Is anything clear about sea ice and global warming?

In an article in The New York Times by Andrew Revkin entitled "Scientists Report Severe Retreat of Arctic Ice" a scientist claimed that is was "clear" that global warming was affecting polar sea ice:

Mark Serreze, a senior researcher at the snow and ice center, said it was increasingly clear that climate change from the buildup of greenhouse gases was playing a role in the Arctic warming, which is seen not only in the floating ice but also in melting terrestrial ice sheets, thawing tundra and warming seawater.

"We understand the physics behind what's going on," Dr. Serreze said. "You can always find some aspect of natural variability that can explain some things. But now it seems patterns that used to help you don't help as much anymore, and the ones that hurt you hurt you more."

"You can't dismiss this as natural variability," he said. "We're starting to see the system respond to global warming."

Hmmm... if it is supposedly so "clear", why would The Times feel the need to add a caveat:

Still, he and other scientists acknowledged that both poles were extraordinarily complicated systems of ice, water and land, and that the mix of human and natural influences was not easy to clarify.

I do not doubt for one moment that quite a number of scientists are convinced that global warming from carbon dioxide generated by human activities is a cause of such melting phenomenon, but I do not believe that they as yet have an airtight case.

The Times than deepens their caveat by telling us that:

Sea ice around Antarctica has seen unusual winter expansions recently, and this week is near a record high.

Go ahead and try to blame that "expansion" of polar ice on global warming.

Who knows, maybe someday scientists really will have a solid case against carbon dioxide generated by human activities as the primary and predominate cause of global warming and climate change, but they certainly aren't there yet.

-- Jack Krupansky