What's the relationship between CO2 and Temperatures?

Question

What would the temperature of the climate be if co2 levels doubled?

What would the temperature of the climate be if co2 levels were reduced by 50%.

Please post the supporting math that shows your work.

Answer 1

There is now potential to estimate photosystem II (PSII) activity in vivo from chlorophyll fluorescence measurements and thus gauge PSII activity per CO2 fixed. A measure of the quantum yield of photosystem II, ΦII (electron/photon absorbed by PSII), can be obtained in leaves under steady-state conditions in the light using a modulated fluorescence system. The rate of electron transport from PSII equals ΦII times incident light intensity times the fraction of incident light absorbed by PSII. In C4 plants, there is a linear relationship between PSII activity and CO2 fixation, since there are no other major sinks for electrons; thus measurements of quantum yield of PSII may be used to estimate rates of photosynthesis in C4 species. In C3 plants, both CO2 fixation and photorespiration are major sinks for electrons from PSII (a minimum of 4 electrons are required per CO2, or per O2 reacting with RuBP). The rates of PSII activity associated with photosynthesis in C3 plants, based on estimates of the rates of carboxylation (vo) and oxygenation (vo) at various levels of CO2 and O2, largely account for the PSII activity determined from fluorescence measurements. Thus, in C3 plants, the partitioning of electron flow between photosynthesis and photorespiration can be evaluated from analysis of fluorescence and CO2 fixation.

hope i didn't make it too complicated

Answer 2

Dana said:

"2) If CO2 levels doubled from 280 to 560 ppm and nothing else changed, global temperatures would increase roughly 3 deg C."

Wow, where did you hear this? Even the IPCC puts a CO2 doubling *with feedbacks* at 3 deg C. Supposedly, if CO2 levels doubled from 280 to 560 and everything stays the same, global temperatures would increase by roughly .5 to 1.2 deg C. Of course there is no way to know this, because it would never happen in the real world.

Answer 3

Well I think I will give you a star for this question, since it prompted me to do some research, to seek out a useful equation or model.

Here is a "primer" on some of the math and concepts involved.  http://www.nationalcenter.org/NPA420.pdf

∆F = 6.3 ln (C/C0) w/m^2

where ∆F is the change in forcing, and C0 and C are the initial and final carbon dioxide concentrations

When C/C0 is 2, ∆F is 4.4 w/m^2, and when C/C0 is 0.5, ∆F is -4.4 w/m^2.

The change in surface temperature, ∆Ts, is given by:

∆Ts = ∆Q [ ∆F / ∆Ts  - ∆S / ∆Ts  ]^ -1

where ∆Q is the net downward radiative flux and ∆S is the change in the downward solar radiation at the top of the atmosphere.

The primer refers to simplified data from the 1991 IPPC report, for a calculated temperature change of 1.9 degrees C for a doubling of CO2 concentration using the previous formula, neglecting the effects of cloud coverage.

The real answer would have to be based on an accurate model, which would take into account many more formulas and calculations than could possibly fit here.  

You know most of us here aren't actually scientists.  I hope you are not trying to suggest that global warming can't be real just because we can't do all the math on it, especially by hand.

Answer 4

CO2 has very little to do with the earth's temperature. It keeps the temperature steady but what makes the temperature rise and fall is the temperature of the Sun, how much energy it emits.

Answer 5

Well even though I'm wasting my time, the answer is:

1) CO2 is a greenhouse gas.  When its atmospheric concentration increases, so do global temperatures.

2) If CO2 levels doubled from 280 to 560 ppm and nothing else changed, global temperatures would increase roughly 3 deg C.  If you want to see the math, read the studies listed here:

http://members.aol.com/bpl1960/ClimateSe...

Once again, just because the math and science is complex doesn't mean it's wrong.

3) If CO2 levels were reduced by 50% and nothing else changed, global temperatures would be roughly 10 deg C colder.  That's not exact, because I don't feel like doing the math, but you can see the calculation herea:

http://www.mit.edu/people/goodmanj/terra...

Answer 6

It wouldn't help much as most of the greenhouse gases in the atmosphere are methane and other gases. CO2 is a small part of the problem.

Answer 7

There is no mathematical relationship between the two, because we don't have the proper statistics. You have to be able to model this information somehow to derive an equation ... Based on the information we possess on the link between CO2 and temperature increase, there can be no such equation.

Maybe in a few hundred thousand years, someone can give you a good answer to that.

Answer 8

Many studies site an increase of 36% since 1990--- of CO2 concentration--- and I really do not see any dramatic temperature increase during this time frame(very short time frame)--- if it dropped by 36% I would probably ALSO see no impact????

However I get your point--- the computer models are BOGUS!

Answer 9

CO2 is produced by all animals, plants, and microorganisms, and is part of the photosynthesis  cycle where plants absorb it and release oxygen. The oceans absorb much CO2 in a process that’s called hydration.

The relation between temperature and CO2 is that CO2 increases lag temperature increases by 800 which is due to sea temperatures. The ability of sea water to absorb CO2 is dependent upon the water temperature. Colder temperature seas can absorb more CO2, so when the temperature goes up, it does not absorb as much CO2 so that the surrounding air has a greater concentrations of CO2.

Al Gore has this relation backwards. He thinks the an increase in CO2 increases temperature.

Answer 10

it would be freezing all te time

Answer 11

Great question

I will not show the math, but it is available on the web from most skeptic websites.  Most of the calculations place the CO2 effect of 1 deg C +/- .5 deg C.  We also may currently be .5 degree C there.  By the way I find very little other than skeptic websites when i search the first law of thermo and global warming.

As I am sure you know CO2 effect will not be linear.  So cutting CO2 in half should decrease the temperature more than doubling increases it.

Answer 12

Dude no one's answering your questions seriously.

There's no math needed. CO2 levels has nothing to do with global warming. it's a natural cycle dated back hundred of years ago. and the phenomena we are now experiencing is the peak of warm age the opposite of ice age. I think it's halocene epoch if I'm not wrong

Answer 13

The answer to both is 'minimal'.

By adding 183,000  ppm. CO2 to the atmosphere, the temp. would rise by a degree.  It's estimated that so far in history man has added about 58,000  ppm. CO2, which barely changed a thing.  If we burned all fossil fuels on earth we would not achieve a one degree difference.

Answer 14

The IPCC gives a value of 4.3 W/m2 for the radiative forcing of doubling the concentration of atmospheric CO2 (which represents a warming equivalent to approximately 0.4% increase in incident solar radiation).  

The earth is cooled by a combination of convection, conduction and radiation and convection and conduction increase in proportion to the temperature and heat loss for radiation is proportional to the temperature to the power of 4.  If we look at what would happen to the Earth if it were cooled entirely by radiation and what would happen if it were cooled only by convection and conduction, the change in temperature would be somewhere between.  If the Earth were cooled by convection only the change in temperature would be 0.4% of 293K and if radiation were the only cooling, the temperature change would be  (1.004^-4 - 1) x 293K (293K being the approx average temperature of the Earth).

Based on the IPCC's figures, the temperature increase of the Earth is predicted to be between 0.29 and 1.2 degrees K.

A lot of people dispute the IPCC's radiative forcing figures and the IPCC never published their working for how these figures are derived.  The author of the attached link has estimated that the IPCC's radiative forcing factor for CO2 is too high by a factor of 85.  He does show his working.