better start burning lime thenThe carbon locked up in fossil fuels, of which we can only lay our hands on a relatively small percentage to release, is a tiny insignificant blip compared with the carbon which has been locked up in calcium carbonate over the same millions of years, and carried on doing since the evolution of fungus stopped the production of the fossil fuels.
Eventually, there will be so much carbon converted into seashell and then chalk that there will not be enough carbon dioxide left to come out of a naturally occuring ice age. Or if it does, it will be life in a very different form from what we have now.