Blarney: Dave, why so serious?
Dave: I just can’t believe the stupidity of some people.
Blarney: To whom do you refer?
Blarney: What is stupid about that?
Dave: Do you know what the largest greenhouse gas is?
Blarney: Sure. Everybody knows that it is Carbon Dioxide. That’s what is causing Global Warming – I mean – Climate Change.
Dave: Actually, Blarney, the largest greenhouse gas is water vapor. It makes up about 4% of the atmosphere. Carbon dioxide makes up about four hundredths of one percent.
Blarney: But, I heard that the concentration of carbon dioxide went up dramatically over the last thirty years.
Dave: Well, it has increased over 35% in the last 300 years. That means it went from 275 parts per million (ppm) to 375 ppm.
Blarney: You’re saying that it increased only 100 ppm in 300 years? The concentration went from 0.000275 to 0.000375? And that caused all this warming?
Dave: Actually, the globe has been cooling since about 1998, even though the atmospheric carbon dioxide continued to increase.
Blarney: Why would that be?
Dave: Well, it wouldn’t IF carbon dioxide caused warming. That’s one of my points.
Blarney: ONE of your points?
Dave: Yes. You do know that there was a big Ice Age, right?
Blarney: Yes, that first one was the best of the three.
Dave: Not the movie, Blarney.
Blarney: Oh. OK. Yes there was an ice Age.
Dave: And you know that there was a little ice age?
Blarney: Yes, around 1550 to 1850. But there were warming periods in there.
Dave: You get a gold star, Blarney. Now tell me what caused those warming periods or for that matter, what ended the big Ice Age?
Blarney: Well… I don’t know. I never thought about it.
Dave: And you know that there were concerns about a new ice age in the 1970s?
Blarney: Yes, but it warmed up instead. That was caused by Anthropogenic Global Warming. The science is settled.
Dave: Why do I bother?