Atmosphere: The blanket of gas surrounding Earth.
Three basic parts of the Earth are: atmosphere ( gas layer surrounding Earth), lithosphere (solid parts of Earth), and hydrosphere (water parts of Earth). We will study these parts separately, starting with the atmosphere.
air The mixture of gases that make up the atmosphere, including oxygen, nitrogen, carbon dioxide and water.
atmosphere The blanket of gas surrounding Earth.
air pressure Another name for atmospheric pressure.
atmospheric pressure The measure of the pressure that the atmosphere exerts on surfaces.
barometer An instrument used to measure the atmospheric pressure.
barometric pressure Another name for atmospheric pressure.
carbon dioxide Colorless, odorless gas that makes up about 0.03 percent of the gases in air.
pressure A force applied to an area of a surface.
water Chemical that makes up a very small percent of the gases in air.