Tuesday, March 13, 2007

global warming swindle

I watched the great global warming swindle on C4 last night. Although biased in a totally different way than everyday news, it builds a strong case against the global warming hypocrisy. Its claims are:
  • the global warming movement is a platform for the left
  • global warming research attracts a lot of funding
  • the link between CO2 and global temperature is complex and causation is reverse
  • sunspots are more likely to cause warming
  • the IPCC is a governmental body censoring scientific opinion
  • the global warming agenda was initiated by Thatcher's desire to justify nuclear power
With which do you agree or disagree?

1 comment:

RobC said...

I watched this piece of anti-science propaganda camouflaged as a plea for scientific rigor, all 76 minutes of it. My estimate is that 70 minutes of it is nothing but political whining: some bizarre account of Mrs. Thatcher's suborning of scientists in order to break the coalminer's union and environmentalists' turning it into a political cause to enforce communist doctrines, all owing to a contemptuous hatred of all of mankind in general and of poor people in particular. Still, credit where credit is due: the film is slickly produced, with splendid graphics and music, and warmly confident experts assuring us it's all crap.

I can't say for sure how anyone could take all this seriously, but I'll offer the opinion that people find it much more interesting than global warming, which actually is pretty boring stuff.

The remaining 6 minutes or so that addressed the facts surrounding global warming were filled entirely with misinformation and irrelevancies, which may be summarized as follows:

1) Solar activity explains past changes in Earth's temperature.

No one challenges this notion. It's clear that when the CO2 level was lower and essentially constant, solar activity was the main driving force. That's changed since 1900. CO2 concentration is higher now, and it is changing rapidly. Now CO2 concentration is a bigger driver than solar activity.

2) Solar activity matches temperatures in the last 100 years better than CO2 concentrations, especially 1940-1970

This is plainly false. Solar activity clearly increased between 1940 and 1960. To justify this claim, the producer presents a sunspot plot that doesn't even resemble the data. He doesn't give a reference, so one can only speculate, but it appears that someone used a smoothing procedure on the data, and somehow made it appear that sunspots decreased between 1940 and 1960, even though the real data clearly show that they increased.

What happened between 1940 and 1980 is actually well-understood. Pollution during and after the war, when industrial activity was raised to unprecedented levels, caused temperatures to decline. Particulates and aerosols have a cooling effect by reflecting sunlight and by causing clouds to form. About 1970, serious efforts were started to control particulate emissions from fossil-burning power plants, and the temperature data clearly show that global warming accelerated.

Furthermore, and more importantly, solar activity peaked in 1980, but temperatures have continued to rise. The only factor that can explain this is greenhouse-gas concentration.

3) CO2 levels lag behind temperatures by 800 years or so.

First, this reading depends on proxy data, since records don't go back that far. But it could well be true because it's so consistent. If it is true, it's not good news. The proxy records show what you'd expect anyway: global warming causes greenhouse gases. Since greenhouse gases cause global warming (an inescapable fact of physics), we could face a compounding effect, where greenhouse-gas concentration and temperature reinforce each other all the way to the worst case. This is the possibility that causes the most concern.

With respect to global warming, however, all this is irrelevant to the question of whether or not artifical CO2 emissions are causing an increase in global average temperature.

4) Troposphere data don't reflect the same degree of heating as would be expected.

This is outdated, incorrect information. Here's a quotation from the Executive Summary of the Climate Change Science Program Synthesis and Analysis Product 1.1:

"Previously reported discrepancies between the amount of warming near the surface and higher in the atmosphere have been used to challenge the reliability of climate models and the reality of humaninduced global warming. Specifically, surface data showed substantial global-average warming, while early versions of satellite and radiosonde data showed little or no warming above the surface. This significant discrepancy no longer exists because errors in the satellite and radiosonde data have been identified and corrected. New data sets have also been developed that do not show such discrepancies."

5) Artificial emissions aren't sufficient to explain the increase in CO2 concentrations. Natural emissions are greater.

This is plainly false. According to the International Energy Agency's "Key World Energy Statistics", 26,883 million tons of CO2 are emitted from artificial sources per year. That is 0.87% of the amount of CO2 in the atmosphere, the concentration of which is rising roughly 0.5%/year. So, if 60% of the emitted CO2 stays in the atmosphere, it explains all of the increase. But it's true that other greenhouse gases are contributing as well.

I've noticed a willingness of people to accept this argument without any reservation, even people who brag about how naturally skeptical they are. Perhaps the reason is that the subject usually is discussed in bits and pieces, so people don't have a reference point from which to consider misinformation. I've put together a coherent exposition of the facts on a web page called Global Warming: A Guide for the Perplexed.