Taranto Part II

The other day, the Wall Street Journal's James Taranto (pictured left) cited a blogger who did a google search to make his case that atmospheric CO₂ is insignificant when it comes to a planet's temperature. After somebody pointed out a rather serious flaw in this argument, James Taranto defended his position by citing a NASA website for children.

But even this misses the point. In addition to being way less dense per unit volume than earth's atmosphere, the Martian atmosphere is also far smaller in volume (Mars is about 1/2 the size of earth).

Taranto also fails to mention that the Martian atmosphere contains very little water vapor, which is a far more significant greenhouse gas and which (through a feedback mechanism) more than doubles the amount of warming caused by CO₂ in our atmosphere.

Mars is also 1.5 times as far away from the sun as we are.

All of this taken together severely undermines Taranto's original point, which was that:

"As blogger George Reisman notes, the atmosphere on Mars is 95% carbon dioxide, just shy of Venus's 96%. (The Earth's atmosphere, by contrast, is less than 0.04% CO2.) Average temperature on Mars? Eighty-one below zero."

Keep in mind that all of this was spelled out to make the case that Al Gore is prone to exaggeration and plays loose with the facts.