Unit 4: Earth Systems

convergent boundaries

a plate boundary at which plates come together

convergent boundary phenomena

mountains, island arcs, earthquakes, volcanoes

divergent boundaries

Places where plates are pulling apart

divergent boundary phenomena

seafloor spreading, rift valleys, earthquakes, volcanoes

transform boundaries

Places where tectonic plates slide along beside one another as they move

transform boundary phenomena

earthquakes

Layers of Earth by composition

crust

mantle

outer core

inner core

Layers of Earth by physical properties

lithosphere

aesthenosphere

lower mantle

outer core

inner core

tectonic plates

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

Alfred Wegener

A German scientist who proposed the theroy of continental drift

Pangeae

Supercontinent made up of our existing continents "all lands" existed 300 million years ago

convection currents

Circular currents in the mantle caused by the magma being heated by the core off the Earth.

magma upwelling

the rising of magma due to convection currents

Hot spot formation

magma emerges through crust and plates move over causing volcanic islands or volcanoes on land

types of weathering

physical, chemical, biological

weathering

The breaking down of rocks and other materials on the Earth's surface.

physical weathering

the mechanical breakdown of rocks and minerals

ex: wind, water, freezing, glaciers

chemical weathering

The process that breaks down rock through chemical changes

ex: oxidation, hydrolysis, acid rain

biological weathering

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

ex: animal guano, lichen

contents of soil

Sand, silt, clay, humus, nutrients (ammonium, phosphates, nitrates), water air, living organisms

components of heathy soil

1. creates a nutrient cycle

2. water/percolation

3. habitat

4. plants

Humus

material formed from decaying leaves and other organic matter

Erosion

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

factors impacting rate of soil formation

1. parent material (changes pH and nutrients)

2. topography/slopes (more slope = less stable = less decomposition)

3. climate (warmer = faster)

4. precipitation

5. soil organisms

6. time (decades v millennia)

soil horizons in order

O, A, E, B, C, R

O-horizon

Organic material, shallow roots, leaves, animal waste, provides nutrients and traps moisture to avoid drying out

A-Horizon

Decomposed humus, houses bio activity, holds much of the nutrients

B-Horizon

Sub-soil

Lighter in color (more clay and less humus), less organic material

c-Horizon

parent material, least weathered, most in tact rock, some beak down of inorganic material

R-horizon

The bedrock, which lies below all of the other layers of soil.

e-horizon

eluviated layer, zone of leaching, material dragged down to this layer

Eluviation

the washing out of fine soil components from the A horizon by downward-percolating water

characteristics of soil

color

texture

pH

friability

Friability

How easily the soil can be crumbled.

Black/dark soil

color of soil denoting soil that is rich in organic matter and thus, fertile

pale grey soil

color of soil denoting leaching

Porosity

The percentage of the total volume of a rock or sediment that consists of open spaces

soil with the most interstitial space has the highest porosity

interstitial space

the space between pieces of soil

loam

Rich, fertile soil that is made up of about equal parts of clay, sand, and silt. approximately: 40-40-20, sand-silt-clay

low pH soil

pH creating high leaching and thereby a decrease in the nutrients of the soil

high pH soil

pH created by compounds being bound and thereby not available for nutrients

Cation Exchange Capacity (CEC)

nutrient holding capacity, based on clay capacity

^clay -> ^cations -> ^ surface for ions to cling -> less leaching

want in between amounts of clay

sand

the coarsest soil, with particles 0.05,2.0 mm in diameter.

silt

A mixture of rich soil and tiny rocks

0.002-0.05 mm

clay

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

physical properties of soil

texture

permeability

chemical properties of soil

cation exchange capacity

base saturation

base saturation

the proportion of soil bases to soil acids, expressed as a percentage

biological properties of soil

microorganisms, detrivores

soil texture pyramid

Used to determine soil properties.

impacts of acid rain on soil

impacts:

1. changes soil chemistry (depends on parent material, decreased nutrient cycling)

2. inherent ecosystem sensitivity (toxic for roots bc locks phosphate, decreases microorganisms, susceptible to virus, fungi, and pests)

PFA

syntheic chemicals called "forever chemicals" due to their non-reactive nature

not well regulated, in many common products, accumulates in lungs, watersheds, and inhibits immune response

Values in Earth's Atmosphere

Values:

1. contains O2, vital for cellular respiration

2. absorbs solar radiation

3. moderates climate

4. transports and recycles water and nutrients

air pressure at sea level

14.7 psi

decreases exponentially from sea level

Layers of the Atomosphere

exosphere, thermosphere, mesosphere, stratosphere, troposphere

relative temperature change in troposphere

decrease due to rising altitude creating a father distance from the surface radiation and decreased pressure

relative temperature change in stratosphere

increase, ozone absorbs and reradiates energy

relative temperature change in mesosphere

decrease, density of gas mol decreases leaving fewer mol absorb sun energy

relative temperature change in thermosphere

increase, solar radiation initially gets absorbed in it's highest quantity, feels cold bc not a lot of particles

Troposphere

the densest and thinnest layer of the atmosphere

factors that increase soil nutrients

organic matter

humus

decomposer activity

clay

bases

factors that decrease soil nutrients

acids leach pos. charge nutrients

excessive rain

excessive farming

topsoil erosion

factors that increase water retention

aerated soil (bio activity)

compost/humus/organic matter

clay content

root structure

factors that decrease water retention

compaction

topsoil erosion

sand

root loss

why does the ozone never drop though it is more dense than the contents of the troposphere?

ozone molecules are constantly breaking down and reforming

major gases present in earth's atmosphere

nitrogen

oxygen

argon

water vapor

CO2

relative abundance of nitrogen

78%

relative abundance of oxygen

21%

relative abundance of argon

.93%

relative abundance of water vapor

.4%

relative abundance of CO2

.04%

climate associated with low pressure

high relative temperatures and high relative precipitation

in which direction does wind flow on a pressure gradient?

high -> low

water vapor capacity

warm air has a higher capacity for water vapor than cold air

adiabatic cooling

the cooling effect of reduced pressure on air as it rises higher in the atmosphere and expands

adiabatic heating

the heating effect of increased pressure on air as it sinks toward the surface of Earth and decreases in volume

latent heat release

the release of energy when water vapor in the atmosphere condenses into liquid water

global wind pattern causes

1. less dense air rises

2. water vapor capacity increases directly with temperature

3. adiabatic heating/cooling

4. latent heat release

Hadley Cell

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

Ferrel Cell

Cell that moves air form 30 degrees to 60 degrees latitude

Polar Cell

Cells of air circulation occurring between 60 degrees north and south and each pole.

tropical convergence

rising motion and storms (near equator)

horse latitudes

a belt of calm air and sea occurring in both the northern and southern hemispheres between the trade winds and the westerlies @ approx 30˚

polar front

boundary at which cold polar air meets the warmer air of the middle latitudes

trade winds

Prevailing winds that blow northeast from 30 degrees north latitude to the equator and that blow southeast from 30 degrees south latitude to the equator

westerlies

Dominant winds of the mid-latitudes. These winds move from the subtropical highs to the subpolar lows from west to east.

Coriolis effect

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

The degree of tilt on earths axis

23.5 degrees

cause of seasons

The tilt of the Earth's axis

weather

short-term atmospheric conditions at a place and time as regards heat, dryness, sunshine, wind, rain, etc.

climate

long-term atmosphere conditions, the average weather conditions in an area over a long period of time

gyre

A large-scale pattern of water circulation that moves clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere

Thermalhaline circulation

"conveyer belt" of ocean patterns throughout oceans due to rising and falling of water due to temperature, driven by local arctic ice cooling

oceanic upwelling

upward movement of ocean water mixing it

more cool and nutrient rich water comes from bottom

supports organisms at top of welling

areas of upwelling

1. far from shore surface currents move apart, drawing from deeper depths

2. western coasts where wind blows along surface pushing water away from land, drawing water up

downwelling

downwards movement of O2 rich ocean water

supports organisms at bottom of ocean

topographic features

structures formed on surface that can change local climate

ex: andes mountains

leeward side of a mountain

Dry and warm due to compression

Windward side of a mountain

Cool and moist due to expansion

ENSO

El Niño Southern Oscillation, see-sawing of air pressure over the S. Pacific

due to shifts in trade winds