Question on water vapor?

Question

Is it true that 96% of all global warming is caused by water vapor? Was this in Al Gore's movie?

And water vapor warming isn't caused by us right?

Answer 1

The amount of water vapour in the atmosphere varies, the average is about 1% by volume but in areas with 100% humidity and high temperatures the volume can be up to 4%.

It is by far the largest component greenhouse gas by volume but it's also the weakest of the greenhouse gases. Different greenhouse gases are better than others at trapping heat, the effectiveness is measured on a scale which takes carbon dioxide as having a value of 1 and is called GWP or Global Warming Potential.

Some greenhouse gases have a GWP 100,000 times that of water vapour (these are the CFC's, HFC's and HCFC's which have now been banned). Carbon dioxide, methane and nitrous oxide are the three main anthropogenic greenhouse gases, all of which are far more effective at contributing to the greenhouse effect than water vapour.

Whilst volume is important this has to be taken in context along with GWP.

It's also important to remember that water vapour forms part of the natural water cycle and has an atmospheric life of approximately 4 days, this compares with 115 years for carbon dioxide and thousands of years for the CFC's.

There's also a maximum amount of water vapour the atmosphere can contain, once the maximum is reached the surplus falls to earth as rain. There is no such mechanism for offloading excess greenhouse gases so these just pile up in the atmosphere and have a cumulative effect.

Nature is incredibly efficient at dealing with natural cycles and these are finely balanced, when humans come along and upset these cycles is when things go horribly wrong. Water vapour is part of a natural cycle, greenhouse gas emissions aren't.

--------------

Edit re your added comment...

The amount of water vapour we produce is miniscule compared to natural sources. Virtually all water vapour in the atmosphere is the result of evapouration from the seas and oceans. The mean mass of atmospheric water vapour is in the order of 12.5 quadrillion tons - that's roughly 2 billion tons for every person on the planet; even if every one of us boiled a ton of water into steam every day for the rest of our lives it would make almost no difference.

Answer 2

At least about 36–70% should be water vapor Is Naturally. There might be more water vapor if you count the clouds.
There should be about 9–26% carbon dioxide (CO2) naturally.
Anything more that that for CO2 is what is suppose to be a main causing Global warming.

Answer 3

NONE of the global warming currently occuring is caused by wator vapor.

Here's why:

The gases that make up the atmosphere act as a "blanket"--keeping the earth's average temperature constant. One of those is water vapor. Now, as long as the composition of the atmosphere remains CONSTANT, there will be no change (at least from changes in the atmosphere) in the earth's temperature--it reached an equilibrium long ago.

Now--the proportion of the earth's atmosphere that is water vapor has not changed in the last couple of centuries. So it cannot have caused the temperature of the Earth to change--and therefore is NOT a cause of global warming. The only part of the atmosphere that has changed is tthe increase in CO2--and that has been proven to be due to the massive release of CO2 (roughly 25 billion tons annually) as a result of our use of fossil fuels.

Answer 4

Yes it is true however the natural global warming process prevents our earth from global cooling. On the other hand if humans add to the global warming done by nature, a simple increase in 3 degrees Celsius in ocean temperature will cause major disasters like hurricane Katrina. As you can see nature does its own job of keeping the climate stable but humans interfere it severely by causing the slightest addition or reductions to earths natural processes. Nature does global warming to its own benefit but human activity causes nature to overdo it and cause disaster. As you can see nature is fragile.

Answer 5

Moisture is a liquid in gas answer. some volume of water(liquid solute) is soluble in air(gaseous solvent) searching on the temperature & rigidity circumstances in that section and could grow to be a answer.

Answer 6

that's not true, global warming is caused by the burning of co2, and the gas eating away at the ozone layer it has nothing to do with water vapor

Answer 7

I believe a large portion of it deals with warming agents too close to the ground.

if it were higher, say...in the ozone, we would solve two problems.

Answer 8

No, it is not true.
Water vapor in the atmosphere has not changed- it is a circulating process.