To the best of my understanding, the main leaders of the environmentalist movement have made a conscious decision that whipping people into a state of alarm and panic about the prospects of catastrophic climate change is not the right way to go. Instead, there’s a preference for focusing on the positive and trying to paint an appealing vision of the clean energy future. And though it’s not something I’ve peered into in great detail, the research in social psychology seems to me to back that conclusion up — it really is better to focus on the positive political message rather than trying to freak people out.
That said, the trajectory we’re on right now is actually really frightening. The weather seems like a banal topic, but if you study history it’s clear that systematic changes in the climate can have utterly catastrophic impacts on human societies. And it’s also clear that right now climate-related issues are having a significant negative impact on human lives. If you want to give yourself a good scare, Stephan Faris’ book Forecast: The Consequences of Climate Change, from the Amazon to the Arctic, from Darfur to Napa Valley is all about reportage on this sort of thing and the scary near-future we seem to be heading towards.