Chapter 15: The Atmospherehttp://www.youtube.com/watch?v=AkaY1dvZer4 Section 1 : characteristics
What is the Atmosphere?? • It is a mixture of gases that surround Earth • It is always changing • Made up mostly of Nitrogen, with Oxygen in 2nd place. Following is argon, Carbon Dioxide, water vapor and other gases.
Pressure and Temperature • Pressure: force of which the air particles push on a surface • Ears pop, human pyramid example • Altitude: height of an object above Earth’s Surface • As altitude increases, pressure decreases • Temperature varies between colder and warmer, due to gases contained in the different layers
Layers of the Atmosphere • Four (Troposphere, Stratosphere, Mesosphere, thermosphere)
Troposphere • Lies next to earth’s surface, lowest one • 90% of atmosphere’s total mass • All of earth’s “stuff” found here
Stratosphere • Right above troposphere; air very thin, little moisture, extremely cold • Has OZONE---3 oxygen molecules and absorbs solar energy in the form of UV which warms the air and protects our surface
Mesosphere • COLDEST LAYER: BRRR • -93 degrees • Reach storm winds of 320 km/hr.
Thermosphere • Uppermost layer • Can become very hot? ( 1, 700 degrees) • Difference between heat and temp: Particles just move very fast • Ionosphere: upper part of thermosphere- particles become negatively charged like IONS • Northern Lights, radio waves