Download Earth and Space Science

8th Grade Science Content Strand 4
• Lithosphere- crust + upper mantle; solid,
rigid, brittle; broken into plates; sits on top
of asthenosphere
• Asthenosphere- mantle; plastic, flowing,
hot; this is where the convection currents are
• Oceanic- thinner, more dense, made of
basalt rock
• Continental- thicker, less dense, made of
granite rock
• Faulting- tension forces, pulling apart; normal fault
• Faulting- compression forces, squeezing together; reverse fault
• Folding - compression forces, squeezing together
• Causes plates to move
• Hot rocks in the mantle rises and sinks
• Pangaea- supercontinent 200 million years
ago
• Evidence
• Similar fossils on different continents
• Continents fit together like a puzzle
•Warm weather fossils in cold places like
Spitzbergen
• Convergent - come together
• Oceanic-continental: oceanic sinks, subduction,
volcanoes
•Oceanic-oceanic: trench, subduction, island arc
• Continental-continental: mountains
• Divergent- move apart
• Oceanic-oceanic- seafloor spreading, midocean ridge
•Continental-continental- rift valley, volcanoes
• Transform- slide past each other
• Earthquakes, San Andreas Fault
• Primary (P) waves- faster
• Secondary (S) waves- slower
• Surface waves- cause most damage
• Waves move faster through solids (more
dense) than liquids.
•
•
•
•
•
Cold front- thunderstorms then cool, dry air
Warm front- light rain then warm, humid air
High pressure- clear, sunny (happy weather)
Low pressure- cloudy, rainy (lousy weather)
Isobars- lines that connect areas of equal air
pressure
• Trade winds (easterlies)- blow from east to
west near the equator; steer hurricanes when
they first form
• Prevailing westerlies- blow from west to east
across the US
• Jet streams - blow from west to east high
across the US
•
•
•
•
•
•
Lower air pressure= faster winds
Trade winds- move hurricanes to west
Westerlies- blow them back to the east
Warm water- strengthens hurricanes
Cold water/land - weakens hurricanes
CANNOT predict path of hurricane with 100%
accuracy!
• Causes: Too much CO2 in atmosphere
• Burning fossil fuels (coal, oil, natural gas)
• Deforestation (cutting down trees)
• Ways to Reduce:
• Recycle
• Walk or ride bicycle
• Energy efficient appliances
• Fluorescent bulbs
• Use renewable energy
• Renewable- solar, wind, hydroelectric,
geothermal, biomass
• Nonrenewable- fossil fuels (oil, coal,
natural gas), metals, nuclear (uranium)
• Caused by tilt of the Earth
• During winter, tilted AWAY from sun; shorter daylight hours
• Spring equinox - equal day and night hours; tilted neither toward
nor away from sun
• During summer, tilted TOWARD sun; longer daylight hours
• Fall equinox - equal day and night hours; tilted neither toward nor
away from sun.
• Tropical- near equator, warm year round, most
direct sunlight
• Temperate- middle latitudes, warm summers,
cool winters
• Polar- summer temperatures much higher than
winter
• Age: 13.7 billion years
• Largest to smallest - universe, galactic cluster,
galaxy, solar system, Earth
• Milky Way- spiral galaxy, Sun is located in a
spiral arm
• Red shift (long wavelength) shows universe is
expanding.
• Hotter stars give off higher energy radiation.
• Short wavelength=high energy
• Bluish-white stars give off ultraviolet.
• Use of plants to make medicines, improve
crops
• Using renewable resources instead of
nonrenewable
• Found in nature, so they decompose
naturally