[Hunble]

lower concentration of the carbonate ion CO3^2.

An ion has one extra neutron in it's atom. So CO3^2 is rather rare and unusual.

Did you pay attention to the actual article? They were not talking about normal CO2, but a very rare and unusual ion.

[spunkets]

"An ion has one extra neutron in it's atom. So CO3^2 is rather rare and unusual."

? No. I think you need to learn some chemistry first.