APES- Unit 4

Core

Innermost zone, composed mainly of iron/nickel. It has a liquid outer layer, a solid inner layer, and it’s radioactive. It’s very dense.

Mantle

Contains molten rock that circulates in convection.

Asthenosphere

Outer part of the mantle. Semi-molten ductile rock.

Lithosphere

Composed of the outermost part of the mantle (but above asthenosphere) and the crust. It’s brittle, and is the tectonic plates.

Crust

Outermost layer of the lithosphere on which we live.

Divergent boundaries

Plates move apart due to convection cycles under the lithosphere.

As the plates move apart, new magma from underneath fills in the gap and cools to form new rock.

This type of boundary generally occurs under oceans.

Convergent boundaries

Two plates collide.

If plate density is equal (ocean-ocean or continent-continent), both plates push upwards and form mountains.

If plate density is unequal (ocean-continent) then the more dense plate subducts under the other one.

Oceanic Plates

Which is denser? Oceanic or Continental plates?

Subduction

When one plate slips under the other one

Transform Boundaries

Two plates move sideways past each other.

Fault

The area where a transform boundary is.

Epicenter

Where an earthquake occurred on the surface

Focus

Where an earthquake actually occurred under the crust

Ring of Fire

The locations of volcanoes and earthquakes form a circle of seismic activity.

Hotspots

Areas where the lithosphere thins, magma can seep through and cause volcanoes, etc.

Nitrogen, Oxygen, Argon, Water Vapor, Carbon Dioxide

Gases of Earth

Troposphere

Densest layer at the bottom. Nitrogen, Oxygen, water vapor. Weather occurs here, convection of fluids. Temperature decreases with height, (-62 F at top!)

Stratosphere

Absorbs UV and converts it to infrared (heat). Ozone layer is a part of this layer.

Ozone Layer

The lower layer of the stratosphere. Absorbs most of UV-B and all of UV-C (UV-A is good for you! (Vitamin D)) from the sun, critical protection for our planet. Colder than upper strat.

Mesosphere

Comets burn up here. The middle layer.

Thermosphere

Blocks harmful X-rays/UV radiation. Becomes really hot because of this! Contains northern lights (due to charged gas molecules that absorb sunlight and glow).

Exosphere

The outermost layer, and the least dense. Satellites and the orbit of earth.

Air Density

Mass of molecules in air at a given volume. Determines movement.

Less

Hotter air is _____ dense.

Capacity to contain water vapor

Hot air can contain more. When humid air cools, saturation point lowers and precipitation ensues

Saturation Point

Maximum water in the air at a given time

Adiabatic cooling

When hot air rises, the pressure on it decreases, so even as it’s getting cooler, it expands, and becomes even less dense, so it rises even higher.

Latent heat release

When water vapor condenses, it releases heat. B/c of this, when water condenses, the air rises.

Coriolis effect

Because of earth’s rotation, winds moving north or south are deflected east or west.

(Deflected west when winds are moving towards equator. Deflected east when winds are moving towards higher lats. Due to different speeds at different lats.)

East

The earth rotates towards the ____

East Trade Winds

These winds are going towards the equator. So, they’re displaced to the west.

Where they come from

Winds are named based on: (Where they come from, or where they’re going)?

Westerlies

These winds are heading to the poles. So they’re displaced to the East.

Easterlies/Polar Winds

These winds move from the poles to the mid-lats, so they’re displaced to the west.

Doldrums

Areas in-between cells with no winds, often on the main latitudes (0, 30, 60, 90)

The most intense sunlight hitting the equator

Global wind patterns primarily result from:

Watershed

All of the land in a given landscape that drains into a particular stream, river, lake, or wetland

Mountains, precipitation, river location

Wetland are determined by:

Vegetation, soil composition, and slope

3 factors that play a large role in how watersheds drain:

Human impacts on watersheds:

• Pollution (sewage, animal manure, fertilizer spill, pesticides, pharmaceutical drugs)

• Erosion, sediments clouding water

• Agriculture (runs nutrients and aquifers dry)

• Clear cutting (quickens erosion)

• Urbanization (more prone to flooding)

• Dams (Slow water flow, so there’s rich minerals on one side and poor minerals on the other side)

• Mining (Pollutes water, speeds up erosion)

Eutrophication

Too many nutrients, so the ecosystem is out of balance

Solutions for watersheds

• Cover crops

• Riparian buffers (basically cover crops but for wetlands)

• Animal manure management (use as compost instead)

• Septic tank upgrades

• Biological nutrient removal

• Enhanced nutrient removal

Insolation

Incoming solar radiation

Watts per square meter

Insolation measured in:

Angle and surface area

2 factors that influence solar intensity:

Angle

It takes the sun’s rays longer to travel to the mid-lats and polar regions than to the equator, and heat is lost the more distance is traveled.

March/September Equinox

Sunlight strikes the equator directly. All areas of earth get 12 hours of daylight.

June Solstice

The sun is directly above the tropic of Cancer. The Northern Hemisphere has the most daylight hours than any other day of the year. The S hem experiences the least daylight hours.

December Solstice

The sun is directly above the tropic of Capricorn. The Southern Hemisphere has the most daylight hours than any other day of the year. The N hem experiences the least daylight hours.

Albedo

The percentage of incoming sunlight that is reflected from a surface

Less heating

Higher albedo =

White

Which has a higher albedo, white or black?

Rain Shadows

Humid wind from the ocean meets mountains. It’s forced up. It’s forced to cool, so it precipitates. Because of latent heat release, it keeps rising and precipitating until its fully dry. When the air finally makes it over the mountain, it’s dry. Leaves arid land on the other side of the mountain.

Windward side

The side of the mountain humid air hits. The climate here is humid and lush.

Leeward side

The side of the mountain the air does not hit. The climate here is dry and arid.

Gyres

Large circular patterns of water currents due to the slight slope of the water near the equator (due to expansion of particles in higher heat) and trade winds. Clockwise in N hem, Counterclockwise in S

→

Clockwise:

Upwelling Zones

Zones where cold water moves to the surface to replace a diverging surface current. It brings nutrients with it, creating productive ecosystems.

El Nino Southern Oscillation

Trade winds push water East to West. Every 3-7 years, the winds weaken, and this occurs, and the water moves West to East. This can lead to starvation due to lack of typical upwellings. (Positive Feedback Loop)

Thermohaline Circulation

Warm salty water moves to the cold N Atlantic. There, some evaporates and some sinks low, and due to the warm currents, the deep current travels past Antarctica and to the Pacific, where it resurfaces (at upwelling zones) and travels as a warm surface current to the Gulf of Mexico, and back to the cold N Atlantic.

La Nina

Trade winds weaken, but this time, instead of the water reversing direction, it combats the weakened trade winds by moving even more extremely from East to West. All the normal effects are amplified instead of reversed. (Negative feedback loop)