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Air pressure is an important factor which affects the resulting atmospheric climate conditions. It is the force of the air pressing down on the Earths surface. As air is all around us, there is air pressure all around us too. Near sea level there is more air above you than there would be on the top of Mount Everest, therefore the air pressure is higher near the sea than it is on the top of a mountain. Altitude Atmospheric Pressure Variation Air pressure decreases with altitude.
The exact reduction in pressure at a particular altitude depends on the weather conditions, but an average measure is 1 millibar for every 8 metres of altitude gain, up to about 2-3000 feet. Like with Mount Everest which stands 8,848m, the standard atmospheric pressure at its summit is between 310 and 360mB, compared to 1013mb at sea level (BBC 2006). Pressure varies smoothly from the earths surface to the top of the mesosphere. Although the pressure changes with the weather, NASA has averaged the conditions for all parts of the earth year-round.
Most of the atmospheres molecules are held close to the earths surface by the force of gravity, air pressure decreases rapidly at first, then more slowly at higher levels. Since more than half of the atmospheres molecules are located below an altitude of 5. 5 km, atmospheric pressure decreases roughly 50% (to around 500 mb) within the lowest 5. 5 km. Above 5. 5 km, the pressure continues to decrease but at an increasingly slower rate.
Reference
Weather at Altitude. 30 November 2006. British Broadcasting Corporation. 30 November 2006
The exact reduction in pressure at a particular altitude depends on the weather conditions, but an average measure is 1 millibar for every 8 metres of altitude gain, up to about 2-3000 feet. Like with Mount Everest which stands 8,848m, the standard atmospheric pressure at its summit is between 310 and 360mB, compared to 1013mb at sea level (BBC 2006). Pressure varies smoothly from the earths surface to the top of the mesosphere. Although the pressure changes with the weather, NASA has averaged the conditions for all parts of the earth year-round.
Most of the atmospheres molecules are held close to the earths surface by the force of gravity, air pressure decreases rapidly at first, then more slowly at higher levels. Since more than half of the atmospheres molecules are located below an altitude of 5. 5 km, atmospheric pressure decreases roughly 50% (to around 500 mb) within the lowest 5. 5 km. Above 5. 5 km, the pressure continues to decrease but at an increasingly slower rate.
Reference
Weather at Altitude. 30 November 2006. British Broadcasting Corporation. 30 November 2006