weight of air

[Peachtree]

I am re-submitting the question because of typo error in the original. How heavy would a column of air weigh if it was 1" square & 600 miles high?

[bob_builder]

Normal atmosphere is 1 kilogram per square centimeter (14.7 pounds per square inch) but thats for less than 600 miles I'm sure

[brachiopod]

This is an awkward one.

The weight (mass) of a column of air would be a function of its density and volume.

However, the density of air at the bottom of the column is a lot greater than that at the top of the column, since the 'weight' of the air above it compresses it, making it more dense.

Moreover, the boundary of the Earth's atmosphere and space in generally considered to be about 100km (62 miles), so your 'column' of air at 600 miles is almost 10 times this height. That implies that nearly 90% of your air would be in space, and would therefore have no gravity to 'keep it in a column', and no pressure to give it any significant density and to prevent its dispersal.

You'll need to be able to do calculus to work this one out, even for a column of air, say, 60 miles high, as the air at the very top will have a density tending to zero, whilst the air at the bottom (say, sea level) would be around 1.25 - 1.29 kg/m^3 - and will vary between these for every change in altitude, and that variance is non-linear ( so that means that you can't say "for every increase of X in altitude, density decreases by Y ".)

For obvious reasons, I have ignored the absolute humidity of the air, and its temperature - as these factors will also have an effect on the density.

[Calvesy]

At the risk of breaking with form here and actually answering your question, the answer is 15 pounds.

You wouldn't be able to weigh it because it is neutrally buoyant, but we feel it as pressure, 15 psi.