I honestly think humanity will remain more adaptable than global warming's ability to effect us is. At the end of the day, we will be fine. We have recognized and prevented threats of similar situations in the past, and will continue to in the future. Even today renewable energy is growing faster than coal, and it's only getting better as time goes on. Remember that most power comes from coal, not oil. The price of coal needs to drop to effect it's use. The price of natural gas is already incredibly low (AFAIK), so it's not as if it being lower will bring it into adoption faster.
It's not about us. It's about the millions of species that will go extinct without ever having been discovered. It's about the lifesaving medicines that have yet to be found. It's about not fucking up the planet so royally that the only things that can live on it are humans, and whatever other species we deign to keep alive for our own amusement.
Life will survive us, most likely. Even if we undertook measures to erase everything with DNA we could find, including ourselves, something, somewhere would survive. But is that the legacy we want? That of the asteroid that offed the dinosaurs?