Essential Vocabulary and Questions Title: Atmosphere 3) “I can name the different layers of the atmosphere and their unique physical properties” 4) “I can evaluate the parts of the atmosphere that reflect and absorb energy.” 5) “I can reason that the greenhouse effect is a natural process where gases trap heat, keeping Earth warm.” Key Information, Models and Definitions The Atmosphere What is Earth’s Atmosphere? Atmosphere = the mixture of gases that surrounds Earth -­‐ Mostly made of nitrogen (78%), oxygen (21%) o Other gases = 1% o How do pressure and temperature change in the atmosphere? Air pressure = measure of the force that air molecules push on an area of a surface What are the layers of the atmosphere? Thermosphere -­ -­‐ uppermost layer -­‐ temp increases with altitude Mesosphere -­ -­‐ meteoroids burn up here -­‐ temp decreases with altitude Stratosphere -­ -­‐ ozone absorbs UV radiation here -­‐ temp increases with altitude Troposphere -­ -­‐ lowest layer -­‐ temp decreases with altitude -­‐ weather happens here -­‐ 80% of the atmosphere’s total mass How does the atmosphere protect life on Earth? 1) By absorbing or reflecting harmful radiation a. Ozone layer i. area in the stratosphere where ozone is highly concentrated ii. absorbs most solar radiation 2) By maintaining the right temperature range a. Greenhouse effect = where gases in the atmosphere (like water vapor and CO2) absorb and give off infrared radiation, keeping the Earth warm Summary