Search results
Results from the WOW.Com Content Network
The earth atmosphere's scale height is about 8.5 km, as can be confirmed from this diagram of air pressure p by altitude h: At an altitude of 0, 8.5, and 17 km, the pressure is about 1000, 370, and 140 hPa, respectively.
Air pressure actually decreases exponentially with altitude, for altitudes up to around 70 km (43 mi; 230,000 ft), dropping by half every 5.6 km (18,000 ft), or by a factor of 1/e ≈ 0.368 every 7.64 km (25,100 ft), which is called the scale height. However, the atmosphere is more accurately modeled with a customized equation for each layer ...
For an isothermal atmosphere, or about 63% of the total mass of the atmosphere exists between the planet's surface and one scale height. (The total air mass below a certain altitude is calculated by integrating over the density function.)
In this formulation, R * is the gas constant, and the term R * T/Mg gives the scale height (approximately equal to 8.4 km for the troposphere). (For exact results, it should be remembered that atmospheres containing water do not behave as an ideal gas. See real gas or perfect gas or gas for further understanding.)
This latter equation can be solved over a single layer of the atmosphere. Since the atmosphere at a height of approximately 5.5 kilometres (3.4 mi) is mostly divergence-free, the barotropic model best approximates the state of the atmosphere at a geopotential height corresponding to that altitude, which corresponds to the atmosphere's 500 mb ...
The height at which the atmospheric pressure declines by a factor of e (an irrational number equal to 2.71828) is called the scale height (H). For an atmosphere of uniform temperature, the scale height is proportional to the atmospheric temperature and is inversely proportional to the product of the mean molecular mass of dry air, and the local ...
Burnley's Hannibal Mejbri competes against Preston North End players during the Sky Bet Championship match at Deepdale in Preston, England, on Saturday, Feb., 15, 2025.
The COSPAR International Reference Atmosphere (CIRA) 2012 and the ISO 14222 Earth Atmosphere Density standard both recommend NRLMSISE-00 for composition uses. JB2008 is a newer model of the Earth's atmosphere from 120 km to 2000 km, developed by the US Air Force Space Command and Space Environment Technologies taking into account realistic ...