EARTHS ATMOSPHERE Atmosphere layers of gases that surround

EARTH’S ATMOSPHERE

§ Atmosphere - layers of gases that surround our planet § The Earth’s atmosphere is made up of several things. The two biggest parts are nitrogen and oxygen § Nitrogen - makes up around ¾ or 75% of the atmosphere § Oxygen - makes up around 1/5 or 20% of the atmosphere § The other 1%-5% or so is made up of lots of other gases - one being carbon dioxide

LAYERS § The Earth’s atmosphere is divided up into 4 major layers. As you go up through the atmosphere, air pressure decreases.

TROPOSPHERE § The layer we live in. Bottom layer of the atmosphere, closest to Earth’s surface. § Earth’s weather happens in the troposphere. § Goes from earth’s surface up 12 km § As you go up through the troposphere the temperature decreases.

STRATOSPHERE § Second layer up from Earth’s surface § As you go up through the stratosphere the temperature increases. This happens because the ozone layer is found in the upper stratosphere. Takes energy from sun and turns it to heat. Remember the greenhouse effect - heat gets trapped by something (gases, water vapor, etc. )

MESOSPHERE § Third layer up from Earth’s surface § Mesosphere is coldest layer of the Atmosphere § As you go up through the mesosphere, temperature decreases § Protects us from meteors. So cold they burn up.

THERMOSPHERE § Outermost layer of the atmosphere. Goes into outer space. No real end. No sign or line that says “Earth ends here, Space starts here!” § As you go up temperature increases. Real hot! Sun’s rays hit here first, and gets turned into heat. Remember particles far apart so wouldn’t show up on regular thermometer.

THERMOSPHERE part 2 § Divided into two parts. – Ionosphere - Electrically charged particles from sun’s energy (rays) running around here. Where radio waves found here and northern lights. – Exosphere - outer layer of thermosphere. Where satellites, long distance phone signals, tv signals come from. Weather is watched from here too.