Tuesday, June 30, 2009

Climate Change expectations getting more realistic

I can't tell you how happy this makes me.
The new projections, published this month in the American Meteorological Society's Journal of Climate, indicate a median probability of surface warming of 5.2 degrees Celsius by 2100, with a 90% probability range of 3.5 to 7.4 degrees. This can be compared to a median projected increase in the 2003 study of just 2.4 degrees. The difference is caused by several factors rather than any single big change. Among these are improved economic modeling and newer economic data showing less chance of low emissions than had been projected in the earlier scenarios. Other changes include accounting for the past masking of underlying warming by the cooling induced by 20th century volcanoes, and for emissions of soot, which can add to the warming effect. In addition, measurements of deep ocean temperature rises, which enable estimates of how fast heat and carbon dioxide are removed from the atmosphere and transferred to the ocean depths, imply lower transfer rates than previously estimated.

Yeah. The estimate's more than doubled in 6 years because the model's have all changed. Or is it that scientists who present these inconvenient truths no longer fear getting shot in the face by Richard Bruce Cheney? If it's actually model improvement, and model improvement causes a doubling rate of five years, we're pretty much toast. The mean July high for New York City is 83 °F. Adding 5.2 °C would give us the same mean July high as Miami.

Professor Krugman yesterday pointed out some issues
[T]he House passed the Waxman-Markey climate-change bill... [b]ut if you watched the debate on Friday, you didn’t see people who’ve thought hard about a crucial issue, and are trying to do the right thing. What you saw, instead, were people who show no sign of being interested in the truth.... [T]o believe that global warming is a hoax you have to believe in a vast cabal consisting of thousands of scientists — a cabal so powerful that it has managed to create false records on everything from global temperatures to Arctic sea ice.

We can start to have some hope around Climate Change science affecting policy, although I still don't think there's a big chance Congress will meet my goal of ceasing electrical production with greenhose gas emissions by July 17 of 2018.

I'm sort of hoping that if we do start to take our imminent demise seriously, we can still avoid war with China.


nephos said...

The fact that projections are diverging rather than converging with time seems like an indication that everything is still off in la-la land. Adding more bells and whistles to a model doesn't make it more right necessarily, but only more free to get things wrong.

And these societal models are all bunk anyway until they can do something more sensible than extrapolate based on past trends. When they can predict an economic crash a la Malechem, then I'll start to believe 5 degrees by 2100.

Anonymous said...

Great trend modeling coming at XKCD today, by the way.