- We ask Bryson what could be making the key difference:
- Q: Could you rank the things that have the most significant impact and where would you put carbon dioxide on the list?
- A: Well let me give you one fact first. In the first 30 feet of the atmosphere, on the average, outward radiation from the Earth, which is what CO2 is supposed to affect, how much [of the reflected energy] is absorbed by water vapor? In the first 30 feet, 80 percent, okay?
- Q: Eighty percent of the heat radiated back from the surface is absorbed in the first 30 feet by water vapor…
- A: And how much is absorbed by carbon dioxide? Eight hundredths of one percent. One one-thousandth as important as water vapor. You can go outside and spit and have the same effect as doubling carbon dioxide.
update: short post here, but a wonderful series of comments to follow on the news that Neptune has now joined Mars in warming at the same time as good old Terra: perhaps it is the sun??