Does the percentage increase of CO2 reduce the percentage of other greenhouse gases ?

[Icemelt]

In the past 4,000 years the concentration of CO2 in the atmosphere increased from 277ppmv to 379ppmv which increased its atmospheric percentage concentration from 0.053% to 0.054%. It therefore follows that that the concentration of some or all of the other constituents must have reduced by a compensating amount.

 

Since CO2 is not the most powerful of GHGs, it is very possible that the concentration of other GHGs will have been reduced, dampening the effect of the increase in CO2. For instance if water vapour were to decrease by 0.01% this would more than offset the effect of any CO2 increase.

 

Do we have any data on this ?

[insane_alien]

they might decrease in relative composition but there wouldn't be any change in actual quantity. the atmosphere wold get thicker and have a reater insulating effect.

[bascule]

Are you familiar with the concept of a non-sequitur?

[KLB]

they might decrease in relative composition but there wouldn't be any change in actual quantity. the atmosphere wold get thicker and have a reater insulating effect.

 

Another way to think about it is that the total amount of greenhouse gases would increase as relative percentage of the atmosphere. Think of it this way, if you have six inches of highly efficient foam insulation in your attic and then add six inches of low efficiency fiberglass insulation in your attic, while the percentage of insulation that is foam insulation goes down, the total amount of insulation increases thus increasing the total heat retention capabilities of the attic.

 

While I'm not sure I could successfully find a peer reviewed paper on it, one should ask the following question. When we burn fossil carbon, we are getting the carbon in the CO2 from sequestered sources, but where does the oxygen come from?

 

For every atom of carbon that is released from fossil fuels, two atoms of oxygen must come from somewhere to produce that CO2. The source of that oxygen is the atmosphere. It would be entirely reasonable to expect that as the total number of CO2 molecules in the atmosphere increases from the burning of fossil fuels, the total number of O2 molecules in the environment would decrease by the exact same amount (1 C + 1 O2 = 1 CO2). So in the end, one would expect the total amount of O2 in the atmosphere to decrease as the CO2 increases from the burning of fossil fuels (lets just hope that O2 doesn't drop below 19.5%).

[ecoli]

Other greenhouse gases may be less abundant, put actually are stronger greenhouses then CO2, on a per molecule basis. A mole of CFCs trap a lot more heat energy than a mole CO2, for example. There is a hell of a lot more CO2, though, so this contributes a lot more.

 

It's important not to ignore other Greenhouse gases, in any case.

[jackson33]

KLB; i wouldn't worry to much about oxygen, as its the most abundant thing found on the planet. although 22% of the atmosphere, its found in all things and actually represents 46.6%. the next thing is silicon at 27.6. this according to *amistupid.con* on a google check some time ago. what is interesting Carbon is listed as a "other" which makes up in total 1.4% of the total.

 

carbon, is however a stored element of all plant life and found on many materials. in the process of creating energy, the removal of that carbon is produced by heat which requires 2 molecules of oxygen to produce that CO2. in burning a tree, coal or any fossil fuel, but the oxygen in that item also is involved or released.

 

now, photosynthesis is the reverse process, taking 6 molecules of H2O or water and six of the CO2, splitting carbon, for storage or its use as stored carbon, producing one molecule of sugar or for the plant or fruit of the plant and releases 6 molecules of oxygen. since oxygen is so prevalent in nature, i am not sure its mathematically possible to figure out the end results of one process to the other. however trees, especially the large ones, store or hold this carbon for very long periods. think its said there is 600 billion tons of carbon now in storage, which is trivial to the tons stored in the oceans with are use by sea life.

 

my argument opposed to trying a world wide attempt to reduce for natural causes anything is in the levels of CO2, which is the food for the equilibrium of oxygen producing plant life, which relies on those few particles which are needed to maintain the storage. the storage is to plants is the abundance of oxygen that exist for us. plants or nature, with a shortage will just cause plants to die off and furnish its own CO2, by the decaying process.

 

if there is a point in this seemingly rant; nature itself, has a means to correct and re-correct conditions to the current state. the over all state of no importance, as we exist from eons of slow change, at least to nature.

[KLB]

KLB; i wouldn't worry to much about oxygen, as its the most abundant thing found on the planet.

I was being a little sarcastic about the 19.5% thingy. If we converted enough O2 into CO2 to bring the atmosphere down to 19.5% I'm quite certain we would have already faced other existence threatening problems.

 

although 22% of the atmosphere, its found in all things and actually represents 46.6%. the next thing is silicon at 27.6. this according to *amistupid.con* on a google check some time ago. what is interesting Carbon is listed as a "other" which makes up in total 1.4% of the total.

My own stats on the periodic table on my environmental chemistry site shows basically the same thing so we are in agreement on this. Keep in mind that all of that oxygen is locked up in chemical compounds in the earth and not readily available.

 

if there is a point in this seemingly rant; nature itself, has a means to correct and re-correct conditions to the current state. the over all state of no importance, as we exist from eons of slow change, at least to nature.

The problem is that nature corrects and compensates over eons of slow change. If we royally screw things up rapidly, we could do ourselves in before nature could compensate. Our actions or lack of actions could have bad consequences.

[Icemelt]

Are you familiar with the concept of a non-sequitur?

 

I am now !

 

However it would be rather interesting to see a chart depicting the atmospheric makeup over say the past million years.

 

I can't help feeling there could be a surprise or two hiding there.

[1veedo]

There are records in ice core samples. The only gases that they include are usually methane and CO2 but if you look at one of the more popular reports it might have with it a data set of various other gases. I wouldn't know where to begin looking though, except if anyone wants I can hunt up a couple titles. One I know is in nature and it costs like $6 or something to get full access to (if you don't subscribe to Nature which is like $100 or something).

[jackson33]

I am now !

 

However it would be rather interesting to see a chart depicting the atmospheric makeup over say the past million years.

 

I can't help feeling there could be a surprise or two hiding there.

 

if billion, maybe yes; however a million years is a fraction (55 Million) which mammals have existed, even man. surely the basic content have moved in favor of life forms of today but probably no major changes...

[Icemelt]

if billion, maybe yes; however a million years is a fraction (55 Million) which mammals have existed, even man. surely the basic content have moved in favor of life forms of today but probably no major changes...

 

Yes I would agree that we should examine a longer period, but I've been criticised in the past for producing 550 million years charts, so I thought a million might be more acceptable.

 

From the chart below you will see there would obviously be a very dramatic change in the percentages of constituents over the past 500 million years.

 

[Icemelt]

There are records in ice core samples. The only gases that they include are usually methane and CO2 but if you look at one of the more popular reports it might have with it a data set of various other gases. I wouldn't know where to begin looking though, except if anyone wants I can hunt up a couple titles. One I know is in nature and it costs like $6 or something to get full access to (if you don't subscribe to Nature which is like $100 or something).

 

Yeah, methane has just a few months half life though, so not really too interesting. I'm thinking that the percentage of oxygen has radically changed in the past 50 or 100 million years, so I guess all the other constituents have too. And the water vapour figures would be very interesting if they are available. How much is the subscription to nature and what's the url ?

[1veedo]

Yes I would agree that we should examine a longer period, but I've been criticised in the past for producing 550 million years charts, so I thought a million might be more acceptable.

I think you're criticized more for using log charts ;P. The greater-then-10-or-so-million-year charts are going into other climatic periods so in relation to global warming they really can't tell us much -- on this level we're talking about climate change that occurs (literally) as fast as the continents can move or the moon can recede from the Earth.

 

In this case I think your "long" graphs would be perfectly acceptable.

 

Btw the idea about gases pushing out water vapour is really kind of illogical because water vapour runs on completely different cycles from other gases. I don't know where you're going with this but water is kind of "absorbed" by the atmosphere and it comes and goes pretty quickly (it doesn't have a half life, it just rains when temperatures drop and evaporates when temperatures rise).