Absolutely:

http://en.wikipedia.org/wiki/Buffer_solution

The same thing happens with CO2.

Natural systems are capable of absorbing a certain amount. For example you can put a certain amount of CO2 into the ocean and it will be buffered by calcium and precipitate as calcium carbonate or be taken up into shells.

But add more than that amount and the water becomes acidic decreasing the effectiveness of the uptake mechanism. This is what we are seeing.

Here is another example of the concept. Lets say a square meter of soil can absorb into ground water 1 liter of water per hour.
If I start dribbling water into that square meter at the rate of 1cc/min it is all absorbed. 5cc/min. 10cc/min. etc. At some point I overwhelm the ability of the ground to absorb the water and no matter how much more I add all it does it run off.

That is what is happening to the atmosphere. We have overwhelmed the ability of natural systems to sequester CO2.


DA Morgan