Ask anybody for the percentage of Carbon Dioxide (CO2) in the atmosphere, and you will likely get an answer that’s off by a factor of a thousand. That’s a little shocking in a world where virtually every conversation eventually turns to CO2-driven climate change. Why is the scientific community not diving into the breach to fix this widespread misconception about our home atmosphere? Because climate scientists have worked hard over the last 20 years to encourage you to forget this fact that most people learned in high school: that CO2 is a trace element in Earth’s atmosphere. It barely exists at all, amounting to no more than 0.03768% of total gases, as illustrated in the diagram at right.
In contrast, the atmosphere of Venus, the planet that caused the debate on “greenhouse gases,” is almost 97% CO2. The only way climate scientists can convince you that the Earth is on the verge of heating up like Venus is to first help you forget the fact that the two atmospheres are factually nothing alike. The bad news is, they’ve succeeded.
Ryan Scott Welch writes (as quoted by Anthony Watts):
[W]hen questioned about how much CO2 is in our atmosphere most people give me a guess of somewhere between 30% and 70%. When I tell them that CO2 is only 0.04% or really about 395 ppm (parts per million) they generally look at me as if I was speaking some kind of foreign language. The layman simply cannot convert 0.04% of the atmosphere or 395 ppm into anything they can picture or relate to. In searching for some way to help the layman to understand the earth’s atmosphere, CO2, and the human contribution to atmospheric CO2, I came upon the idea of relating a sample of the atmosphere to something that nearly every person has seen, a football stadium.
Ryan goes on to explain that if the entire Earth atmosphere was represented by the 100,000 seat Dallas Cowboys Stadium, only 40 of those seats would be CO2. Also, less than half of one of those seats could be attributed to human causes. On top of that, there’s evidence that the proportion of CO2 in the atmosphere has been considerably higher in the past. Some have even proposed that the current levels are so small that plant life on the planet is literally suffocating, and represents only a shadow of the growth in past millenia.
Given all that, is it any surprise that climate scientists, whose funding depends on keeping alive a little hysteria, are in no hurry to correct this massive public misperception about CO2? Try the trivia test for yourself. The next time a co-worker or your own child talks to you about climate change, ask them the question about the percentage of CO2. See what they say. I have been unable to find any formal polling results that quantify public ignorance on this question. It may be too technical for them to poll. But my own experience supports Welch’s contention. Most people I know believe it’s at least 10%. So, ask the question. When you tell them it’s only 0.04%, you might have a shot at opening their minds on the issue. The fact that CO2 is a trace gas doesn’t prove or disprove anything, but it does establish the basis for a little healthy skepticism.