No, Obama's policies regarding the climate will not change the world. I believe that policies that hurt economic growth in order to reduce carbon emissions are bound to be short lived, and make little impact to the environment overall. Developing countries already ignore carbon emission laws, and are a major part of the problem as well. I think that true change will come from individuals and small groups working together, and deciding to live more efficient and environmentally friendly lives.
The rest of the world does not have the benefit of spending more money and cutting themselves off from the easiest supplies of energy. Reducing use of coal in the energy sector is going to cost us money that we do not have. Other countries will see the strain that it puts on our wallets and not follow suit. We can tout our greenness to the entire world, but the fact is the rest of the world is going to do what is cheap and easy.
Since in his new policy he left most of the changes to be elected by the states, I highly doubt that most of the states will elect to adapt to his new policies. The policy will cut jobs and will raise utility costs. Very few states will adapt and this will just be another failed Obama policy.
Obama's ideals and motives are sound and on paper could be impactful. However, like most of his initiatives, they get very little traction. Unfortunately his climate change policy will have little effect, especially since he is rolling it out in the twilight of his tenure. I realize that presidents like to make a legacy policies at the end of their term but this is just "bs" politics at work. If he was truly serious about climate change then he would have put at least some of the polisies in motion long ago. In the end, Obama will be remembered not for changing the world with climate policies but with starting and never finishing much of anything.