"Completely wrong." "Simply ignorant." "Scientifically incorrect." "Utter Nonsense." "Very odd." These are words scientists have used in the past to describe the nationally televised ramblings of weather forecaster Joe Bastardi, who Fox News hosts from time to time in an apparent effort to dismantle whatever its viewers might know about physics.
When we last saw Joe, he was breaking the news that the world's climate scientists had overlooked the first law of thermodynamics. (He was wrong.) After a thorough round of mockery in the blogosphere, we thought surely Fox would throw away Bastardi's phone number. But here he is on Fox Business this morning, declaring that carbon dioxide "literally cannot cause global warming":
BASTARDI: CO2 cannot cause global warming. I'll tell you why. It doesn't mix well with the atmosphere, for one. For two, its specific gravity is 1 1/2 times that of the rest of the atmosphere. It heats and cools much quicker. Its radiative processes are much different. So it cannot -- it literally cannot cause global warming.
Asked about Bastardi's statements, Kerry Emanuel of MIT said: "Utter rubbish. Sorry to be so direct, but that is just the case." NASA climatologist Gavin Schmidt added: "Bastardi is attempting to throw out 150 years of physics." "He seems very confused," said physicist Richard Muller.
Bastardi may be hoping that when delivered confidently, terms like "specific gravity" and "radiative processes" can convince Fox's viewers that he knows what he's talking about. But don't be fooled; he is again garbling the very basics of climate science. Schmidt explained:
Bastardi doesn't understand the first thing about the greenhouse effect - it has absolutely nothing to do with the 'specific gravity' of CO2 or any other greenhouse gas, it has to do with the fact that GHGs absorb and radiate infra-red heat and in doing so warm the surface of the Earth.
If it weren't for the natural greenhouse effect, we wouldn't even be here to argue about climate change -- it keeps the planet warm enough for life to thrive. Greenhouse gases trap heat that would otherwise escape to space and leave behind a big cold rock like Mars. While water vapor is the greenhouse gas that contributes the most to the natural greenhouse effect, CO2 drives the recent changes to Earth's energy balance and temperature. As we substantially increase the concentration of CO2 in the atmosphere, the greenhouse effect is enhanced, causing warming. The rise in temperatures sets off several feedback processes, including increased water vapor, that boost the warming further.
According to Bastardi, because CO2 is heavier than other gases in the air, it isn't well-mixed through the atmosphere and can't cause warming. In fact, we know CO2 is well-mixed because scientists measure it from different locations. Muller said CO2 is "completely mixed in the troposphere by turbulence," adding, "I think he may be confusing CO2 with water vapor, which (because it freezes out) does not mix well." The ability of CO2 to absorb and radiate heat was observed over 150 years ago and has repeatedly been measured since.
Bastardi went on to claim that "the entire globe has cooled quite a bit." You be the judge: