My theory is that climate scientists already know we're very much screwed, but they don't want to tell the world exactly how bad it is, for fear of inciting panic.
Technically, I think they have been telling us for a good while and people have just mostly laughed it off and called them irrational panic monkeys. I guess if nothing else, most people seem to accept that the climate is changing, now. The major point of resistance looks to be whether this is just a natural weather cycle and change, or if it is indeed manmade climate change. There's also a healthy side of 'What does it matter why it's changing? I'll be dead before it's all that bad so it's not really my problem to worry about.'
