Ternberth et al. spent a decade developing and then refining this "energy budget" as better satellite and other data became available. It is widely cited in climate literature. Of the 396 W/sq. meter infrared radiation emitted by the earth's surface, all but 63 is already absorbed in the atmosphere and re-emitted toward the earth as global warming. The "atmospheric window," a range of frequencies in which greenhouse gases have little effect and in which CO2 has virtually none, accounts by their measure for 22 watts/sq. meter. Of the remainder, almost none remains in the frequencies affected by CO2.
Fig. 1
19 comments:
I sent your analysis to my grandson who is a scientist an here is what he thought of your analysis of global warming.
Gloria Levitt
"Bullshit. Through and through. His argument is that we have saturated the damage we can do with CO2. (IE, if we add more CO2, it won’t do any more damage). The issue is he only considers the incoming sunlight (new heat). This matters because the earth has already absorbed a ton of heat over the last 100 years (a fact evidenced by the rising global temperatures). Adding more CO2 to the atmosphere may not continue to absorb any external sunlight, but will continue to exaggerate the “greenhouse” effect, preventing the heat that the earth has absorbed form leaving.
Best,
Drew"
Dear Gloria: Your grandson is probably speaking of "downwelling" of infrared radiation from the stratosphere into the troposphere (where it could affect climate) as saturation extends into the stratosphere, and to infrared frequencies where saturation by CO2 is not yet complete. Downwelling is already reflected in the described relationship between increase in Radiative Forcing and CO2, and which is trending toward flatlining. As for the incomplete frequencies, water vapor steps in to absorb much if not all of what CO2 doesn't, and increasingly large increases in CO2 are required to affect them because CO' ability to absorb is much weaker there. This too is reflected in the existing data. Eventually absorption by increases in CO2, already dwindling greatly, must dwindle to zero as the quantity of CO2 required to move the needle further becomes almost impossibly huge.
The Atmosphere has specific heat factors. Isn't that the overriding factor of heat absorption?
Take a house heater. It has a very large black-body emission curve:
http://www.intechopen.com/source/html/38093/media/image6.jpeg
It doesn't matter what the CO2 levels are within ppm parameters, the same heat relative heat BTUs are required to get the air to the preset temperature from the Thermostat.
Consider Venus. It is hot not because the atmosphere is almost pure CO2 but that the atmospheric density is approximately 97x that of Earth's. This follows the gas laws.
If you look at the Venus atmospheric lapse rate, when you get to a pressure level that is of Earth's, the temperature is almost that of Earth's average.
So CO2 is not the GHG that it's made out to be. In fact the green house theory is just bunk.
Dear Harold in your blog you assert that increasing concentrations of carbon dioxide from todays levels make no difference to the amount of Radiative Forcing (RF). As I said before you might want to read this paper (particularly figure 6):
https://www.researchgate.net/profile/Joanna-Haigh/publication/258816506_The_greenhouse_effect_and_carbon_dioxide/links/5b6583a1aca2724c1f20d610/The-greenhouse-effect-and-carbon-dioxide.pdf?origin=publication_detail
“as the atmospheric CO2 concentration rises from zero the total (instantaneous) RF at first grows very sharply but the rate of increase moderates such that for concentrations between about 30 and 800ppmv RF increases in proportion to log(mixing ratio).” We are currently at just under 420ppmv and rising....
The authors conclude, contrary to your blog, that: “as the concentration of CO2 in the Earth’s atmosphere continues to rise there will be no saturation in its absorption of radiation and thus there can be no complacency with regards to its potential to further warm the climate.”
Dear Max: Thank you for posting here so I can respond. Please excuse my delay in responding.
First let me clear up an apparent misunderstanding. I did not and do not say increasing CO2 above current concentrations makes no difference to RF (radiative forcing, i.e. global warming). I did and do say RF increase is following a logarithmic curve that is ever more flattening towards the infinitesimal as CO2 increases.
I also observe that there is some cap to further increases in RF when all the available radiation that can be absorbed by CO2 is absorbed, which should be obvious unless one proposes that CO2 can violate the known laws of mathematics and physics. The paper you reference concedes the concept of saturation, which it concurs has taken place in the central part of the range of infrared frequencies where CO2 absorption is strongest and most influential. The significant disagreement between blog and paper is that the latter claims that cap would not be reached even if the atmosphere somehow became 100% CO2. I am not prepared to prove or disprove that calculation, so I have amended this essay to leave the cap concept out. It is not needed in any case because the logarithmic curve RF is following dwindles toward the infinitesimal as concentrations increase.
That brings me to the part of the paper you reference headed “Climate radiative forcing by carbon dioxide,” which could create a false impression if a reader is not careful. It uses a theoretical measure to calculate RF by CO2 at various concentrations and frequency ranges and results are depicted in Figs. 6a, 6b and 6c.
In 6a it sets out RF by CO2 up to 2,000 ppm. The graph closely agrees with the familiar logarithmic curve empirically measured up to present levels, but predicts a divergence, starting at about 800 ppm, between RF caused in the range around 15 microns (the major CO2 absorption range by far) from the total absorption by CO2 throughout the infrared spectrum. This is because increasing saturation flattens the 15 micron curve. Obviously, the overall curve is the more important, but apparently many climate-change models use only the 15 micron range, presumably because the other ranges are so minor in importance. Note that this graph is linear, not logarithmic.
In 6b you see alarming-looking upward curves and an even more alarming-looking divergence between 15 microns alone and total RF. But look again. This graph is logarithmic, not linear. Each unit of concentration increase is actually a tenfold increase over the one before, vastly compressing the chart. So the line representing the 15 micron range, which in fact is flattening out, appears as rising steadily at a nearly 45% angle. If it were linear, like the 6a panel and using the same measure, 6b would have to extend out for 500(!) panels instead of one. I leave it to you to think about how slow RF increases must become to accommodate this graph. Consider 6c, which sets out calculations of the contributions of different frequency ranges to further increases in RF. The line for the core frequencies of the 15 micron range flatlines at zero quite early on, reflecting saturation. The paper describes the divergent all-infrared line back in 6b as “supra-logarithmic,” but in fact the 15 micron line is SUB-logarithmic because of this flatlining, for the logarithmic curve RF is presently following theoretically continues at decelerating rates out to infinity.
Since CO2 levels are currently about 425 ppm and have only rarely and comparatively very briefly exceeded 2,000 ppm in the last 200 million years, and at current rates of increase would take many centuries to do so again, it is the region in 6a that is relevant to present discussion.
If CO2 is able to 'absorb'(sic) blackbody radiation from Earth and re-emit it in EVERY DIRECTION, including 333 units back towards Earth, then by exactly the same physics, CO2 is able to 'absorb'(sic) incoming solar infrared radiation, 1000x than blackbody, then re-emit it in every direction, including 333,000 units (by this example) back into space, for net SHIELDING effect that increases 'shading' as CO2 levels increase. I've never seen the atmosphere energy balance include CO2 'resonant forcing' even consider the obvious re-emittance of solar infrared energy by at least 60% of incoming, BACK TO SPACE (since Earth is a sphere, not a plane.)
Your stuff is from 2008? it is way out of date!
Our injection of additional CO2 into the atmosphere and marine environments has destabilized the Stable State of the Climate, which is the resultant of interactions between complex systems.
Conditions will start to change, to oscillate between extremes greater and greater until it finds a new Stable State, usually at one of the extremes, where it gets stuck. It may not be conducive to Human habitat.
Harold, how many humans were alive when we had 2,000 ppm?
I see those of us who can contest your assertions are not allowed to post.
Typical.
Not true either. Please refer to the IPCC
To Peter Torbay: CO2 acts like insulation. Insulation retards transmission. Does your attic insulation absorb all that heat? Nope, it blocks it.
"If CO2 is able to 'absorb'(sic) blackbody radiation from Earth and re-emit it in EVERY DIRECTION,"
Nope. It does not absorb it, it blocks it.
So it also blocks incoming solar radiation?
So it blocks incoming solar radiation?
Regardless of whether or not we humans are, via the use of fossil fuels contributing to heat driven climate change, given the multitude of other environmental problems brought about either directly, or indirectly by the extraction and use of fossil fuels, we would be wise to terminate our dependence upon fossil fuels as soon as possible.
If my memory is correct, water pollution, ''regardless of the source of said pollution,'' causes more deaths every year around the world than is caused by warfare, and violent crime combined. While water pollution is not in every case caused by the extraction nor the use of fossil fuels, both activities are known to be significant sources of water pollution. This being the case, the development and use of cleaner energy sources, coupled with a commitment to more frugally consume energy, have to be considered worthwhile endeavors.
Anonymous, it interferes with infrared light, not visible or ultraviolet.
The Creator Incorporated CO2 in the air and for us to expel for a reason. We know that green things also grow better. It also acts as a protection for plants as heat intensifies. It seems it has no effect on the overall temperature.
The Creator knew what He was doing when climate was created as a changing atmospheric condition during the years. Man cannot begin to change what He so greatly and perfectly created.
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