One rule of opinion writing is that you don't warp the position you oppose, then beat up on a straw man. One, it's unfair. Two, it leaves readers less well informed, not better.

Which is why Jack Kelly's truly bizarre column headlined "Globull Warming," in the Sunday Post-Gazette, is as irresponsible as it is comically easy to rip apart.

Kelly, the P-G's resident right-wing hatchet man, begins by citing a recent interview between Eve Ensler and CNN's Joy Behar in which Vagina Monologues playwright Ensler appears to blame climate change for tsunamis and earthquakes.

The bigger question is, Why should the opinions expressed by a playwright on a chat show even come into play? Why doesn't Kelly take on, say, NASA, whose data unequivocally shows that the planet is warming?

Kelly's other sources include "Minnesota blogger John Hinderaker" (who Kelly tells us gets some of his information about moose populations from "recent news accounts") and Kelly's fellow right-wing pundit Jonah Goldberg. (Kelly does cite two researchers, on the matter of polar-bear populations and the prevalence of malaria, but neither of them addresses the issue of whether the earth is growing warmer.)

The closest Kelly gets to accurately stating the case he's attempting to refute is to quote "journalists" who tell us that "climate isn't weather." Well, those journalists are right -- it's not. And scientists, of course, say the same thing. When I interviewed University of Pittsburgh climatologist Mike Rosenmeier for a recent piece about misperceptions of climate change, the first thing he emphasized was that climate is not weather. (Climate is basically average weather over time, over a large geographic area.)

Then Kelly excoriates those same unnamed journalists as the very people who for years told us that every "hot weather event" was proof of climate change.

Of course, lots of people, including some careless journalists, made cracks about global warming during heat waves. And of course they were wrong -- just like Eve Ensler is wrong about tsunamis ... and just like the people making Al Gore jokes when it snows in Washington are wrong that such weather disproves climate change now.

Snowfall in Washington, by the way, is entirely consistent with a warming planet. Here's why. Snow requires two things: temperatures below freezing and moisture. The world, which is large and complex both atmospherically and hydrologically, is warming on average, but relatively slowly and fitfully, rather than at a steady, rapid pace planet-wide. So it's still going to get below freezing sometimes. And a warmer planet means more moisture in the air. Thus, snow.

This is junior-high science stuff. Kelly and other climate-change deniers play on the fears and prejudices of people who imagine that somebody (maybe even nefarious "journalists") told them that global warming meant that winter was going to vanish immediately. (On that matter, Kelly's column also misquotes Robert F. Kennedy, claiming that in a 2008 column Kennedy asserted it would never snow again in Washington, D.C. Kennedy made no such claim.)

For context's sake, it's also worth noting that, according to NASA, the 20 warmest years on record have occurred since 1981, with 10 of the warmest years coming in the past 12 years alone. So apparently, although Kelly and his fellow deniers don't view such long-term global evidence as evidence for climate change, one snowy winter east of the Mississippi is evidence against.

Some "deniers" are determined never to accept that climate change is real. But those of us who acknowledge its reality bear some responsibility, too, for not explaining the phenomenon better.

For too long, we've talked about climate change in terms of "belief," i.e., "Jack Kelly doesn't believe in climate change." But the only belief that's necessary involves the evidence found by eyes focused on rising thermometers, and on the melting Greenland ice sheet; the growing deserts in Africa and China; the disappearing glaciers in Alaska, the Rockies, the Andes and the Himalayas; and in the Arctic Ocean, where some predictions say summer sea ice -- a phenomenon thousands of years old -- could be gone in just a few years.