Structure of the Atmosphere

Exosphere composition/density/pressure

-Air molecules are very sparse in this layer, almost the same as the airless void of outerspace -Only light gases like helium and hydrogen are found here -Most gas particles never hit another atom or molecule eventually arc back down into the lower atmosphere, a small portion of our atmosphere leaks into space each year and this way

Stratosphere temperature (as you increase in altitude)

-As you reach the ozone layer, ozone absorbs ultraviolet radiation making it hot

Mesosphere composition/density/pressure

-Composition is similar to troposphere and stratosphere -Air molecules are less dense(concentrated) in this layer so gases become somewhat separated based on types of chemical elements they contain

Stratosphere composition/density/pressure

-Contains similar composition as troposphere except there is lower density and lower pressure -Has the 'ozone layer' which keeps UV radiation out and traps some infrared radiation to keep us warm but not overheat -Air is roughly 1000 times dinner at top of stratosphere then at sea level

Thermosphere composition/density/pressure

-Gas molecules are sparse and widely spaced (not dense/low pressure) -Density is so low that most of the thermosphere is "outerspace" -Gas particles collide so in frequently that gases become separated by types of chemicals they contain -In Upper thermosphere atomic oxygen(O), nitrogen(N), and helium(He) are main components

Thermosphere temperature (as you increase in altitude)

-Molecules are heated faster because they're closer to the sun and absorb intense solar radiation -Temperatures climb sharply and then level off and solar activity strongly influences temperature -About 200°C hotter in daytime then at night and upper thermosphere ranges from 500 - 2000°C or higher

Troposphere composition/density/pressure

-Mostly uniform composition of nitrogen, oxygen, carbon dioxide, and water vapor and all other gases -Contains most of the atmospheric mass meaning most dense layer -Air pressure and density of the air decrease with altitude

How have humans changed the composition of the atmosphere?

-Overall we've been increasing various greenhouse gases -We have increased carbon dioxide levels by burning fossil fuels and increased human energy consumption -By clearing land like timber and farming there fewer trees to remove carbon dioxide from the atmosphere by photosynthesis and trees are burned releasing even more CO2 -Agriculture, pollution, and changing ozone are other ways also

Exosphere temperature (as you increase in altitude)

-Particles move so fast the temperature there it's quite hot however the exosphere would feel quite cold to us -We feel warm 20 particles hit our skin and transfer heat energy to us however there are too few particles in the exosphere to transfer much energy even though each particle is quite hot itself

Troposphere temperature (as you increase in altitude)

-Temperature decreases as altitude increases -The amount of heat absorbing molecules decrease as distance from Earth's surface increases which causes decreasing temperatures

What is special about the ionosphere? Where is it located?

-The ionosphere is part of the thermosphere and is where radio waves from earth are reflected back to earth -Ionosphere is full of electrically charged particles called ions -High energy solar photons tear electrons away from gas particles creating electrically charged ions

What is the overall composition of the atmosphere?

78% nitrogen gas (N2), 21% oxygen (O2), 1% other gases. Other gases include water vapor, carbon dioxide, Argon, helium, hydrogen, ozone particles etc.

Define atmosphere

All of the gases that surround the planet

Mesosphere temperature (as you decrease in altitude)

At the top the temperature is around -90°C -With The absence of ozone, temperature again decreases as the number of heat absorbing molecules decrease

From the surface of Earth to outer space, what is the order of the layers of the atmosphere?

Troposphere, Stratosphere, Mesosphere, Thermosphere (including ionosphere), and Exosphere (The Sun Makes Thermal Energy is to help remember order)