We have on a small scale. Methane is escaping as the permafrost thaws. Boreal forests are also burning down as their climate warms. Reduction in polar ice changes the albedo of the earth to reflect less heat.
At a certain point sufficient warming could trigger a cascade. So far we haven't done that, but it's incorrect to say there's been no release of stored CO2.
At a certain point sufficient warming could trigger a cascade. So far we haven't done that, but it's incorrect to say there's been no release of stored CO2.