Chapter 5: Global Changes

Greenhouse gas

Gases such as CO2 that trap heat in the atmosphere

Hydrocarbons

Molecules that contain only carbon and hydrogen; ex. Methane and forms of other natural gas

Climate

Average characteristic conditions of the atmosphere over long periods of time

Albedo

Reflectivity of light (i.e from ice or land)

Hydrologic (water) cycle

Involves evaporation, transpiration, condensation and precipitation

Tectonic cycle

The creation and destruction of the lithosphere (outermost layer of earth, including mantle and crust)

Divergent plate boundaries

Tectonic plates move away from each other; creates seafloor spreading

Convergent plate boundaries

Plates move toward each other and collide; creates subduction zones

Transform fault boundary

Tectonic plates move sideways past each other; leads to seismic activity (earthquakes) and fault zones

Richter scale

Measures the largest ground movement during an earthquake

Igneous rock

Formed directly from magma

Sedimentary rock

Formed when sediment is compressed by overlying sediment

Metamorphic rock

Formed when any type of rock is subjected to high temperature and pressure

Anaerobic

Characterized by the absence of free oxygen

Upwelling

Rising cold water currents

Thermohaline circulation

Drives the mixing of surface water and deep water