Solar heat, gravity, Water/air transport: life impacts large
Earth's Atmosphere/Ocean: A dynamic system
-Heating from 'above' varies with latitude, with height in atmosphere, and with seasons
-Earth's rotaion, surface topography, and variable surface albedo (ice; land/sea) complicate it all
Atmospheric issues..Why do we care?
-Atmosphere is life sustaining
-Atmospheric dynamics control climate zones
-atmosphere plays central role in water cycle
What is the earth's atmosphere composed of?
1% mixture of minor gases dominated by argon.
Ninety-nine percent of the total mass of the atmosphere is contained in the first 40 to 50 miles (65 to 80 kilometers) above Earth's surface.
The atmosphere can be divided into layers based on atmospheric temperature and pressure
Final layer of the atmosphere, extending from the top of the thermosphere thousands of miles into space
A subregion within the thermosphere, extending from about 50 miles (80 kilometers) to more than 150 miles (400 kilometers) above Earth and containing elevated concentrations of charged atoms and molecules (ions)
The third layer of the atmosphere, extending from the stratosphere to about 50 miles (80 kilometers) above Earth
Energy in the form of waves or particles
The second layer of the atmosphere, extending from the tropopause, or top of the troposphere, to about 30 miles (50 kilometers) above Earth.
The fourth layer of the atmosphere, extending from the top of the mesosphere and extending about 400 miles (640 kilometers) above Earth
The atmospheric layer closest to ground level, extending up 5 to 10 miles (8 to 16 kilometers) above Earth.
Climate vs. Weather
Weather is short term
Climate is long term
ATmospheric Trace Gases
Carbon dioxide : (CO2) :360ppm
Water vapor : 1-4%
Ozone (O3) : 2-12ppm in stratosphere
Methane (CH4) : ~2ppm
Expands out in all directions from sun
ligth arrives at top of earths atmosphere non-uniformly
Incident light can boucne back into space
Reflection from light colored surfaces: clouds, snow, ice
ration of outgoing/incoming radiation
EARTH albedo is about .33
ANTARTIC is about .96
*one way to measure earths albedo is when earthsine lights up back side of moon
Deflection of light from its path
when photons impart energy or are absorbed by atmosphere or land