Freeze! [or] Panic!...

Even in this time of starkly divergent and entrenched positions in public debate do you simultaneously run across two well-reasoned arguments that both appeal and completely contradict.

First, this truly depressing information about the new urgency in reducing carbon emissions, since a 2℃ rise (the popular target maximum) will be much worse than we had previously calculated.

The thing is, if 2 degrees C is extremely dangerous, 4 degrees C is absolutely catastrophic. In fact, according to the latest science, says Anderson, "a 4 degrees C future is incompatible with an organized global community, is likely to be beyond 'adaptation', is devastating to the majority of ecosystems, and has a high probability of not being stable."
Yeeeah. You'll want to read that sentence again. Then you'll probably want to pour yourself a stiff drink.
Obviously, "incompatible with an organized global community" is what jumps out, but the last bit, "high probability of not being stable," is equally if not more important. One of the most uncertain areas of climate science today has to do with feedbacks -- processes caused by climate change that in turn accelerate (or decelerate) climate change. For instance, heat can melt the Arctic permafrost, which releases methane, which accelerates climate change, which melts more permafrost, etc.
Based on current scientific understanding, positive climate feedbacks -- the ones that accelerate the process -- considerably outweigh negative feedbacks. At some level of temperature rise, some of those positive feedbacks are likely to become self-reinforcing and effectively unstoppable, no matter how much emissions are cut. These are the "tipping points" you hear so much about.
But at what level? Will hitting 2 degrees C trigger runaway positive feedbacks? It's difficult to know; this is one of the most uncertain areas of climate science. James Hansen thinks 2 degrees C will do it. Others disagree.
But the situation becomes considerably clearer around 4 degrees C. At that level, there's good reason to believe that some positive feedbacks will become self-reinforcing. In other words, 4 degrees C would very likely be a way station on the road to much higher temperatures. [More]

There is an excellent presentation of the paper supporting this stance here. Not a lot of laughs. But it does mesh well with other research about the consequences of even small temperature increases on what we view as "normal" climate.

But the real stunner was this economic perspective from a econoblogger rising in the ranks, Karl Smith.

I hold these positions

1. Climate Change is almost certainly real
2. Humans are almost certainly causing it with carbon emissions, deforestation and domestication of animals
3. There will be large environmental costs associated with climate change include a very rapid increase in extinctions
4. There are likely to be major population dislocations because of climate change
5. There are likely to be major agricultural shifts because of climate change.

Nonetheless, we should pursue the development of fossil fuels as rapidly as possible including looking for ways to streamline regulation in North American regarding fossil fuel production. [More]

Smith goes on the the argument that since we can't reach emissions goals without deep economic sacrifice, we have to bet the globe on advancing technology fast enough to enable a solution to be found in the future.

This strikes me as a pretty gutsy position, but his case has merits. However, as the research like the first case continues, if it shows even worse outcomes than we are imagining now from temperature rises, the tradeoff suggested by Smith becomes an ever worsening gamble. He could still be right that since we don't show any interest in taking the threat seriously yet, at least in the US, betting on a future miracle may be our default non-decision.

But the odd and consequences of being wrong approach catastrophic.

On a slightly related note, I think Huntsman may be feeling some love from anybody-but-Mitt Republican voters and bigwigs, as he suddenly decided to backtrack on his courageous climate-change stand.

Jon Huntsman used to believe climate change is real. Now he’s not so sure.
In a move that’s sure to endear him to the conservatives who are starting to warm up to the former Utah governor, Huntsman said Tuesday under questioning from TPM that he now believes there’s “more debate yet to play out” before we can be sure climate change is really happening.
That’s certainly not the way Huntsman sounded waaay back in August, when he famously tweeted:

“To be clear, I believe in evolution and trust scientists on global warming. Call me crazy.”

That was part of an organized effort by Huntsman to be the sane one when it came to climate science. In an interview with Time, he said it this way:

“I’m not a meteorologist. All I know is 90 percent of the scientists say climate change is occurring. If 90 percent of the oncological community said something was causing cancer we’d listen to them.” [More]

Seems like a lot of folks are betting on a) a Gingrich implosion, and 2) a Romney closure failure. And I suppose climate change is an easy issue to play fast and loose with on the right. Ron Paul may be cornering the market in consistency and principle.