Atmospheric pressure at high altitude

Nereid

Besides, weather maps - the ones with isobars that is - would look really, really ugly if they showed the actual pressure. I mean, how could any Californian make sense of such a map???

Andre

Moreover, the aviation standards require sea-level-corrected air pressure to calibrate the good old barometric altimeters. Although it seems nice to see zero altitude when departing from Mexico city but that would lead to big surprises when landing on LA or Colorado Springs

tumor

What would be the atmospheric pressure in Kg on 1cm square?

russ_watters

That's a strange choice of units, but about 1.0.

Bystander

"kg/cm² strange?" Check gauges on whatever regulators are handy --- output side usually includes this rather peculiar "metric engineering unit."

GRQC

Actually, measuring density in mass/area isn't that uncommon, especially in radiation and particle physics. Usually this is referred to as "mass thickness", and e.g. with radiation shielding is a method of determining the amount of matter needed to attenuate gamma rays (independent of the density of the specific material, be it lead, iron, wood, etc...).

It frequently comes up in particle physics in any atmospheric experiments, e.g. cosmic ray showers and/or atmospheric neutrino expts.

Dimus

I'd ask the same question from the tech point: at what temperature water boils in Mexico city?

Bob S

Here is code I use. It gives pressure = 78,500 Pascals at 2000 meters.
REM ===============================
Rzero=6378100 ! Earth radius in meters
R=Rzero
g=9.81
Pzero=100760 ! pressure in Pascals at sea level
P=Pzero
Dzero=1.28 !Density of air at 0 deg C, kilograms per cubic meter
D=Dzero
dR=+1 ! going up 1 meter
DO
D=Dzero*P/Pzero ! ideal gas, const temperature
R=R+dR
g=9.81*(Rzero/R)^2
P=P-dR*D*g
LOOP while R<Rzero+2000
PRINT R,P,D
REM ====================================