Earth's Composition

Question 1

Density equation

Answer 1

mass / volume

Question 2

Density of water

Answer 2

1 g/cm^3

Question 3

Average density of earth

Answer 3

5.52 g/cm^3

Question 4

Earth’s Atmosphere

Answer 4

Extends 100km above surface, 77% nitrogen, 21% oxygen, 2% argon, water, carbon dioxide

Question 5

Oblate Spheroid

Answer 5

Earth bulges around equator, slightly squashed sphere, makes gravity weaker at the equator

Question 6

Crust

Answer 6

Outermost layer of earth, DENSITY 3 g/cm^3, 100km thick, continental crust is thick and less dense, and oceanic crust is thin but more dense,

Question 7

Mantle

Answer 7

Majority of earth, hot moving rock in upper mantle (taffy like), moves continents, crust to 2900 km, density 3 g/cm^3 at top and 9 g/cm^3 at bottom

Question 8

Core

Answer 8

Mantle to center of earth, outer core is molten, inner core is solid, creates earth’s magnetic field, density 9 g/cm^3 at top and 13 g/cm^3 at center

Question 9

Order of Earth’s interior

Answer 9

crust - mantle- liquid core - solid core (will need to be able to draw)

Question 10

Seismic Waves

Answer 10

earthquakes, helps us understand the internal structure of earth

Question 11

P waves

Answer 11

Travel through liquid and solids, straight line

Question 12

S Waves

Answer 12

Can only travel through solids, shows us the upper mantle is molted, bounces, important for understanding interior

Question 13

Plate Tectonics

Answer 13

Multiple plates make up earth, move over the mantle to form crevasses, faults, or mountains and volcanoes, driven by CONVECTION CURRENT

Question 14

Pangea

Answer 14

Ancient super continent, we know because continents fit together like a puzzle, fossils match on far away continents, rocks of same ancient types

Question 15

Earthquake Epicenters

Answer 15

Earthquakes are when stress builds up between plates, this energy is concentrated at the epicenter

Question 16

Divergent Boundaries

Answer 16

Plates move away from each other, small earthquakes

Question 17

Convergent Boundaries

Answer 17

Plates move towards each other, large earthquakes with volcanic activity

Question 18

Transform Boundaries

Answer 18

Plates slide past each other, shallow but destructive earthquakes, San Andreas Fault

Question 19

Ring of Fire

Answer 19

High are of tectonic activity, 75% of all earthquakes occur here, where tectonic plates meet, all coastline surrounding pacific ocean

Question 20

Earth’s Magnetic Field

Answer 20

generated by movement of molten metal in the outer core (swirls since inner core is warmer), geodynamo (cycle between changing electric and magnetic fields), poles move over time and reverse every 100,000 years

Question 21

Magnetosphere of Earth

Answer 21

Magnetic field protects us from solar winds, charged particles circle back to poles, when they hit the atmosphere at the poles aurora occurs

Question 22

Solar Wind

Answer 22

Harmful, destroys our atmosphere

Question 23

Color of Aurora

Answer 23

Depends on what type of molecules are struck by the charged particles and atmospheric level,
green = oxygen 60 miles up
red = oxygen 300 km up
purple and pink = neutral nitrogen
blue = ionized nitrogen at 100km
(colors is from particles dropping in energy)

Question 24

Aurora Ring

Answer 24

Where aurora occurs, circle around poles

Question 25

Earth’s Atmosphere Levels

Answer 25

Troposphere - Stratosphere - Mesosphere - Thermosphere

Question 26

Troposphere

Answer 26

0-12km, contains 75% of the gases in the atmosphere, where we live and where pretty much all weather occurs, thicker at equator and thinner at poles, temp decreases with altitude

Question 27

Tropopause

Answer 27

Layer between troposphere and stratosphere, jet stream is here

Question 28

Stratosphere

Answer 28

12-50km, contains ozone layer 15-35km (absorbs and scatters suns harmful UV rays), temp increases with altitude due to absorption of UV radiation

Question 29

Mesosphere

Answer 29

50-80km, temp decreases with alt., coldest layer, where meteors burn up due to dense friction

Question 30

Mesopause

Answer 30

Coldest part of earth’s atmosphere

Question 31

Thermosphere

Answer 31

80-100km, Air is very thin and hot, can reach temps of 2000 degrees C from UV radiation, ISS and auroras are found here

Question 32

Ionosphere

Answer 32

Contains charged particles that reflect radio waves, enabling long-distance communication

Question 33

Age of Earth

Answer 33

4.55 billion years, we know from radiometric dating (measuring decay of radioactive material, half-life)

Question 34

Carbon Dioxide levels in the atmosphere due to fossil fuel usage

Answer 34

Shot WAY up

Question 35

What carbon dioxide does to earth

Answer 35

raises earth’s temp, traps heat

Question 36

Representative Concentration Pathway (RCP)

Answer 36

Predictor of how CO2 levels will affect earth depending on their levels

Question 37

Effects of Climate Change

Answer 37

higher storm surges, rising sea levels, thermal expansion (water molecules spreading out as they get warmer), stronger storms, heatwaves, melting glaciers, acidic ocean, food insecurity, climate refugees, loss of biodiversity