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
click here to read article
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. :)
Here's a graph that nicely illustrates the point.
CO2 is a mere 0.038% of Earth's atmosphere!
Now, here is another piece of real physics the ManBearPig set rarely mentions at the journalist level.
The item whose response to changing atmospheric concentrations of CO2 is log, is a power term, as in watts.
It is not a temperature term.
The relationship between a change in power and a change in temperature is, itself, less than linear. Specifically, the power changes as the fourth power of the absolute temperature in degrees Kelvin (above absolute zero in other words). Therefore the temperature is going as the fourth root of the power.
And that is the proportional change in the total power. Which at sea level is on the order of 400 watts per square meter. (It is 240 for sunlight corrected for albedo - reflection, but greenhouse mostly from water vapor is added onto that, at sea level). The existing sea level average temperature is around 18C or 291 degrees Kelvin.
Thus, if I want a 1C change in average sea level temperature, I need a 292/291 proportional temperature change, which requires a (292/291) ^4 power change continually operating (to keep the earth glowing that much hotter), which is 1.38% more than I started with, or about 5.5 watts per square meter.
If the old power level from CO2 was say 2 watts per square meter, I can't get the next 2 watts just by doubling it, because the response is log. To get 7.5 instead of 2, I'd need to go far enough along a log curve to raise the Y axis 3.75 times. Which can be quite a long way.
Meanwhile, last physics point, the higher the atmospheric concentration of CO2, the faster CO2 is taken up by the oceans and other carbon sinks. This is because all the concentrations are set by "S curve" rate balancing, as in any chemical reaction system. Raise the partial pressure of CO2 on the "air" side of the ocean-air interface, from a previous equilibrium position, and more CO2 will diffuse into seawater per unit time than before.
In other words, there are restoring forces on atmospheric partial pressures, and it therefore takes an ongoing emitting source, not just a one-off impulse, to maintain a higher atmospheric concentration indefinitely.
So we are talking about changing temporary concentrations of a trace gas, on the order of less than a thousandth part of the atmosphere, then washing it through a log to get a power, than washing that power through a fourth root to get a temperature change.
There is a reason the ManBearPig set doesn't want to provide a power budget for their theories, and prefers regression lines drawn through noise, instead...
That other table early in the thread with the 0.117% CO2 effect is from the above site, linked in the article. Please note that the table is for the greenhouse gas EFFECT - not the amount of CO2 in the atmosphere. So while CO2 is only .038% of the atmosphere (mass? volume? does it matter?) - it becomes a WHOPPING 0.117% of the Greenhouse effect. I think that if we trash our economy in order to bring that number down by a third (to .078%) it will be well worth it.
(Ever notice the global warming sites ALWAYS refer to CO2 in terms of tons? There’s a reason for that!)
Thanks. Did you forget to put quote marks around “WHOPPING”, or do you actually believe that 0.117% is a “whopping” percentage of the combined GH effect (water vapor, CO2, Methane, etc)?
I believe 2112’s sarcasm was pretty obvious...
Especially the part about trashing our economy being worth it...
I figured that. I was mainly offering a ‘hint’ that it’s often best to add a sarc tag, quotes, or “lol”. Look at what happened to me earlier on this thread. Someone apparently thought I was a man-made global warming pusher because I talked about greenhouse gases.
Greenhouse gases DO exist, and literally thank God for His design of them, else we’d freeze when the sun went down.
However, there is a huge difference between talking about greenhouse gases and accusing man, in living our ordinary lives on this planet, of damaging it.
Actually, its effect can be calculated and water-vapor amounts to roughly 80%, rather than 90%. However, the alarmists dress the CO2 effect up by claiming that more CO2 raises temperatures and that puts more wv in the atmosphere. Of course, this neglects the sun-blocking effects of more cloud from higher humidity.
OK, 80%. So, during the most recent warming trend (which ended 11-12 years ago), when temps rose approximately 1 degree from about 1900-1998, you can blame, at most, 20% of the GH effect on non-water vapor greenhouse gases, which include natural CO2 and human-related CO2, plus Methane, Ozone/O3, and other misc GH gases, keeping in mind that not all this warming was related to GH gases at all, but many other sources/mechanisms. Doing the math, one would have to be insane to seriously believe that man-made CO2 was responsible for ANY significant warming during this time. Human-related CO2 would be a small fraction of this 20%. And this small fraction of 20% is responsible for what fraction of that measly 1 degree rise in temps? Can't be very much.
Are you new to this site?LOL!
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.You still didn't, or can't answer what the natural order of things was called before greenhouses were used. Or have you been brainwashed with "greenhouse gas" and "greenhouse effect"?
Say, what are you arguing?
Look at my #68 and tell me what you disagree with.
Science does advance over time. Not all of it is left-wing propaganda, like the BS that humans are responsible for “global warming”.
I really should have put the source in that picture. I’ve had it around for several years.
Some researcher was trying to get it through peoples thick heads in 2005 or 2006 that water vapor is the greenhouse gas.
A round of google searching might turn it up. If I get more energetic, I’ll try to find the source.
Published in 2003
here is the link
scroll down to number 5
Ping for later reference.
I have been looking for these references for a while.
Thanks for posting it
Science does advance over time. Not all of it is left-wing propaganda, like the BS that humans are responsible for global warming.LOL! Science advances but nothing is new under the sun including our weather and climate. To use "greenhouse gas" and greenhouse effect" is the language of the left AKA left wing propaganda. "Greenhouse gas" and "greenhouse effect" has negative connotations, using them to describe vapor is dangerous. If you don't believe that then you don't know what just took place with the EPA and CO2...The same onerous regulations can ultimately be applied to any greenhouse gas...You know, like water.
In fact water usage is already a topic at the EPA website under the global warming heading. It just isn't used there as a greenhouse gas...YET.
You might think you sound intelligent by saying that vapor is a greenhouse gas but I think you sound like brainwashed global warming dimwits....
Every major site or research group I know of that is arguing against man-made global warming recognizes that there are greenhouse gases. They just say that CO2 isn't a very important one here on Earth.
"Water vapour is the most important greenhouse gas. If you get a fall evening and the sky is clear, heat will escape, the temperature will drop. If there's cloud cover, the heat is trapped by water vapour and the temperature stays warm. If you go to In Salah in southern Algeria, they recorded at noon 52°C. By midnight, it's -3.6°C. It's caused because there is very little water vapour in the atmosphere and is a demonstration of water vapour as the most important greenhouse gas." (Tim Ball)
Water vapour is the most dominant greenhouse gas. Water vapour is also the dominant positive feedback in our climate system and amplifies any warming caused by changes in atmospheric CO2. This positive feedback is why climate is so sensitive to CO2 warming.
Water vapour is the most dominant greenhouse gas. The greenhouse effect or radiative flux for water is around 75 W/m2 while carbon dioxide contributes 32 W/m2 (Kiehl 1997). Water vapour is also the dominant positive feedback in our climate system and a major reason why temperature is so sensitive to changes in CO2.
Unlike external forcings such as CO2 which can be added to the atmosphere, the level of water vapour in the atmosphere is a function of temperature. Water vapour is brought into the atmosphere via evaporation - the rate depends on the temperature of the ocean and air, being governed by the Clausius-Clapeyron relation. If extra water is added to the atmosphere, it condenses and falls as rain or snow within a week or two. Similarly, if somehow moisture was sucked out of the atmosphere, evaporation would restore water vapour levels to 'normal levels' in short time.
As water vapour is directly related to temperature, it's also a positive feedback - in fact, the largest positive feedback in the climate system (Soden 2005). As temperature rises, evaporation increases and more water vapour accumulates in the atmosphere. As a greenhouse gas, the water absorbs more heat, further warming the air and causing more evaporation. When CO2 is added to the atmosphere, as a greenhouse gas it has a warming effect. This causes more water to evaporate and warm the air to a higher, stabilized level. So the warming from CO2 has an amplified effect.
How much does water vapour amplify CO2 warming? Without any feedbacks, a doubling of CO2 would warm the globe around 1°C. Taken on its own, water vapour feedback roughly doubles the amount of CO2 warming. When other feedbacks are included (eg - loss of albedo due to melting ice), the total warming from a doubling of CO2 is around 3°C (Held 2000).
The amplifying effect of water vapor has been observed in the global cooling after the eruption of Mount Pinatubo (Soden 2001). The cooling led to atmospheric drying which amplified the temperature drop. A climate sensitivity of around 3°C is also confirmed by numerous empirical studies examining how climate has responded to various forcings in the past (Knutti & Hegerl 2008).
Satellites have observed an increase in atmospheric water vapour by about 0.41 kg/m² per decade since 1988. A detection and attribution study, otherwise known as "fingerprinting", was employed to identify the cause of the rising water vapour levels (Santer 2007). Fingerprinting involves rigorous statistical tests of the different possible explanations for a change in some property of the climate system. Results from 22 different climate models (virtually all of the world's major climate models) were pooled and found the recent increase in moisture content over the bulk of the world's oceans is not due to solar forcing or gradual recovery from the 1991 eruption of Mount Pinatubo. The primary driver of 'atmospheric moistening' was found to be the increase in CO2 caused by the burning of fossil fuels.
Theory, observations and climate models all show the increase in water vapor is around 6 to 7.5% per degree Celsius warming of the lower atmosphere. The observed changes in temperature, moisture, and atmospheric circulation fit together in an internally and physically consistent way. When skeptics cite water vapour as the most dominant greenhouse gas, they are actually invoking the positive feedback that makes our climate so sensitive to CO2 as well as another line of evidence for anthropogenic global warming.
The Real ‘Inconvenient Truth’
Some facts about greenhouse and global warming:
From CO2Science.org, a somewhat more technical anti-man-made global warming site...
Results of a site search for “water vapor”:
Results of a site search for “greenhouse”:
Would the term “atmospheric blanket” be more to your liking?
I know the left has negatively connoted the terms “greenhouse effect” and “greenhouse gases” by using them in conjunction with their fearmongering,
but these two terms are actually a good description of what keeps the temperature of the earth more even/buffered with varying exposure to solar heat radiation, ie, night and day.
Like political correctness, the negative connotations of terms cease to have their effect when you refuse to acknowledge those connotations.
No argument from me.