3. atmosphere notes
DESCRIPTION
TRANSCRIPT
ATMOSPH
ERE NOTE
S
ATMOSPHERE:
Layer of gases that surround the Earth
COMPOSITION:
78% Nitrogen
21% Oxygen
.9% Argon
.1% Other Gases
ATMOSPHERIC PARTICLES:
• Water Vapor – from evaporation and transpiration, ranges from 1% (dry) to 4% (moist)
• Ozone – O3, absorbs harmful UV radiation, being destroyed by particulates
• Particulates – tiny solid particles such as ash, dust, pollen, microscopic organisms
ATMOSPHERIC PRESSURE:
• The pressure exerted on a surface by the atmosphere
• Decreases as altitude increases• Measured using a barometer
LAYERS OF THE ATMOSPHERE:
a) Troposphere
b) Stratosphere
c) Mesosphere
d) Thermosphere
TROPOSPHERE:
• Closest layer to the Earth• Where the weather is found• Temperature decreases as
altitude increases because its heated by Earth’s surface
STRATOSPHERE:
• Almost all the ozone (including ozone layer) in this layer
• As altitude increases temperature increases because UV rays absorbed by ozone
MESOSPHERE:
• Temperature decreases as altitude increases
• Coldest layer
THERMOSPHERE:
• As altitude increase temperature increases because oxygen and nitrogen atoms absorb solar radiation
RADIATION:
All the energy from the sun travels through space through radiation
Travels at 300,000 km/s
SCATTERING:
The deflection of solar radiation due to clouds, dust, water droplets, and gas particles
Thus sunlight hits the Earth surface from all directions and makes the sky blue
REFLECTION:
When solar radiation reaches the Earth surface it is either absorbed or reflected back into the atmosphere depending on the surface
ABSORPTION:
Absorbed solar radiation is converted into infrared waves (heat) and keeps the Earth warm
GREENHOUSE EFFECT:
The warming of the surface and lower atmosphere of Earth that occurs when carbon dioxide, water vapor, and other gases in the air absorb and re-radiation solar radiation
CONDUCTION:
The transfer of heat through a material through direct contact
Collisions between molecules in the atmosphere transfer heat energy
CONVECTION:
Warm air moves up as cool air sinks due to density differences.