Earth and Space Science: Earth Systems and Cycles
What this domain tests
Earth has four systems that interact: the geosphere (rock and land), the hydrosphere (water), the atmosphere (air), and the biosphere (living things). Know the water cycle: evaporation, condensation, precipitation, and collection, driven by energy from the Sun. Understand the rock cycle, in which rocks change among igneous, sedimentary, and metamorphic forms through melting, cooling, weathering, and heat and pressure.
Cycles and change
Know that weathering breaks rock down, erosion moves the pieces, and deposition drops them. Understand that Earth's surface changes slowly through processes such as erosion and quickly through events such as volcanic eruptions. Know that soils form from broken rock and decayed plant and animal material, and that natural resources such as water, soil, and fuels should be conserved.
Traps to watch for
Questions often confuse weathering with erosion, or claim the water cycle creates new water. Another trap is saying the Sun is not involved in the water cycle, or that all rocks form the same way. Watch for answers that treat one Earth system as separate from the others.
Rule of thumb
Ask "which system moves this material, and what drives it?" For example, water evaporating from a lake moves from the hydrosphere to the atmosphere, driven by the Sun's energy, and later returns as precipitation.