I have a nasty secret.

It’s ugly.

It’s embarrassing.

I don’t want to even tell you. But I feel I must:

I sometimes question anthropogenic global warming.

I know, I know. AGW must be true; it’s what all these guys agree on. And, forgetting all the messy details for a sec, AGW just makes sense: If humans send a bunch of gases into the air that wouldn’t be there naturally, it’s bound to have a deleterious effect.

But there’s a lot of people out there who don’t buy it. From scientists who publish peer-reviewed work (though relatively few) to clowns that post in “Comments” after seemingly every climate-change article on the Web, there’s a broad spectrum of skepticism. And it gives me pause, to be honest. Can all the deniers really be in cahoots on some sort of agenda? Can all these voices, some with very respectable pedigrees, be that off the mark?

I asked colleagues at the Society of Environmental Journalists (I use the term loosely; I’m a colleague of theirs only inasmuch as they were kind enough to accept a neophyte, smacking-of-bandwagon wannabe journalist into their respected group, whose members include many reporters who’ve been working the environment beat for 20-plus years and from whom I’m constantly learning) if they ever wavered in their belief of the AGW consensus, and what “one, definitive source” initially convinced them.

Not one of the handful of SEJ members who weighed in said they doubted the AGW consensus, and most said narrowing it down to one source was impossible, because being convinced of AGW means understanding the science, which means following the countless peer-reviewed studies over the years, or, as one member put it, the “gradually strengthening conviction formed out of an early skepticism over more than two decades of accumulation of more and better data and personal study of this complex multidisciplinary science topic.”

Some said even debating the “if” of AGW was counterproductive because it’s such a settled issue and that time and energy must go toward the “how,” as in how to stop it.

If they absolutely had to name just one source, then it would have to be the IPCC, was the general consensus. Other sources members referred me to include

The SEJ’s own climate guide

Lester Machta research from the 1970s

Roger Revelle’s seminal 1982 paper

Charles Keeling’s work

The Millennium Ecosystem Assessment

And then there’s Coby Beck’s blog, A Few Things Ill Considered. In his How to Talk to a Climate Skeptic, Mr. Beck gathers the pertinent consensus science into one handy Web presentation, laying it out in simple terms (helped by the fact he is not a climate scientist; he’s a software developer who’s followed climate change as a passion since 2006.) This stuff is so good green-site heavyweight Grist has made it their official line.

So if the science is so clear, why are skeptics seemingly everywhere? The obvious answer is money (and politics. Is there a difference?). There’s much riding on the country’s and the world’s approach to the environment, economically speaking. Old-school energy providers stand to lose a lot. (I dealt with this topic in a post on 2008 article “The organization of denial.”)

But then there’s subtler reasons, like how believing in AGW might threaten a person’s ingrained beliefs, or how we might feel overwhelmed by climate change. As another SEJer put it, “What are the reasons skeptics have for doubting? One reason is the overwhelming enormity of the problem vs. a lone individual's inability to make a noticeable difference.”

I read something recently that speaks to this. It’s a comment from one Dan W., in response to a particularly comment-inducing post on FiveThirtyEight:

“The question is: how much do we really care? The answer is surely: we care relative to how much it will effect us and our children with a highly diminishing curve as the generations pass. Even at record avg lifespans humans don't live long enough to care, intrinsically, about what they do to the planet.”

And another reason – the one that explains my own occasional lags into AGW denial – is plain old wishy-washiness. I’m always questioning beliefs, even those that would seem fundamental, and can be swayed by sound (or sound-sounding) arguments. Ugh. I hate that about me. But I kind of like it too. It’s what gets me in trouble when I read an informed-sounding voice (see A1965bigdog’s comments) that seems to make a good argument against AGW. But it’s also what gets me out of it when I head back to the Coby Becks of the blogging universe. And to the James Hansens. And to our very own government.

Phew. I feel better. It’s all clear to me again. Of course AGW is real, and of course something needs to be done about it.

Now just keep me away from those comment sections.