EXXON Contradicts its Own Scientists

[_Themis]

Brad,

I wasn't the one claiming that 4% was the maximum saturation point for water vapor in air. Obviously that isn't true.

If you think that's been my claim, you've misunderstood. I've said several times that 4% represents fully saturated air at around 86 degrees. Your chart confirms that.

I've also referred to sources that describe the water vapor content of the atmosphere as ranging from 0% to 4%, depending on local temperature and relative humidity.

My actual claim is that your claim that water vapor is 4% of earth's atmosphere is absurd.

The problem may have occurred when I addressed this after Tobin brought up 4%. Here is Tobin's post.

When you are talking about gases that represent mere parts per million and billion, it is very fair to state they have negligible effects on global warming. Water vapor represents often 4% of the atmosphere per volume. If there is a greenhouse gas of significance, that is the one. And as I've also pointed out, good luck getting people to rally around the cause of removing water from the atmosphere. It's a ridiculous notion.

I questioned the often remark when I brought up that it would be much less then 4%, but Tobin only said it would often be found at 4%. Still not sure what often means since most of the atmosphere is no where near 30C.

[_The CCC]

Themis:

In my little area of the atmosphere 30C is usually called summer.

[_Res Ipsa]

Sometimes it helps to stop and summarize a position. I've been posting for several pages now in response to this argument by Tobin (which appeared in several different posts):

...CO2 is such a tiny part of our atmosphere (less than 1/100th of 1%), it can't do much on its own. The major greenhouse gas in the Earth's atmosphere is water. After the Sun, it is the primary cause of global warming. That is why I get a chuckle out of you global warming nuts. If people found out that you wanted to rein in the SUN and WATER, you'd be laughed out of the room.

...Which number is bigger? .4/100th of 1% or 4%? Which number do you think represents CO2? Which number is H2O? Which one is significant? Which one is insignificant?

Tobin has not provided any evidence that water vapor comprises 4% of the total atmosphere.

My first counterargument is that the amount of greenhouse gas presently in the atmosphere is not the sole factor that determines whether a greenhouse gas is "significant." Tobin eventually admitted that two other factors are relevant: the absorption spectrum of the gas and the distribution of the gas in the atmosphere. When we evaluate how much adding a greenhouse gas to the atmosphere will warm the atmosphere, there is an additional factor: the length of time that the added gas will stay in the atmosphere. This is referred to by climate scientists as "residency."

My second counterargument is that Tobin's 4% figure for the percentage of water vapor in the atmosphere is overstated by an order of magnitude.

1. Most sources give the range of water vapor in the air as ranging from 0% to 4% (I've seen some go as high as 5%). Tobin has picked the high end of the range and claimed it is the average.

2. To get 4% water vapor in air, you need a minimum temperature of around 30C (85F)

3. The global average surface temperature is around 15C.

4. At 15C, assuming 100% humidity, water vapor is about 1%.

5. As we leave the surface of the earth, the temperature starts to drop at the rate of around 5 degrees per kilometer, reducing the capacity of the air to hold water vapor.

6. At around 5KM (depends on where the measurement is performed), water vapor diminishes to the same density as CO2. From there on up, there is more CO2 than there is water vapor.

7. The total mass of water vapor is about .3% (I've used the highest figure I found -- others are lower) The total mass of CO2 is .06%

I'm going to add a third: Tobin has understated the percentage of CO2 in the atmosphere by an order of magnitude. 400 ppm does not equal .4/100ths of one percent. It equals 4/100ths of 1%, or, .04%

So, using the figures Tobin said in his post, he claims that there is 1000 times the amount of water vapor in the air than there is CO2. The actual evidence shows it is around 5 times. The difference in volume is certainly not enough of a difference to claim both that water is the most significant greenhouse gas and that CO2 is "insignificant" To determine the "significance" we will also have to take a look at the radiation absorption spectra and distribution of the two gases in the atmosphere.

Tobin has responded to my counterarguments with to counter-counter arguments:

1. If you heat the air enough, it is capable of holding 10% water vapor.

2. Air can be supersaturated with water vapor.

To those arguments, I respond:

1. Of course. But that would require conditions that simply don't exist on earth. 10% water vapor would require a temperature of 122F with 100% humidity.

2. Supersaturation of about 1-2% is observed in clouds. However, humidity of less than 100% is also observed in clouds. The condition occurs when warm, moist air is rising and cooling. If a nucleus (dust, aerosol particle, etc.) is not present, the temperature can drop so low that the relative humidity exceeds 100%. However, the amount of water vapor in that rising air has not increased at all. The increase in relative humidity is entirely due to the falling temperature.

Tobin has presented no evidence that either of these factors has any significant impact on the total amount of water vapor in the atmosphere.

[_Tobin]

I'll admit that .4/100ths isn't correct and it should be 4/100ths.

With that out of the way, at 4 or 5% water vapor in the atmosphere, that is over 100 times the amount of CO2.

Now, to deal with the silliness of Brad's argument here:

1) Most climatologists recognize that water vapor is the chief greenhouse gas in the atmosphere. And while residency has applicability to CH4, it really isn't meaningful as a criticism of the existence of water vapor in the atmosphere since water is so prevalent that water vapor is usually always present in the atmosphere except the driest desert locations.

2) Brad relies on global averages. However, one has to ask why he's doing that? After all, global averages include winter months in which global warming isn't really a factor since direct sun light isn't very prevalent to cause much warming in most northerly and southerly locations. Also, these averages wouldn't apply to intertropical and tropical convergence zones where high temperatures and high humidity are prevalent. Since this area represents over half of the world's surface, it is hard to imagine that theses zones wouldn't be a significant contributor to global warming all year long.

Second Amendment) Also, as I've pointed out, winter doesn't contribute much to global warming. However, summer months in northerly and southerly locations would contribute the most to it. Since these months have much higher temperatures and humidity, it would seem that the high range of water vapor in the air being a major contributor to that warming is appropriate.

3) Brad brings up that higher altitudes have less water vapor and so heating would primarily be due to CO2. While this may be true, the problem is there is nothing to retain the heat and it would be radiated back into space at night. Higher temperatures near the surface is a concern for global warming since land masses and water retain that heat at night contributing to the problem.

I hope anyone with a modicum of common sense can see that Brad is being disingenuous with his supposed facts in the extreme. I believe it reflects a nutty religious agenda and a highly biased view of the facts with almost no correlation with reality to promote the supposed harm caused by CO2 while ignoring the significant contribution of water vapor to global warming. The reason for this religious agenda should be clear since it is absurd to believe humans at this point in our technological development can control how much water vapor is present and so it is absurd to believe we can have a meaningful impact on controlling how much global warming there is in general. And he is doing this only to promote his nutty view that we should stop using carbon emitting energy sources to control global warming. However, it should be clear that at the levels of CO2 currently in the atmosphere (or the amount that could ever be produced in hundreds of years of continual use of carbon emitting sources) that doing so won't have any significant impact on global warming at all.

[_The CCC]

Water vapor is temperature dependent. At a given temperature the air can only hold so much water. On average winters are getting warmer.
SEE http://www.weather.com/science/environm ... ming-trend

[_Gunnar]

However, it should be clear that at the levels of CO2 currently in the atmosphere (or the amount that could ever be produced in hundreds of years of continual use of carbon emitting sources) that doing so won't have any significant impact on global warming at all.

If this is so clearly true, why is it that almost all the scientists who (unlike you) have actually spent their careers studying physics and chemistry of climate and all the factors that influence in great depth that you have not even begun to approach disagree with you? Do you honestly think you are smarter and/or more knowledgeable than them? A reasonable person would think that if AGW were really as baseless as you insist it is, the consensus confirming it would become steadily weaker with time instead of stronger, unless one assumes that 97 to 98% of all the scientists in the entire field climatology are either incompetent or dishonestly conspiring to deceive the world or both. Is that what you believe? That resembles nutty religious zealotry far more than what we have been saying!

[_Tobin]

Gunnar,

Please read the following link:
https://en.wikipedia.org/wiki/Argumentum_ad_populum

You keep making this fundamentally fallacious argument.

[_The CCC]

Gunnar,

Please read the following link:
https://en.wikipedia.org/wiki/Argumentum_ad_populum

You keep making this fundamentally fallacious argument.

Classic Red Herring, and Reductio ad Absurdum.

[_Tobin]

Classic Red Herring, and Reductio ad Absurdum.

That is an unsubstantiated claim since his argument meets the classic definition of Argumentum ad populum. If that isn't factually true, please demonstrate how it isn't. I bet you can't.

[Guest]

I'll admit that .4/100ths isn't correct and it should be 4/100ths.

With that out of the way, at 4 or 5% water vapor in the atmosphere, that is over 100 times the amount of CO2.

Except that water vapor is almost never at these concentrations even in warmer areas of the world. Don't make your usual mistake in thinking myself or others are arguing that water vapor doesn't create most of the contributions to heating the planet.

Now, to deal with the silliness of Brad's argument here:

The main problem here that he understands is that you do not understand what he is arguing for and what he is not arguing. The percentage of water vapor has been a bit of a distraction due to your incorrect understanding of how much is present in air. You mistakenly think people are arguing against water vapor being the largest contributor to temperature. All you want to assert without any evidence is that CO2 contributes so little that the increases we see will cause little warming. You have never backed this up. To back this up all you need to show is scientific research showing how much each green house gas contributes. Others including myself have, but we all know you didn't really go over those links to the actual science. How much does the science calculate that CO2 will warm the planet? There are links in this thread that can help you understand better how much and how they work.