prosecute-themselves/
The fact that when he "put the graph at the same scale as Hansen’s predictions", the measured temps of the past don't even remotely match up shows he's full of it. And if you fell for it, you are even dumber than I thought.
Fandroids hate facts.
Well first of all I think using words like truther and denier just brings in stupid partisan bullshit in what SHOULD be a healthy debate.
I agree, but that's the sort of thing that happens when it's long past the time that "healthy debate" should have ended. Suppose every test indicates you've got cancer, and every doctor you've seen says you've got cancer. Locking into the position that you don't have cancer is not "healthy debate". It's very unhealthy debate, especially when the tumor is visible on your skin.
Now here is what I personally have against the whole climate change, which make up your damned mind is it global warming or global cooling?
Strawman and beside the point. global cooling was never a widely accepted theory
Climate change is a cop out, the climate has been changing for all of recorded history!
Also beside the point. Climate is changing at an unprecedented rate. This change is dues to human CO2 emissions.
The ONLY "solution" we have been offered is carbon credits
Beside the point, and entirely untrue. It's beside the point because you're using your displeasure for the solution as evidence the problem doesn't exists. Carbon credits were chosen by politicians as the only solution that would satisfy conservatives. Many other solutions were offered. They were all rejected because they weren't "market based". Frankly, a revenue neutral carbon tax is a better solution, but conservatives wouldn't go for it because it has the word "tax" in it. But, even if the solution was free donuts, I'm guessing you would oppose it.
Support SETI@home
Rev Al Gore
Stopped reading here. You ask people to quit calling names like "truther" and "denier," then go on and do the same fucking thing. You're part of the problem you're complaining about.
--Jeremy
Jesus was a liberal