Skip to comments.Water vapor accounts for a whopping 90% or more of Earth's greenhouse effect! CO2 very minor player
Posted on 02/15/2010 5:52:36 AM PST by ETL
Three article excerpts...
So, greenhouse [effect] is all about carbon dioxide, right?
Wrong. The most important players on the greenhouse stage are water vapor and clouds [clouds of course aren't gas, but high level ones do act to trap heat from escaping, while low-lying cumulus clouds tend to reflect sunlight and thereby help cool the planet -etl]. Carbon dioxide has been increased to about 0.038% of the atmosphere (possibly from about 0.028% pre-Industrial Revolution) while water in its various forms ranges from 0% to 4% of the atmosphere and its properties vary by what form it is in and even at what altitude it is found in the atmosphere.
In simple terms the bulk of Earth's greenhouse effect is due to water vapor by virtue of its abundance. Water accounts for about 90% of the Earth's greenhouse effect -- perhaps 70% is due to water vapor and about 20% due to clouds (mostly water droplets), some estimates put water as high as 95% of Earth's total tropospheric greenhouse effect (e.g., Freidenreich and Ramaswamy, 'Solar Radiation Absorption by Carbon Dioxide, Overlap with Water, and a Parameterization for General Circulation Models,' Journal of Geophysical Research 98 (1993):7255-7264).
The remaining portion comes from carbon dioxide, nitrous oxide, methane, ozone and miscellaneous other 'minor greenhouse gases.' As an example of the relative importance of water it should be noted that changes in the relative humidity on the order of 1.3-4% are equivalent to the effect of doubling CO2.
Water Vapor Rules the Greenhouse System
Water vapor constitutes Earth's most significant greenhouse gas, accounting for about 95% of Earth's greenhouse effect(4). Interestingly, many 'facts and figures' regarding global warming completely ignore the powerful effects of water vapor in the greenhouse system, carelessly (perhaps, deliberately) overstating human impacts as much as 20-fold.
Water vapor is 99.999% of natural origin. Other atmospheric greenhouse gases, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and miscellaneous other gases (CFC's, etc.), are also mostly of natural origin (except for the latter, which is mostly anthropogenic).
Human activities contribute slightly to greenhouse gas concentrations through farming, manufacturing, power generation, and transportation. However, these emissions are so dwarfed in comparison to emissions from natural sources we can do nothing about, that even the most costly efforts to limit human emissions would have a very small-- perhaps undetectable-- effect on global climate.
Water Vapor Confirmed As Major Player In Climate Change
ScienceDaily (Nov. 18, 2008) Water vapor is known to be Earth's most abundant greenhouse gas, but the extent of its contribution to global warming has been debated. Using recent NASA satellite data, researchers have estimated more precisely than ever the heat-trapping effect of water in the air, validating the role of the gas as a critical component of climate change.
Greenhouse Gas Absorption Spectrum
Figure 4 gives the amount of energy absorbed by greenhouse gases in various wavelength regions, from ultraviolet radiation on the left, to visible light in the middle, to infrared radiation on the right.
The CFCs are not plotted here but will be considered separately. For each gas is given a plot of the absorptance of the gas, ranging from 0 to 1, for each wavelength.
As an example, if we look at the plot for oxygen and ozone, we see that the absorption is very high in the ultraviolet region but essentially zero in the visible and infrared regions, except for isolated peaks. We interpret this to mean that this gas absorbs essentially all radiation in the ultraviolet but is transparent in the visible and mostly transparent in infrared portions of the spectrum. This gas then is responsible for shielding earth-based biological systems from lethal ultraviolet radiation, radiation with wavelengths less than 0.3 micrometers (or 300 nanometers), but allows visible light and infrared radiation to pass through without much absorption.
Other gases have much different absorption properties. Methane (CH4), for example, has a couple of very small wavelength regions in which it absorbs strongly and these occur at about 3.5 and 8 microns, which are in the infrared region. Nitrous oxide, N2O, having peaks at about 5 and 8 microns, absorbs in fairly narrow wavelength ranges.
Carbon dioxide has a more complex absorption spectrum with isolated peaks at about 2.6 and 4 microns and a shoulder, or complete blockout, of infrared radiation beyond about 13 microns. From this we see that carbon dioxide is a very strong absorber of infrared radiation. The plot for water vapor shows an absorption spectrum more complex even than carbon dioxide, with numerous broad peaks in the infrared region between 0.8 and 10 microns.
The total spectrum of all atmospheric gases is given in the bottom plot. This shows a “window” between 0.3 and 0.8 microns (the visible window), which allows solar radiation (without the lethal UV component) to reach the earth's surface. “Earth radiation”, the upwelling infrared radiation emitted by the earth's surface, has a maximum near 10 microns. The total atmosphere plot shows that a narrow window (except for an oxygen spike) exists in the range of wavelengths near 10 microns.
Sounds shovel-ready to me...
If there is no greenhouse effect there also can't be a greenhouse gas. Unless you are Algore or you work at the EPA water vapor is called evaporation, precipitation, weather...not greenhouse gas.
It is true that generally the climate changes when nature adds or subtracts water vapor...you know, like when it rains, or it's foggy...or not.
We see that water vapor not only absorbs more wavelengths, those wavelengths are shorter than those absorbed by CO2. Shorter wavelengths have higher energy than longer wavelengths. Thus H20 absorbs much more energy than does CO2. These higher energies are then converted into kinetic energy; heat.
That’s the only ‘science’ chart that needs ‘believed’! The rest are junk science, corruption, political ‘science’, cult, religion, etc. Algore is 99.72% snake oil salesman.
These higher energies are then converted into kinetic energy; heat.
There is ALWAYS a greenhouse effect taking place, be-it almost entirely due to water vapor, despite the fact that we've been in a cooling trend for the past 11-12 years. Without greenhouse gases, the planet would be freezing.
Here is one from 2007!
What does it take?
Two things are increasingly frustrating :
"Science" commentators on hundreds of TV stations still seem unaware that there has been a massive fraud for 20 years, and that the fraudsters have been "found out" beyond debate. These "readers" are science idiots who continue hawking "green energy", CO2 panic and business-as-usual neuroses about the discredited anthropogenic global warming."
Similarly, politicians at all levels seem impervious to reality, fraud and real scientists everywhere shouting at the top of their lungs that the onslaught of hysteria by politicians, and other non-scientist have brainwashed the equally ignorant populace with, is based on lies, ignorance and an agenda based on control, not pursuit of the truth.
Taxes confiscated from working Americans can be used more productively on other things; Trillions$ are being wasted and budgeted for future waste as we speak.
How can we stop these idiots?
In the lab, perhaps.
In the atmosphere, under the dynamics of complex weather, sunlight, cosmic rays and other solar system nasties we may not even know about, apparently not.
One of the qualities of real scientists is the ability to make a distinction between isolated lab experiments, and the identical few substances interacting with the thousands of different elements, compounds and factors in a real-time atmosphere.
The arrogance and ignorance of those claiming to mimic the complexity of weather, climate and the atmosphere on computer models which they write themselves --- is mind boggling.
Climate models, until recently, were claimed to be predicting future weather.
Since they have all failed, 100% of the time to do so, the claim has now changed to "projections!"
... which will continue to be wrong 100% of the time!
There is ALWAYS a greenhouse effect taking place, be-it almost entirely due to water vapor, despite the fact that we've been in a cooling trend for the past 11-12 years. Without greenhouse gases, the planet would be freezing.Nice try, greenhouse gas and greenhouse effect is a term you global warming pinheads coined and for some reason you choose to keep using it.
We haven't always had greenhouses. What was the natural order of things called before anyone knew what a greenhouse was? Condensation and evaporation?
CO2 can matter (though only marginally because it is so trace a gas) because the sky is largely "clear" in those wavelengths. But this changes as the CO2 level rises. The response is log rather than linear; the second doubling of the concentration does much less than the first. Close your window shades. How much would it matter if you hung 4 more sets of shades behind them?
Thanks! Are you in the field, or did you just sleep at a Holiday Inn last night? :)
Seriously. Thanks. Sounds like you know what you’re talking about.
Why do you ask?
Are you from the Bernie Ward School of argumentation?
And too lazy to find a refutation?
Or are you really and honestly eager to learn?
I should remind everyone that the criminal fraud "documenting" AGW was perpetrated by scientists who stonewalled legitimate FOIA requests to release the weather data and adjustments made to the world wide data observations made over the last 120 years; on which the IPCC based all their 100% wrong conclusions and their purely political recommendations.
It’s always a good idea to provide links along with info like that. Adds credibility and a chance for people to read more about it if they choose to.
Close your window shades. How much would it matter if you hung 4 more sets of shades behind them?
Expotentially less and less with each additional shade. Excellent point. Thanks again.
Although I totally agree, how many times does the same simple question be answered before it becomes simply a tool for distraction and delay? The ultimate pastime of the ignorant?
Perhaps a global warming "sandbox" is in order, for those honestly and seriously beginning science kindergarten.
I somehow missed this strange response of yours. First of all, what in hades makes you think I believe in man-made global warming?? Are you new to this site? I merely stated the fact that greenhouses gases do exist. Earth's temps fluctuate over time for many different reasons, ALL of them natural. Natural greenhouse gases, almost entirely water vapor, plays a major role, as does solar activity, cloud cover, orbital deviations, ocean current cycles and volcanoes.
I know. But not everyone here knows how logarithms work, or what the abbreviation “Log” stands for. :)
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