Whether it escaped from a lab or came from grossly unsanitary practices at a meat market, neither of those has anything to do with "deforestation."
In addition, both Bloomberg and Steyer spend over a billion dollars combined on their respective presidential runs, claiming global warming was a big part of why they were motivated to run for President. Have they donated anywhere near the equivalent amount to a forestation project in Africa? A billion dollars could plant several entire large forests. That would have more environmental benefits than just any issues with so-called global warming and would be very much a worthwhile project - certainly more than a billion dollars worth of television ads. But did they do that?
They could have also gone into numerous, entire poor rural American towns and offered to fully renovate totally broken down homes and make them more energy efficient. Did they do that? No, they spent it on TV ads.
There are actual real things they could have done to greatly so-called "greenhouse gases". But no, they spent it on TV ads. Difficult to believe they are sincere.
This is like the Al Gore criticism.
Here's youtube mini-debate about how the liberal rich say they want to pay more taxes, but don't pay more taxes now when they can.(they want ours to be raised)
Stephen Moore nukes MSNBC Chris Hayes on rich liberals wanting to pay higher taxes (7/8/12)
Hayes :"The point is that there's something called social policy, social policy is something that you want to see put into the social contract, the reason you want to put in social contract is because it has the force of coercive law,the force of coercive law is the way that we bind each other each other and to democratic governments .....(interrupted making brilliant point) "