- Water vapor makes up 95% of all greenhouse gases
- I couldn't find anything that substantiated that high of a percentage. Actually, I found several websites that said up to 98%, but those sites would be deemed "crackpot, right-wing, deniers" websites, so I won't count those. Wikipedia's greenhouse gas page puts the number between 66% and 85%. The National Oceanic and Atmospheric Administration does not give a percentage, but does say that water vapor is the most abundant greenhouse gas. So I think it is safe to say that there is unanimous agreement it is the most abundant greenhouse gas.
- Many sites like the Wikipedia page and others (Slate.com, Encarta) talk about greenhouse effect, not the overall percentage of the gas. This has merit since the different gases have more or less ability to trap heat and radiation, I get that. What I don't get is how they come up with the numbers. Most sites say water vapor is responsible for 60-70% of the greenhouse effect. It appears that they come up with an "effect" number based on climate models. I personally am extremely wary of any climate models, simply because they are just that, models. They are only as good as the data you put into them, and in my experience I have seen enough mistakes to put very little stock in them.
- Only 3.2% of all CO2 is man-made.
- I'll be honest, this one was a little harder to verify. It took me a good 20 mins on Google to find even one article discussing this. Its also mentioned in a few of the other previous articles and as far as I can tell, this number seems to be accurate.
- Man-made CO2 contributes only 0.117% of the relative greenhouse influence.
- This I'm not quite certain about either. Not looking at this "effect" or influence number, the number provided is somewhat close. If CO2 only makes up less than 5% of total greenhouse gases and man only creates 3.2% of the total CO2 produced, then my math (1.0 * 5% * 3.2%) = 0.16%. That constitutes how much man made CO2 there is in relational to all the other greenhouse gases. However, I've seen websites that suggest CO2 makes up as much as 30%. Even in that case the actual percentage then of man-made CO2 to total greenhouse gas pollutants only jumps to 0.96%.
What makes this whole discussion so difficult is that nearly every government study neglects water vapor from all their calculations. So naturally the CO2 effect looks an order of magnitude larger. For instance, the EPA says that the largest source of CO2 emissions globally is the combustion of fossil fuels. But if man only produces 3.2% of CO2 that statement is patently false.
There is also no doubt (as evidenced by the EPA website) that numbers are being used to sway perception. One that kept showing up on all the pages I was looking at was the amount of CO2 in the atmosphere. You can see a table on the Wikipedia page. Its presented in such a way that it appears drastic in that over the past 200 years the amount of CO2 in the atmosphere has doubled. Okay, but that does not imply anything other than that its doubled. If the numbers begin small and are relatively insignificant, then who cares if the numbers double? I'm not implying that the amount of CO2 in the atmosphere before, or now, is insignificant. All I'm saying is that without any context they use those numbers to scare people into thinking that doubling the CO2 in the atmosphere is a major problem. If I make a $100k/yr in salary and my income tax goes from $100/yr to $200/yr I'm not too worried. But if my income tax doubles from $25k/yr to $50k/yr, now I'm worried. All that to say, numbers need to seen in a bigger context before they meaning anything.
And the last thing this little exercise taught me is that it is nearly impossible to get any real facts for government or research facilities on these topics... from a Google search. Everything seems shrouded in confusing and misleading statements and facts.
