APES Unit 4: Earth System and Resources

plate tectonics

The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle.

Albedo

the percentage of incoming sunlight reflected from a surface

Troposphere

The lowest layer of Earth's atmosphere

Stratosphere

2nd layer of atmosphere; extends from 10 to 30 miles up; location of ozone layer; absorbs 95% of Ultraviolet radiation; temperature increases with altitude increase.

Mesosphere

3rd layer of the atmosphere

Thermosphere

The uppermost layer of the atmosphere, in which temperature increases as altitude increases

Exosphere

The outer layer of the thermosphere, extending outward into space.

Tsunami

A giant wave usually caused by an earthquake beneath the ocean floor.

oceanic crust

earths crust located under the ocean

continental crust

The portion of the earth's crust that primarily contains granite, is less dense than oceanic crust, and is 20-50 km thick

convergent boundary

A tectonic plate boundary where two plates collide, come together, or crash into each other.

divergnt plate boundary

plates moving away from each other

transform fault boundary

an area where tectonic plates move sideways past each other

earthquake

Shaking and vibration at the surface of the earth resulting from underground movement along a fault plane or from volcanic activity

subduction zone

The region where oceanic plates sink down into the asthenosphere.

Mantle

The layer of hot, solid material between Earth's crust and core.

Aesthenosphere

a layer of softer, weaker rock beneath Earth's lithosphere, which can flow slowly

Lithosphere

A rigid layer made up of the uppermost part of the mantle and the crust.

atmosphere

A thin layer of gases surrounding Earth

Atmosphere gases

Mixture of gases, nitrogen most abundant (78%), oxygen (21%)

El Nino-Southern Oscillation (ENSO)

The 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.

La Nina Effect

A change in the surface water temperature in the Pacific Ocean that produces a cold current.

trade winds

prevailing winds that blow from east to west from 30 degrees latitude to the equator in both hemispheres

Westerlies

prevailing winds that blow from west to east between 30 degrees and 60 degrees latitude in both hemispheres

Coriolis effect

The effect of Earth's rotation on the direction of winds and currents.

Leaching

Process in which various chemicals in upper layers of soil are dissolved and carried to lower layers and, in some cases, to groundwater.

Soil horizons in order

O, A, E, B, C, R

O Horizon (organic layer)

leaf litter, most soil organisms and partially decomposed organisms.

A Horizon

topsoil

E horizon (zone of leaching)

soil horizon that is the zone of leaching, characterized by the downward movement of water and removal of fine-grained soil components

B horizon

A soil horizon composed primarily of mineral material with very little organic matter

C horizon

The least-weathered soil horizon, which always occurs beneath the B horizon and is similar to the parent material.

R horizon

The bedrock, which lies below all of the other layers of soil, is referred to as the R horizon.

Permeability

Ability of rock or soil to allow water to flow through it

Porosity

the volume of open spaces in rock or soil

sand

A naturally occurring grainy material made of finely divided rock and mineral particles; the most common ingredient is silica. The largest soil particle size.

silt

A mixture of rich soil and tiny rocks. The second largest soil particle.

clay

the finest soil, made up of particles that are less than 0.002 mm in diameter.

Weathering

The chemical and physical processes that break down rock at Earth's surface.

Erosion

Processes by which rock, sand, and soil are broken down and carried away (i.e. weathering, glaciation)

Physical Weathering Examples

Heating and cooling, burrowing animals, frost wedging, mineral wedging, and root wedging

chemical weathering examples

Rusting (oxidation), Acid Rain, and plant acids

rain shadow effect

Precipitation falls on the windward side of a mountain range, resulting in lush vegetation & a warm, moist climate on one side, but a desert area on the leeward side.

climate

Overall weather in an area over a long period of time

weather

day-to-day conditions of the atmosphere, including temperature, precipitation, and other factors

Convection

Process by which, in a fluid being heated, the warmer part of the mass will rise and the cooler portions will sink.

Hadley Cell

a system of vertical and horizontal air circulation predominating in tropical and subtropical regions and creating major weather patterns.

soil triangle

used to determine textural classes of soil from the percentages of sand, silt, and clay in the soil

Seasons

Caused by the tilt of Earth on its axis as it revolves around the Sun

Winter Solstice (Northern Hemisphere)

shortest day of the year for the Northern hemisphere on December 21

Summer Solstice (Northern Hemisphere)

occurs on June 21, and marks the beginning of summer (this is the longest day of the year).

Equinox

The two days of the year on which neither hemisphere is tilted toward or away from the sun

angle of insolation

The angle at which the sun's rays strike the earths surface

Watershed

An ecosystem where all water runoff drains into a single body of water

Tributary

A stream or river that flows into a larger river