History of Earth
Name the supercontinent that existed before continents split.
Pangaea
What is Earth’s main external energy source?
Sun
Long-term average of weather is called?
Climate
What causes Moon phases?
Moon’s position relative to Sun and Earth
What star is at center of our solar system?
Sun
Explain the law of superposition
Oldest layers are deeper
What causes wind and surface currents?
Unequal heating → pressure differences
One human activity that raises greenhouse gases?
Burning fossil fuels
Why do seasons happen?
Tilt of Earth’s axis
Where are most asteroids located?
Asteroid belt (Mars–Jupiter)
What do we call a fossil that serves a a reference point for geologic time?
index fossil
What makes winds and currents curve on Earth?
Coriolis effect
One record used to study past climates?
Ice cores
When does a solar eclipse occur?
Moon between Earth and Sun (new moon)
One key difference: planet vs. dwarf planet.
Planet cleared its orbit; dwarf planet did not
Give two rock clues to past environments.
Fossils, law of superposition
How do warm oceans strengthen hurricanes?
Evaporation adds heat and moisture
Weather vs. climate — short difference + example.
Weather = short-term (today’s rain); Climate = long-term average (regional winters)
How does tilt affect summer vs. winter?
Tilt toward Sun = higher sun angle + longer days → warmer
What is the shape of our galaxy the milky way
spiral
If the half-life of carbon-14 is 5700 years and a fossil has 1/8th the carbon-14 its supposed to have, how old is it?
17100
What drives deep ocean circulation?
Differences in temperature and salinity (thermohaline)
Two measurable signs climate is changing.
Rising global temperatures; higher CO2 levels
One orbital/tilt change that affects long-term climate.
Changes in Earth’s tilt (obliquity)
red-shift