Download The Dynamic Earth

The Dynamic Earth
Chapter 3
Environmental Science
Earth
Integrated system

Rock
• Geosphere

Air
• Atmosphere

Water
• Hydrosphere

Living things
• Biosphere
Geosphere


The solid part of the Earth including
all rock, soils, sediments on the
surface
Scientists use seismic waves to study
the geosphere.
• Like tapping a melon
Composition of the Geosphere

Crust
• Thin layer – less than 1% of Earth


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Oceans
Continents
Mantle
• Made of rock
• 64% of the Earth

Core
• Hot, dense rocks of nickel and iron
• 35% of the Earth
Structure of the Geosphere

Five layers based on physical properties
• Lithosphere

Includes crust and upper part of mantle
• Asthenosphere

Rocks in the mantle that allow continents to move
above it
• Mesosphere

Lower layer of the mantle
• Outer core

Dense, liquid layer
• Inner core

Solid rock layer
Tectonic Plates
• Pieces of the lithosphere that continents
sit on
• Glide on asthenosphere like ice on a
pond
• Figure 4 on page 62
• Plate boundaries are where activity
occurs & mountain ridges form
Earthquakes

Occur at a fault
• A break in the Earth’s crust where they
slide against each other.

Richter Scale
• Measures magnitude (0-10)

The amount of energy released by an
earthquake
Volcanoes


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A mountain built from magma that rises to
the Earth’s surface
The hot ash, dust and gases can pollute
the environment
A volcanic eruption can change the Earth’s
climate for several years.
Volcanic ash can mix with water
• Mudflow
Section 1 Assignment


Page 66
Section 1 Review #1-5
Atmosphere


Mixture of gases surrounding the
Earth
Gases are constantly being added
and removed
• Example – Animals release carbon
dioxide and take in oxygen, plants
release oxygen and take in carbon
dioxide
Composition of the Atmosphere

Nitrogen
• 78 % of the atmosphere

Oxygen
• 21 % of the atmosphere

Other Gases
• 1% of the atmosphere
• Includes argon, carbon dioxide,
methane, water vapor

Atmospheric dust
• Particles in the air made mainly of soil

Also includes salt, ash, pollen, bacteria, aerosols
Layers of the Atmosphere

Troposphere
• Closest layer to the Earth’s surface
• Almost all weather occurs here

Stratosphere
• Almost all ozone (made of 3 oxygen
atoms) is located here
• Ozone absorbs UV radiation
Layers of the Atmosphere

Mesosphere
• Coldest layer

Thermosphere
• Layer located furthest from Earth’s
surface
• Temperatures above 2000°C
• Nitrogen and oxygen ions absorb X-rays
and gamma rays
Energy in the Atmosphere

Energy transferred from the sun in
three ways
• Radiation

Transfer of energy from space to
atmosphere
• Conduction

Flow of heat from warmer object to colder
object
• Convection

Transfer of heat through air currents
Heating the Atmosphere



About half the energy from the sun
reaches the Earth’s surface.
The rest is absorbed by clouds, dust
or gases.
Dark-colored objects absorb more
energy than light-colored objects.
Quick Lab

Page 70

Answer the following questions:
• By what mechanism is energy being
transferred to the beakers? Explain
your answer.
• Make a line graph with the results of the
experiment.
• Page 72 – Section 2 Review #6
Answer with a paragraph
Greenhouse Effect
1.
2.
3.
4.
Sunlight enters the atmosphere and
heats the Earth’s surface
The heat is radiated back into the
atmosphere
Heat is absorbed by gases in the
atmosphere
Heat is then radiated back towards
the Earth’s surface.
** Earth would be too cold to survive without
the greenhouse effect.
Greenhouse Gases

Gases that trap and radiate heat
• Water Vapor
• Carbon dioxide
• Methane
• Nitrous oxide
Quiz

Information from Section 1 & 2
Hydrosphere


Any water on or near the Earth’s
surface
Water cycle
• Evaporation
• Condensation
• Precipitation

Oceans
• Pacific, Atlantic, Indian, Arctic
Ocean Water

Salinity
• Concentration of all the salts in ocean
water
• Salinity varies depending on
evaporation and precipitation


Surface water is warm, deeper is
cold due to no sunlight
Oceans absorb heat from the sun
which helps to regulate the
temperature in the atmosphere.
Layers of the Ocean

The layers are called temperature
zones.
• Surface Zone

Warm water (heated from the sunlight)
• Thermocline
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Temperature falls rapidly with depth
Cold water begins in this layer
• Deep Zone
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Bottom of the ocean
Temp around 2°C
Ocean Currents

Surface currents
• Streamlike movements at the surface
• Created by the wind

Deep currents
• Streamlike movements near the ocean
floor
• Flows very slowly towards the equator
Fresh Water

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Only about 3% of all water
River system

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Main river
Tributaries
Land that drains into the river
Groundwater
• Collects underground
• Used for human and agricultural needs
• Aquifers

Rock layers underground that stores water
Biosphere


Narrow layer on Earth’s surface that
supports life
Life on Earth exists due to two
factors
• Water is continually recycled
• Sunlight is readily available

Includes the following:
• Upper part of geosphere
• Most of the hydrosphere
• Lower part of atmosphere
Energy Flow

Closed system
• Energy enters as sunlight
• Matter does not enter

Plants use the sunlight to make their own food
• Earth is considered mainly a closed system

Open system
• Both energy and matter enter

Early years of the Earth when matter was
added through collisions of comets and
meteorites with our planet
Section 3 Review
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Page 81
# 1-6
Chapter Review
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Page 83-85
#6-19, 21, 24-25, 27, 32-33, 34