Air pressure decreases with altitude. The combined weight of air molecules at increasing altitude decreases. Air pressure is greatest at the Earth's surface, because the surface air molecules bear the combined weight of ... More »

As altitude increases, the air pressure decreases. The surface of the earth is the bottom of an ocean of air. The layers on top increase pressure so that at sea level a body is under 14.7 pounds of pressure per square in... More »

Atmospheric pressure decreases as altitude increases. High altitudes contain less air molecules, resulting in lower air density, decreased temperatures and lower air pressure. High altitudes are typically found above sea... More »

Air pressure changes with altitude because of issues related to gravity. Molecules have more weight the closer they are to the Earth and more of them move to lower elevations as a result; this causes increased pressure b... More »

Air pressure is caused by the weight of the air pressing down on the Earth, the ocean and the air below. Air pressure is also known as atmospheric pressure and barometric pressure. More » Science Earth Science

Air pressure is the amount of pressure the weight of air exerts on a specific point. In terms of weather, air pressure is measured in millibars, hectopascals or inches of mercury. For items such as tires and other inflat... More » Education

Air pressure, the force exerted on a mass by the weight of air particles, is measured in either inches of mercury or in millibars, represented by inHg and mb, respectively. One standard atmosphere, represented by the sym... More »