1. The Atmosphere Blanket of air that surrounds the earth and consists of a mixture of gasses – Goes 350 miles from earth’s surface – The air grows thinner the farther you get from earth’s surface – Life on earth supported by the atmosphere, solar energy, and earth’s magnetic fields – It absorbs energy from the sun, recycles water and other chemicals, and works with electrical and magnetic forces to have a moderate climate – Gasses include 78% nitrogen, 21% oxygen, 1 % other gasses like argon, CO2 and water vapor

2. Five Layers of the Atmosphere Troposphere Stratosphere Mesosphere Thermosphere Exosphere

3. Troposphere o Sea level up to 4 (at the poles) to 9 miles (at the equator) Air is very dense Where most weather takes place Temp drops 3.5 ⁰F every 1,000 ft in altitude Pressure decreases rate 1 inch per 1,000 ft Capped by tropopause which traps moisture and weather

4. Jet stream- strong air current – Flows east to west at 275 miles per hour – Signals boundary between hot and cold air – Pilots that fly at high altitudes must keep track of jet streams » If traveling east to west, stream provides tailwind (speeds it up) » If west to east then headwind, (increases time and cuts efficiency)

5. Stratosphere o Starts at troposphere and extends 30 miles Air is drier and less dense Temperature rises in this region 26.6⁰ F as gain altitude because it absorbs UV radiation from sun – Ozone layer which absorbs and scatters UV radiation is in this layer 99% of air is in the troposphere and stratosphere

6. – Mesosphere runs from the stratosphere up to 53 miles high Temperature decreases as low as -135.4⁰F as increase in altitude – Thermosphere runs from mesosphere to more than 350 miles Temperature increases as high as 3,140.6⁰ F because the sun’s energy is absorbed – Exosphere runs from thermosphere to edges of space, so 6,200 miles

8. Changes in Phases – Evaporation- Liquid to gas (water to water vapor) – Sublimation- solid to gas, skips liquid state (ice to water vapor) – Condensation- from gas to liquid (water vapor to water) – Deposition- from gas to solid, skips liquid state (water vapor to ice)

9. Oceans hold 97% of worlds water – Source of 86% evaporation on planet Requires heat, to destroy bond in water molecule to let the water evaporate

10. Humidity Amount of water in atmosphere at any given time – In southeastern US humidity about 75-90%, in west rarely high humidity – Dew point- temperature at which air can hold no more moisture When temperature falls to here, the air is saturated and water condenses as fog or rain or hail

11. Particulate Matter Water goes through complex process before fall as rain – Water vapor and cloud droplets make up cloud – When look at cloud only see cloud droplets – Takes million cloud droplets to form one raindrop – To make a rain drop water vapor must cling to particulate matter (materials in air in tiny particles like dust, or salt) – These particles act as the core of the rain drop

12. Atmospheric Pressure – Unequal heating of earth’s surface affects air pressure – Invisible gas particles that make up atmosphere create this atmospheric pressure – Altitude, temperature, and air density determine how much pressure particles apply – Pressure greatest at sea level where gas particles close together, as altitude increases more space between particles so pressure drops – IMPORTANT for flight, esp. during take off, climb, and landing

13. Coriolis Force 1832 French scientist, Gustave-Gaspard Corolis came up with theory to explain atmospheric circulation – If earth was stationary high pressure areas would flow straight to equator, but since it does not the rotation creates Coriolis Force (affects large bodies like air masses) – Force deflects air to right in northern hemisphere, air takes curved path – In south the force pushes air left in a curve – Size of curve depends on latitude and moving body’s speed – Deflection greatest at poles and decreases to zero as reach equator

14. How layers of atmosphere affect flight – Troposphere is where most flight takes place – Factors to take into account= air density, temp, and pressure Density- at low altitudes density of air increase – When air less dense- engines and propellers less efficient, and generate less thrust – Lift decreases because thin air exerts less force Drag decreases Takeoff and landing distances increases because takes longer to create enough air flow for lift

15. Pressure – At sea level it is perfect for health – But at 18,000 feet, where aircraft can conserve fuel and avoid bad weather, pressure drops to level that is fatal to humans (can’t get enough oxygen) – SO pressurized cabins, holds air under higher pressure (must be = to altitude at sea level) Temperature- – Airplanes have system to regulate temperature and heat cabins

16. Weather Balloons Since 1918 used to measure qualities about the atmosphere – Balloons filled with Helium, Hydrogen, and other natural gasses – National weather service releases the balloons 2x’s a day at 100 locations in US 75,000 balloons a year! They rise 100,000 feet (2 miles) and over 2 hrs drift up to 200 miles – Meteorologist use this to predict thunderstorms, hurricanes, aircraft icing, jet stream positions and temp – When it rises too high it pops, floats back to earth with message “Harmless weather instrument”, smells like rotten eggs, has paid mailbag to send it back

17. Atmosphere Game http://www.purposegames.com/game/899