Climate
average weather that occurs in a giver region over a long period of time
Troposphere
layer of the atmosphere closest to the surface of Earth and containing most of the atmospheres mass
Stratosphere
layer of the atmosphere that contains the ozone layer
Albedo
percentage of incoming sunlight reflected from a surface
Saturation Point
maximum amount of water vapor in the air at a given temperature
Adiabatic Cooling
cooling effect of reduced pressure on air as it rises higher in the atmosphere and expands
Adiabatic Heating
heating effect of increased pressure on air as it sinks toward the surface of Earth and decreases in volume
Latent Heat Release
release of energy when water vapor in the atmosphere condenses into liquid water
Hadley Cells
convection current in the atmosphere that cycles between the equator and 30� N and 30� S.
Intertropical Convergence Zone (ITCZ)
area of Earth that receives the most intense sunlight; at equator, much evaporation and precipitation
Polar Cells
convection cell in the atmosphere, formed by air that rises at 60� N and 60� S and sinks at the poles
Coriolis Effect
deflection of an object's path due to the rotation of the Earth
Gyres
large-scale pattern of water circulation that moves clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere
Upwelling
upward movement of ocean water toward the surface as a result of diverging currents
Thermohaline Circulation
an oceanic circulation pattern that drives the mixing of surface water and deep water
El Ni�o-Southern Oscillation (ENSO)
periodic changes in winds and ocean currents, causing cooler and wetter conditions in the southeastern United States and unusually dry weather in southern Africa and Southeast Asia
Rain Shadow
region with dry conditions found on the leeward side of a mountain range as a result of humid winds from the ocean causing precipitation on the windward side
Biomes
a geographic region categorized by a particular combination of average temperature, precipitation, and distinctive plant growth forms on land, and a particular combination of salinity, depth, and water flow in water
Tundra
a cold and treeless biome with low-growing vegetation
Permafrost
an impermeable, permanently frozen layer of soil
Boreal Forests
A forest made up primarily of coniferous evergreen trees that can tolerate cold winters and short growing seasons.
Temperate Rainforests
A coastal biome typified by moderate temperatures and high precipitation.
Temperate Seasonal Forests
A biome with warmer summers and colder winters than temperate rainforests and dominated by deciduous trees.
Woodland/Shrubland
A biome characterized by hot, dry summers and mild, rainy winters.
Temperate Grassland/Cold Desert
A biome characterized by grassed prairies with cold, harsh winters, and hot, dry summers.
Tropical Rainforests
A warm and wet biome found between 20� N and 20� S of the equator, with little seasonal temperature variation and high precipitation.
Tropical Seasonal Forests/Savanna
A biome marked by warm temperatures and distinct wet and dry seasons.
Subtropical Deserts
A biome prevailing at approximately 30� N and 30� S, with hot temperatures, extremely dry conditions, and sparse vegetation.
Littoral Zone
The shallow zone of soil and water in lakes and ponds where most algae and emergent plants grow.
Limnetic Zone
A zone of open water in lakes and ponds.
Phytoplankton
Floating algae.
Profundal Zone
A region of water where sunlight does not reach, below the limnetic zone inn very deep lakes.
Benthic Zone
The muddy bottom of a lake, pond, or ocean.
Freshwater Wetlands
An aquatic biome that is submerged or saturated by water for at least part of each year, but shallow enough to support emergent vegetation.
Salt Marshes
A marsh containing nonwoody emergent vegetation, found along the coast in temperate climates.
Mangrove Swamps
A swamp that occurs along tropical and subtropical coasts, and contains salt-tolerant trees with roots submerged in water.
Intertidal Zone
The narrow band of coastline between the levels of high tide and low tide.
Coral Reefs
The most diverse marine biome on Earth, found in warm, shallow waters beyond the shoreline.
Coral Bleaching
A phenomenon in which algae inside corals die, causing the corals to turn white.
Photic Zone
The upper layer of water in the ocean that receives enough sunlight acting on compounds such as nitrogen oxides.
Aphotic Zone
The layer of ocean water that lacks sufficient sunlight for photosynthesis.
Chemosynthesis
A process used by some bacteria in the ocean to generate energy with methane and hydrogen sulfide.