Is carbon dioxide equally distrubuted throughout the Earth?

[nst.john]

Is carbon dioxide at relatively the same concentrations in China, America and Antarctica for example? Or (I'm not discussing altitudes) does the concentration of carbon dioxide fluctuate based on where you are on the Earth? Assuming that all measurements are made at the same altitude, would the levels of carbon dioxide be different in different places throughout the world and why?

 

[Borek]

No, it is not identical everywhere, there are both regional and seasonal differences.

 

[nst.john]

What are the regional differences and what drives them?

 

[czelaya]

It may help to incorporate that oceans are large CO₂ emitters.

 

[Borek]

I don't know exact numbers, but carbon dioxide is both produced and consumed by vegetation, in different amounts depending on weather/season, so the rainforest and the desert must differ.

 

[Borek]

It may help to incorporate that oceans are large CO₂ emitters.

Are you sure they are net emitters, and not absorbers?

 

[nst.john]

I think oceans are absorbers, isn't that why we have coral reef bleaching?

 

[D H]

It may help to incorporate that oceans are large CO₂ emitters.

The oceans are large CO₂ emitters at upwellings. However, the oceans are even larger CO₂ sinks. As a whole the oceans currently absorb slightly more carbon from the atmosphere than they emit into it. The land (and the land-based biomass on/in it) is also currently a net absorber.

This is on a year-to-year basis. The balance varies significantly on a season-to-season basis because of land-based biomass.

 

[nst.john]

Does temperature decide where carbon dioxide is eitther emitted or absorbed more from water and/or land?

 

[D H]

CO₂ solubility in water increases with decreasing temperature (and vice versa). The colder parts of the oceans absorb CO₂ from the atmosphere. Upwelling of cold, CO₂ laden bottom water into warmer waters causes the upwelling water to release CO₂ to the atmosphere.

On land, plants grow and absorb CO₂ in the summer, but not in the winter. Rotting (which releases CO₂ to the atmosphere), on the other hand, happens to some extent year-round.

 

[czelaya]

The oceans are large CO₂ emitters at upwellings. However, the oceans are even larger CO₂ sinks. As a whole the oceans currently absorb slightly more carbon from the atmosphere than they emit into it. The land (and the land-based biomass on/in it) is also currently a net absorber.

This is on a year-to-year basis. The balance varies significantly on a season-to-season basis because of land-based biomass.

Thank you. When Borek asked the question I wasn't sure. I attempted to look it up and the answer was not straightforward.

Do you have any links or papers you can link on oceanic CO2 emission/sinks?

 

[nst.john]

No I have none. Does anyone have any? I'll look it up.

 

[D H]

Google the term "carbon cycle".

 

[nst.john]

http://m.earthobservatory.nasa.gov/Features/CarbonCycle/
This one explains it not only qualitatively but quantitatively. Also http://www.nature.com/nature/journal/v408/n6809/full/408184a0.html
Which talks about the correlation of global warming and carbon cycle feedbacks


Mentor note: The first link doesn't work for me, but I'm not on a mobile device. This link does work for me: http://earthobservatory.nasa.gov/Features/CarbonCycle/

 

[Borek]

On land, plants grow and absorb CO₂ in the summer, but not in the winter.

Yes, that's what I referred to speaking of seasonal differences. There are daily cycles on top of that, and even change in weather can be an important local factor. In farmlands even the way land is used (crop, crop type, pasture) yields changes in the local carbon dioxide levels.

Typically these are averaged, they just make reliable measurements more difficult.