There is no cap and trade on SO2. Were there it would have been used to support CO2 cap and trade!
It is clear that the planet has gone through cycles like this before and that such cycles could not have been caused as Goreites believe by little ole us. Also there is no real compelling evidence that we are the cause either. In this decade it was reported that an error had been made and the hottest year on record was 1934. Yet now the data for this decade does nothing but increase each year, defying the logic of natural events. And in contrast to the actual temperatures that have been declining. Cows pump millions of tons of chemicals into the atmosphere, as do trees. In fact every living thing adds its share toi the environment. Who are we to claim that intimate knowledge of such an organism is ours to know, when we do not even know all the parts of said organism!