You hear fewer people talking about "global warming" these days and more using the term "climate change." This is a neat tactical segue: a cold spell (such as 2013, one of the coldest years on record) can no longer be used as evidence against global warming, but is now in fact "evidence" of climate change.
This allows liberals (and this is an issue on which thought generally falls along the political divide) to shake their heads and mutter ominously whenever it's colder or warmer than usual for that time of year. (Liberals are never wrong.)
I know one such liberal who used to grumble whenever it was warmer than usual for that time of year. Now she can shake her head about our climatical Armageddon whenever there's any sort of weather pattern.
The fact is, we've always had weather that varies from the norm; otherwise we would never have needed weather forecasts. (And boring conversationalists like myself would never have anything to talk about.)
I'm agnostic myself on whether man is causing any sort of large scale change. It's certainly possible that all this burning of fossil fuels could be having an effect on the environment. But there are an almost infinite number of factors involved, I don't know nearly enough to have an informed opinion, and neither do most of the people who believe in climate change with almost religious certitude.
The best measure of their religiosity is how angry they get when you tell them you're agnostic on the issue. The above-mentioned liberal once screamed at me and told me to get my head out of my ass when I took that position.
I might as well have told a Muslim that Allah does not exist.