Throughout Earth's climactic history it has seldom been the warming that has been a serious threat to life on earth. The threat has often been the rapid onset of global cooling that follows a global warming.
It may turn out the global warming people are quiet because its over. Too late to try to do anything now.
The bottom line is these things don't happen over night or in a generation of any living species, but they definitely happen over and over again.
The thing I do agree with that the global warming people can prove is that there has been an increase in the time table for temperature climb, showing a quicker heat up than what history shows is the norm. Because of that, I personally believe there will be the opposite effect in the cool down this time....a fast freeze, or sudden drop compared to the climactic historical charts average.
What goes up must come down and what goes up fast comes down faster, unless you slow it down....which is what the global warming buffs were talking about the whole time....slowing something down.
The people who believe in global warming are half right, those who don't believe it are half wrong. It's just the way it is. Our problem is our need to be right all the time. :)
In my opinion this is one of those topics humans waste too much time and effort on when there are bigger fish to fry.