Such is the nature of life, so far. Hopefully, we can leave enough evidence that they can draw their own conclusions, but anything we can say from our graves will likely be met with tons of skepticism. For the most part. Whether we do something about it or not, we as a species can look forward to some pretty drastic lifestyle changes, either self-induced or forced by our environment. While we can manipulate our environment, I personally don't think we're smart enough yet to manipulate it enough to forestall something as big as global warming, even if we are mostly responsible for it.
Historical inevitability is, after all, inevitable.
I think I'll go read the Foundation series again.