There is more evidence that global warming is real and worse than previously thought. The Earth's temperature is rising nearly 1 degree Farenheit per decade.
That's a pretty alarming rate of change. It means that the average temperature of the Earth could change by as much as ten degres F in a single human lifetime.
To put this in perspective, it is probably not a coincidence that the rise of argiculture and civilization coincided with the end of the last ice age about ten thousand years ago. It's not so much the warming up per se that allowed civilization to arise, but rather the fact that global temperatures remained relatively constant for ten thousand years. It's hard to build a civilization if the city you build today will be underwater (or in the middle of a barrent desert) by the time your grandchildren grow up.
Ice core evidence shows that the last ten thousand years have been unusual in the grand and glorious scheme of things, and that radical global warming and cooling have been the rule rather than the exception. That has led some people to be complacent about mankind's contribution to the recent round of global warming, saying that this is just the Way Things Are. That may be. It may also be that civilization now has a firm enough grip that it will survive the end of the conditions that allowed it to arise in the first place, much like a plant, once established, can survive a drought that might have killed it as a seedling.
But even the hardiest plant cannot survive a drought forever.
Global climate change has the capacity to subject us to stresses that we as a species have not known for five hundred generations, possibly within the lifetime of some people alive today. That is certainly a worst-case scenario, but it is not outside the realm of possibility.
One reason to be optimistic: we will probably run out of oil first.