Altitude Compensation

[Chuck Tomlinson]

Mark Pitts wrote:
>
>But seriously... I agree oil and vinegar make salad dressing, but it does
need to be shaken to get the relevant flavour, and if you dont shake the
atmosphere, it tends to separate. Not a lot, but it does, and the light
fractions float.

Near the ground, the atmosphere *is* shaken (and stirred) by convection
currents.  The fact that air temp near the surface (<20,000') decreases with
increasing altitude *guarantees* constant convective mixing. Convection
mixes the air vertically, and winds mix the air horizontally.

Up above 60,000' there are layers of the atmosphere that do not have a
significant vertical temperature gradient.  Convective mixing is minimal
there, but my car won't run at that altitude :-)

Where we live and drive, the mole fraction of oxygen in air is constant at
about 21%.

--
Chuck Tomlinson