Atmosphere IVital Statistics
4.6 billion years
199 million square miles
One of the Terrestrial planets (Earth, Mars, Mercury, Venus)…with a small mass
Vocabulary
Weather- condition of Earth’s atmosphere at a particular time/place
Atmosphere- layer of gases that surround the planet.
Climate- set of particular weather conditions averaged over a period of time.
Why do we need the atmosphere?
1-Traps 02 and other gases so we can breath!
2-Keeps H20 at a liquid state!
3-Protects us from dangerous levels of radiation (EM)
IV. Earth’s Atmosphere
78% of the Earth’s atmosphere is _______
21% of the Earth’s atmosphere is _______
1% of the Earth’s atmosphere is made up of Ozone, CO2, H20 and Argon (trace materials)
Nitrogen
Oxygen
The Earth’s Early Atmosphere
Hydrogen, Ammonia (toxic) and Methane (toxic). These gasses were light and with the Earth’s small gravity + the sun were broken up.
How did we get the atmosphere that we have today?
1)
2)
Comets may have pounded the Earth bringing water and other elements with them.
Where did our water come from?
Ancient plant life and the process of photosynthesis helped to create oxygen.
Water is split by UV light. Hydrogen rises and leaves the Oxygen.
Helps to repair body cells
Some plants convert nitrogen into nitrates…we eat plants/animals that have converted nitrates into protein.
Oxygen
Respiration
Fire
Rust
co2
Photosynthesis
Other planets atmosphere’s
__________ and the Moon have no atmosphere (small size)
__________ and Mars are similar to the Earth (they have a secondary atmosphere)
__________ and Saturn have their original atmosphere (large size)
Mercury
Venus
Jupiter
Our atmosphere is compressed. This is why it is more difficult to breathe at higher altitudes…the air is less dense and thinner (less oxygen.)
Layers of the Atmosphere
Stratosphere
80,000 feet and up
O2 is broken by UV (high energy/frequency) which eventually forms O3 or ozone.
A. Ionosphere
Greenhouse Effect
The Greenhouse effect doesn’t create heat, it slows the loss of heat.
It creates wind/weather!
Balanced because all molecules are receiving pressure in all directions.
How do we measure air pressure?
Barometer- instrument used to find air pressure.
Record pressure in Pascals (Pa) or millibars.
Denver, CO- 835 mb due to the higher altitude
Air pressure varies
Air pressure changes with temperature.
As molecules move further apart there is less pressure. As molecules move closer together (colder weather) more pressure.
Air pressure varies
Warm air moves molecules faster and further apart (they rise)
Cold air moves molecules slower and closer together (they sink)
Convection!
Humidity can effect air pressure.
Water vapor causes air to be lighter (less N and O are present) 97%
Dry air 99% N,O