Yeah, I know… that doesn’t sound like a Technology article. But I got to thinking about how important it is that companies like Apple are striving to becoming energy and CO2 neutral. So I resorted to some arithmetic…
In April 2019 CO2 accounted for 413 millionths of our atmosphere — about 0.0413% of the atmosphere by volume. It’s a little bit higher now.
But “by weight” is different than “by volume”. CO2 is heavy compared to, say, Nitrogen (which is around 78% of the atmosphere).
Fortunately, if the molar weight of both Air and CO2 are known (and they are), there’s an easy way to figure out how much of air’s weight is due to CO2:
0.0413 V% x molar mass of CO2 / molar mass of air = 0.0413 x 44.0095 / 28.97 = 0.06274% of the atmosphere is CO2 (by weight).
Doesn’t seem like that should be a problem, right? It’s not even 1% of the total weight. It’s just 6.274 one-hundredths of a percent of the air by weight!
Well… if you draw a 1” square on your floor, the air above it weighs about 14.7 pounds. That’s called “One Atmosphere” of pressure. Out of that 14.7 pounds, CO2 will be 0.06274% of 14.7 = just 0.0092285 pounds.
I’m almost convinced! For sure there’s no problem! That’s less than 1/100th of a pound!
Except… a square mile is 5280 x 5280 feet, or 63,360” x 63,360” = 4,014,489,600 square inches. So the air above a square mile of the earth will contain 4,014,489,600 x 0.00922285 pounds of CO2. That’s 37,025,035 pounds.
Okay, so maybe we have a problem after all.
37,025,035 pounds is a lot. It’s 18,512 tons. Or 16,794,273 kg.
You see, this is the problem with climate change and a lot of other things in life: us humans are not really good at understanding really small things or really big things. Time, weight, money, atoms, the distance to the next nearest star, how rich Bezos is… all inherent mysteries to our puny brains.
The amount of CO2 in the atmosphere is a problem. A big problem. And it’s still getting worse every year.
But look on the bright side: you can now understand that trees really do come from air. They’re mostly carbon that they’ve absorbed through photosynthesis, water and the CO2 in the air that surrounds us all.
Probably we could use more trees.