Subject: 3% CO2 remains in H2O as carbonic acid; rest 97% in a closed vessels?

CO2 as green house gas is a serious problem. I read an article by Mr. Dan 
Berger, Faculty Chemistry/Science, Bluffton College, ID: 892859430.Ch
that  "---only about 3% of dissolved CO2 will remain in water in the form of 
carbonic acid". 
So, I was trying to understand, if CO2 passed through water in a closed vessel, 
(1)how much CO2 will get absorbed and how long it remains in water and 
(2)what happens to the rest 97%  CO2 if the vessel is closed one.

Re: 3% CO2 remains in H2O as carbonic acid; rest 97% in a closed vessels?