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The lower stratosphere is centered around 18 kilometers above Earth's surface. The stratosphere image is dominated by blues and greens, which indicates a cooling over time. [1] Diagram showing the five primary layers of the Earth's atmosphere: exosphere, thermosphere, mesosphere, stratosphere, and troposphere. The layers are not to scale.
These figures should be compared with the temperature and density of Earth's atmosphere plotted at NRLMSISE-00, which shows the air density dropping from 1200 g/m 3 at sea level to 0.125 g/m 3 at 70 km, a factor of 9600, indicating an average scale height of 70 / ln(9600) = 7.64 km, consistent with the indicated average air temperature over ...
The "highway" program or Highway Fuel Economy Driving Schedule (HWFET) is defined in 40 CFR 600.I. [10] It uses a warmed-up engine and makes no stops, averaging 48 mph (77 km/h) with a top speed of 60 mph (97 km/h) over a 10-mile (16 km) distance. The following are some characteristic parameters of the cycle: Duration: 765 seconds
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 ...
The International Civil Aviation Organization (ICAO) published their "ICAO Standard Atmosphere" as Doc 7488-CD in 1993. It has the same model as the ISA, but extends the altitude coverage to 80 kilometers (262,500 feet). [7] The ICAO Standard Atmosphere, like the ISA, does not contain water vapor. Some of the values defined by ICAO are:
Geocentric orbits with altitudes at apogee higher than 100 km (62 mi) and perigee that intersects with the defined atmosphere. [4] Low Earth orbit (LEO) Geocentric orbits ranging in altitude from 160 km (100 mi) to 2,000 km (1,200 mi) above mean sea level. At 160 km, one revolution takes approximately 90 minutes, and the circular orbital speed ...
From Earths surface to the top of the stratosphere (50 km) is just under 1% of Earth's radius. The mesosphere ( / ˈ m ɛ s ə s f ɪər , ˈ m ɛ z -, ˈ m iː s ə -, - z ə -/ ; [ 1 ] from Ancient Greek μέσος ( mésos ) 'middle' and - sphere ) is the third layer of the atmosphere , directly above the stratosphere and directly below the ...
The troposphere is the lowest layer of the Earth's atmosphere; it starts at the planetary boundary layer, and is the layer in which most weather phenomena occur. The troposphere contains the boundary layer, and ranges in height from an average of 9 km (5.6 mi; 30,000 ft) at the poles, to 17 km (11 mi; 56,000 ft) at the Equator.