what is the relationship between air pressure and altitude?

Question

what is the relationship between air pressure and altitude?explain how a US weather Bureau map of air pressure deals with this relationship.

Answer 1

I think pressure decreases with altitude.

Answer 2

Complicated. If the temperature of the air were uniform, the pressure would decrease logarithmically with altitude. But it isn't -- it decreases by about 2 C per thousand feet increase in altitude. If you grind out the mathematics (it's a fairly easy integral calculus problem), you find that the pressure decreases at something like the -4.25 power of the altitude. This is good up to a bit over 30,000 feet; at that point, you're in the stratosphere and the temperature becomes nearly constant with increasing altitude, so the pressure decline is logarithmic. The pressure is about half of sea level pressure at 18,000 feet, and a quarter at 41,000 feet. You can find tables and graphs of this in:

Answer 3

In one common usage, the two terms would mean the same thing. The atmospheric pressure usually just means the pressure of the air in the atmosphere (like when they talk about low-pressure systems in the weather), and that could also be called "air pressure". But I can think of two other usages that could make the terms mean something different.

The first is that "atmospheric pressure" is sometimes used to designate a specific pressure, namely the pressure of the atmosphere at standard sea level conditions. This standard pressure of "one atmosphere" is defined as exactly 101,325 Pascals (to use the SI [Metric] unit of pressure), which in traditional English units comes out to about 14.696 pounds per square inch (psi). So, on a given day depending on the weather, the atmospheric pressure or air pressure might be something like 0.98 atmospheres (though in the weather business it is usually expressed in other units like millibars or millimeters of mercury or inches of mercury). In the part of Colorado where I live, the atmospheric pressure is more like 0.85 atmospheres because of the altitude.

The second different usage is probably actually what you had in mind. Sometimes we use "air pressure" to refer to the amount of air that is pumped into an inflatable object like a tire or a basketball. The more correct name for that usage is "gauge pressure." Gauge pressure is the *difference* between the pressure of the air inside the inflatable object and that outside the object (which would be atmospheric pressure). So, if your pressure gauge says you have 50 psi pressure in your bicycle tire, and the atmospheric pressure is 14 psi, that means that the total pressure inside the tire is actually 64 psi. But it is common to not worry about the total pressure and just use the gauge pressure (because that is easier to measure), and say that the "air pressure" is 50 psi

Answer 4

Air rigidity decreases with altitude from an standard of approximately 1013hPa on the exterior to 0hPa in area - which isn't that some distance up. Temperature decreases with altitude interior the troposphere, will enhance interior the stratosphere. decreases interior the mesosphere and will enhance interior the thermosphere till the molecules are so some distance aside on the edge of area that temperature will become immeasurable.

Answer 5

air pressure decreases when the altitude is increases.
no clear idea how they do it, but they probably use devices that use this principal.

Answer 6

Opposite.

The higher the lower.
The lower the higher.

Answer 7

inverse?