Unit 4 - Earth Systems and Resources

earth's inner layers

solid crust, semi-solid mantle, liquid core, solid core

lithosphere

the solid part of the earth consisting of the crust and outer mantle

tectonic plates

sections of the Earth's crust that move due to convection currents.

oceanic plate

tectonic plate that is a thinner, denser and heavier type

continental plate

thicker but less dense plate that makes up most continents

plate boundaries

the edges of tectonic plates.

convergent

a boundary where earth's tectonic plates move toward each other. This causes a collision or subduction. This will result in the formation of volcanoes and mountain ranges.

divergent

plates move apart; forms new seafloor Ex-Mid-Atlantic Ridge

transform

Plates slide past each other; Ex: San Andreas Fault

subduction

a geological process in which one edge of a crustal plate is forced sideways and downward into the mantle below another plate

albedo

percent of solar radiation reflected by a surface, water has low, ice has high

earth's tilt

23.5°, the primary reason we have seasons

troposphere

first layer of atmosphere (smallest). Contains weather, greenhouse gases, air pollution.

stratosphere

the layer of the atmosphere that contains the ozone layer; temperature increases as you go up

mesosphere

the layer of the atmosphere between the stratosphere and the thermosphere and in which temperature decreases as altitude increases

thermosphere

the outermost shell of the atmosphere, between the mesosphere and outer space, where temperatures increase steadily with altitude.

weather

the meteorological conditions: temperature and wind and clouds and precipitation for the day

climate

the weather in some location averaged over some long period of time

wind

created from areas of uneven heating resulting in density differences between cold/warm air masses.

convection current

the movement of water (vapor) caused by differences in temperature, that transfers heat from one part of the water (vapor) to another. Also occurs in mantle (magma-->moving plates) & Oceans (currents)

hadley cells

convection current in the atmosphere that cycles between the equator and 30° N and 30° S.

trade winds

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

el nino

a weather pattern predominantly in the Pacific created by the warming of the waters off the west coast of South America, which pushes warm water and heavy rains toward the Americas and produces drought conditions in Australia and Asia. Leads to decline in commercial fish industry.

la nina

the water in the Eastern Pacific Ocean is cooler than usual-opposite from El Nino; leads to more upwellings; more nutrient-rich water; more fish.

watershed

land area (drainage basin) that delivers water, sediment, dissolved substances, pollution via small streams to a major river, downstream.

estuary

extremely fertile area where a river meets an ocean; contains a mixture of freshwater and saltwater and serves as a nursery for many species of fish

mechanical weathering

type of weathering in which rock is PHYSICALLY broken into smaller pieces.

chemical weathering

a process that changes rock into a new substance through interactions among elements in the air or water and the minerals in the rock

biological weathering

any weathering that's caused by the activities of living organisms.

horizons

different layers of soil

O horizon

Contains the greatest concentration of organic matter, surface plant and animal litter forms humus; able to retain water and nutrients

A horizon

1st true soil layer; is a porous mixture of the partially decomposed bodies of dead plants/animals called "humus" and inorganic materials such as clay, silt, and sand. Very fertile soil (top soil) that produces high crop yields.

B horizon

lighter colored subsoil beneath the A horizon; zone of accumulation in which nutrient minerals that leached out of the topsoil and litter accumulate

C horizon

horizon made of rock fragments on top of unweathered bedrock

plant essential nutrients

N, P, K

soil textures

clay (smallest), silt, sand (largest)

clay

a soil type that is made up of very small particles (less than .004 mm), that takes up water slowly and has a long water-retention time.

sand

coarse, gritty, large soil particles that may be easily seen and allow air and water into the soil, low water-holding capacity

loam

perfect agricultural soil with equal portions of sand, silt, and clay; highest amounts of nutrients/most fertile.

erosion

The process by which wind, water, ice, or gravity transports soil and sediment from one location to another. Moving water is the largest cause of soil erosion.

Different soil tests

soil triangle-determines soil type
Nutrient tests-determines N, P, K, pH
Permeability-determines flow of water through substance.

soil triangle

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

Layers of the atmosphere in order

troposphere, stratosphere, mesosphere, thermosphere, exosphere

What causes the layers in the atmosphere?

temperature differences

What causes wind?

uneven heating of the earth's surface (Convection currents + Coriolis effect)

angle of the sun's rays

Major factor in determining the amount of the Sun's energy an area receives. Earth is closer to the sun in the Northern hemisphere during WINTER.

rain shadow effect

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

Asthenosphere

The soft layer of the mantle on which the lithosphere floats. Convection currents here causes plate movement.