Arctic temps are getting cooler … err … colder.

It’s a must see.

Do you debate the increasing ocean acidification too?

“WATER VAPOR TRENDS AND VARIABILITY FROM THE GLOBAL NVAP DATASET” by Thomas. H. Vonder Haar1, John M. Forsythe, Johnny Luo, David L. Randel and Shannon Woo

“Ocean water vapor and cloud burden trends derived from the topex microwave radiometer” by Brown, S.; Desai, S.; Keihm, S.; Ruf, C.

‘Trends in middle- and upper-level tropospheric humidity from NCEP reanalysis data’ by Garth Paltridge, Albert Arking and Michael Pook

And who the hell ever claimed there could be?

An Inquirer – water vapour feedback is observationally confirmed. See for example:

* Soden et al. 2002, Science, “Global Cooling After the Eruption of Mount Pinatubo: A Test of Climate Feedback by Water Vapor”
* Dessler et al. 2008, GRL, “Water-vapor climate feedback inferred from climate fluctuations, 2003-2008″
* Gettelman & Fu, 2007, J. Climate, “Observed and Simulated Upper-Tropospheric Water Vapor Feedback”

You didn’t specify which observations you think “run counter to the intuitive thought”. I wonder why not?

There are some phenomena which are well suited for laboratory experiments, and some which are not. Laboratory experiments require the ability to isolate the relevant variable, control the other variables, and implement procedures that are verifiable and repeatable. Think of the economic debate between supply-siders and Keynesians. Both point to the Kennedy tax cuts as proof of their positions with Keynesians maintaining that consumers increased demand with increased disposable income and supply-siders arguing that the tax cuts led to increased motivation, more capital, and better technology which lead to increased supply. We can’t isolate key variables and repeat the experiment. (The Reagan tax cuts and Bush tax cuts again led to economic growth, but again key variables are not isolated. Supply-siders argue that the surge in government spending in the late 60s & 70s did not seem have a similar impact on economic growth, but Keynesians argue that the variable of increased energy prices was not controlled.)
In climate issues, both sides agree that under laboratory conditions doubling CO2 from preindustrial levels would lead to a one degree increase in temperature and that the impact is logarithmic. (Perhaps, we would not be greatly concerned about a one degree increase; perhaps the natural variability is more.) However, there are issues that we cannot get into the laboratory experiment – water and air convections, cloud formations, flora response, and other feedbacks – to name just a few. Global warming pessimists accept that CO2-induced warmer temperatures will cause a positive feedback via increased water vapor in the air. That is an intuitive thought and would cause temperatures to rise by more than the one degree. However, that feedback is not replicated in the laboratory experiment, and there are some scientific observations that run counter to the intuitive thought. Moreover, laboratory experiments will not tell us whether a small rise in temperatures will have overall beneficial or harmful impacts. Increased crop production and lower mortality rates have been associated with higher CO2 levels and warmer past temperatures, but we could hypothesize all sorts of negative impacts from warmer temperatures, and maybe we do not need to hypothesize – think of the 1930s. Therefore the question about laboratory experiments is a good one, and one that neither side is afraid of, but not one that resolves the argument.