Atmosphere and Ocean

Nitrogen cycle Yeah!

8% at 8 min = fatal;

24% max for no effect
oxygen - 20% of the atmosphere; used by plants and animals for respiration - breathing and making food; includes ozone - a poisonous bluish form of oxygen with a strong odor; when ozone is produced on the ground from cars and factories, it is harmful and forms smog; from the middle to the top of the stratosphere is the ozone layer; the ozone layer acts like a shield that absorbs the sun’s ultraviolet (UV) energy which is destructive to life and causes cancer.

water vapor - varies between 1 to 4% of the atmosphere; heavy greenhouse gas; absorbs heat

carbon cycle Yeah!
argon - 1% of the atmosphere; inert gas (does not combine with anything); used in welding

carbon dioxide CO₂ - 0.04% of the atmosphere; produced when materials burn (combustion) and when humans and animals breathe out (respiration); heavy greenhouse gas; absorbs heat

trace = small amount
methane, hydrogen, CFC’s - trace greenhouse gases, less than 1 % of the atmosphere

helium, neon, krypton, xenon, radon - other inert trace gases, less than 1 % of the atmosphere

content – what types of gasses

The atmosphere extends out about 41,000 miles from earth’s surface to outer space, but most of the air is concentrated into the bottom two layers (troposphere and stratosphere - 0 to 30 miles above the ground) due to gravity. The layers beginning from the surface are:

these two are the lower atmosphere


these two are the upper atmosphere

troposphere, stratosphere

mesosphere, thermosphere