Monday, May 12, 2008

Climate Change

NASA's foremost climate scientist, Jim Hansen (you may remember the Bushies trying to muzzle him), has a new paper on arxiv.org. Here's the abstract:

Paleoclimate data show that climate sensitivity is ~3 deg-C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6 deg-C for doubled CO2 for the range of climate states between glacial conditions and ice-free Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425 +/- 75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects.
Emphasis added by me. Holy shit, people. The cliff's ahead, and we're blithely driving toward it.

Are you biking to work yet?

5 comments:

Whitney said...

"Are you biking to work yet?"

every other day. and, i don't have to commute to an out-of-town TA anymore, thank god.

what some people seem to miss about this is that it doesn't matter if the change is anthropogenic or not (folks get defensive). if it's going to fuck up our way of life, it's something we should take seriously, regardless of WHO started it.

trogon said...

We're OVER the cliff. We're in Wile E. Coyote not-looking-down mode.

Granted, my "cliff" is "say goodbye to polar bears and penguins and hello to deserts in Kansas", not "Venusian runaway", but still.

And no, I'm not biking to work, but I'm carpooling with six other people -- do I get partial credit?

Brian said...

I should get extra credit! I'm moving my family to a town we're iffy about living in just so I don't have to commute to work anymore. (Ok, it's not all for the sake of the planet, I'm sick of paying for gas and wasting an hour every day too.)

Fish said...

Well, J. and I bike in every day. Yay! It's awesomely sweet, and wife draws jealous/envious looks from her workers who drive SUVs from 20 miles away.

$200 per week for the gas, so I hear...

Anonymous said...

Phase out coal power? Good luck! Replace it with nuclear power and you stand a chance. Not only will you decrease CO2 emissions, but less people will die from mining accidents, air pollution, and carcinogens released into the environment. Agitate instead for solar and wind power, and the coal industry will be laughing (see Denmark).

Kill the American love affair with the car? No way. That is not going to happen without force. You'll have to redesign your cities on a European model. You'll have to actually believe in the role of government to do good, rather than progressively destroy it as you have eagerly done over the past couple of decades. Better though for the evil empire to collapse and start from scratch as at least a dozen seperate nations.

Oh yeah, residential energy use by Americans corresponds to roughly 4% of world energy use. Cut your residential use by 50% (good luck with that!) and you'll have a 2% effect on CO2 emissions. Which is less than the 3% that it's currently growing at anyway. But at least solar panels and biking will salve your precious consciences.