Earth’s ATMOSPHERE August 30, 2016

Atmosphere A layer of gases that surrounds the planet Makes conditions suitable for life on Earth Divided into several atmospheric layers extending from the Earth’s surface outward Temperature differences separate the layers Temperature decreases as the altitude increases

AIR PRESSURE Force exerted by the gases pushing on an object is greatest near the surface of the Earth Air pressure decreases through the layers farther out from the surface as Earth’s pull of gravity decreases

THE TROPOSPHERE The lowest layer of atmosphere that extends from the surface of the earth up to 6-20km high where air planes fly, and Earth’s weather and clouds occurs Air pressure is greatest here Water vapor & carbon dioxide are found which are important to weather conditions

THE STRATOSPHERE Contains the Ozone layer Ozone is a form of oxygen Cold throughout the layer except in the upper region (ozone) Extends from 20km up to 50km

THE MESOSPHERE Middle layer Coldest layer Meteors burn up in this layer Extends from 50km up to 85km

THE THERMOSPHERE Warmest layer Temperature increases it extends out Air is very thin Aurora Borealis (Northern Lights) occur in the lower part of this layer Extends from 86km up to 690km

THE EXOSPHERE The outermost layer of Earth’s atmosphere Cold temperature of outer space Satellites orbit the Earth within this layer. Extends from 691km up to 10,000km

THE ATMOSPHERIC GASES OXYGEN & NITROGEN 2 most common gases Found throughout all the layers Ozone is a form of oxygen TRACE GASES Some examples are argon, krypton, helium Are not significant in the atmosphere % of gases