Download The Geosphere

The Geosphere!
Earth
• Seismic waves are used to study the interior
– Detect changes in the material as they travel
through
• Seismologist measure the change in speed
and direction of the waves
• Earth has 3 parts
– Crust
– Mantle
– Core
Layers of the Earth
• Crust
– Outer layer
– Thinnest layer
– Only 1% of the planets mass
• Mantle
– Beneath the Crust
– Made of rocks with medium density
– 64% of the planets mass
• Core
– Innermost layer
– Composed of the most dense elements
Structure of the Earth
• Lithosphere
– Cool rigid layer
– Includes crust and upper mantle
– Divided into tectonic plates
• Asthenosphere
– Solid layer of mantle
– Made of rock that flows slowly
– Allows tectonic plates to move
Structure of the Earth
• Mesosphere
– Lower part of the mantle
• Outer core
– Outer shell of earths core
– Made of liquid nickel and iron
• Inner core
– Made of solid nickel and iron
Plate Tectonics
• Tectonic plates glide on top of the
asthenosphere
• Major plates
– North American
– South American
– African
– Pacific
– Eurasian
– Antarctic
Plate Boundaries
• Types of Movement
– Collide
– Separate
– Slide past one another
• Can form
– Mountains
– Earthquakes
– Volcanoes
Earthquakes
• Fault: Break in earths crust where blocks of
crust slide past one another
• Richter Scale: Measures earthquakes
magnitude (energy)
Earthquakes
• Occur mostly at or near tectonic plates due to
the stress on the plates
• Many occur along
San Andreas Fault
Earthquake Hazard
• Area’s earthquake hazard level determined by
past and present activity
• Earthquake resistant buildings are slightly
flexible
Volcanoes
• A mountain built from magma (melted rock)
that rises from Earths interior
– Usually near plate division or collision
– Can be on land or under water
– If under water it may lead to island formation
Effects of Eruption
• Clouds of hot ash, dust and gasses flow down
– Cause mud flow
– Ash covers crops, damages engines, cause
breathing difficulties
• Causes climate changes
Erosion
• Erosion: Removal and transport of surface
materials
• Water erosion
– Rivers: Create deep gouges through mountains
– Oceans: Water continually beat against the land
surface
• Wind erosion
– Plants root soil, if no plants soil will blow away
LAND
Chapter 14
How we use land
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Farming
Mining
Building (cities and highways)
Recreation
• Land cover: What you find on a patch of land
Types of Land Cover
• Forest
• Field of grain
• Parking lot
• Most land provides one or more resources
used by humans
Urban vs Rural
• Urban Land: Land that is covered mainly with
buildings and roads
• Rural Land: Land that contains relatively few
people and large areas of open space
• Land use in the united states
– 28% farmland
– 6% Urban
– 26% Pasture
-- 20% Cropland
-- 13% Parks
-- 7% Other
Industrial Revolution Impact
• Due to the industrial revolution, people
started going from rural to urban areas
– Machinery made it more possible for less people
to have to work on the farm
– More transportation to go farther with the
products
– More jobs available in cities
• The result…
– Urban areas took over more land
The Connection
• Rural areas produce resources that people
depend on
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Clean water
Fertile soil
Crops
Trees
Oxygen
• Ecosystem services: Resources produced by
natural and artificial ecosystems
Rural Land
• The area of rural land that is needed in order
to support a person depends on
– Climate
– How they live
– How the resources are used
• Example: In a wet climate, most agriculture
depends on rain for irrigation and not lakes
and rivers.
Land Use: Caldwell, NJ
Green(private)
13%
Green(community)
24%
Shopping
13%
Water
2%
Housing
9%
Water
Housing
Pavement
Pavement
39%
Shopping
Green(community)
Green(private)
Urbanization
• Urbanization: The movement of people from
rural areas to cities
• Why would this happen????
• People leave rural areas for more plentiful and
better paying jobs in towns and cities
Metropolitan Areas
• Small towns that have grown together to form
larger urban areas
• Examples
– Washington, D.C.- Baltimore
– Denver-Boulder
– Manhattan-Queens-Bronx
Urban Area Growth
• If an urban area grows slowly…
– Roads and public transportation are designed to
handle the growth (Free flowing traffic)
– Buildings, roads, parking lots are mixed with green
areas
• If urban areas grow to fast,
– It can overwhelm the infrastructure and lead to
traffic jams, insufficient housing, and pollution
Infrastructure
• This is all of the things that a society builds for public
use
• It can include
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Roads
Sewers
Railroads
Bridges
Canals
Schools
Fire stations
Hospitals
Libraries
Power lines
Urban Problems
• Urban crisis: When more people live in a city
than its infrastructure can support
• Urban sprawl: Rapid expansion of the city into
the countryside around the city
– This results in suburbs
Suburbs
• Built on land that was previously used for food
production
• Most Americans live in suburbs compared to
countryside and cities.
Marginal Lands
• Land that is poorly suited for building
– As cities grew, suburbs are built on these marginal
lands
• An example is Los Angeles
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Built on a basin
The cities go into mountains
This causes landslides
It becomes difficult to repair the damage
Urbanization Impacts
• Cities generate and trap more heat
– The heat is generated through the infrastructure
that makes the cities run
– Roads absorb heat
• Result of more heat: Heat Island
– The increased temperature in the city
Heat Islands
• Heat islands can cause changes in local
weather
• Hot air rises over a city, cools as it rises,
eventually producing rain clouds…
– So there is increased rainfall
• To help heat islands
– Plant trees for shade
– Install rooftops that reflect instead of retain heat
Urban Planning
• Land-use planning: Determining in advance
how the land will be used
– Where to build houses, businesses, factories
– Where the land will be protected
– Where the land for recreation will be
– The best locations for shopping malls, sewers,
electrical lines, ect.
The problem…
• Land-use models are
– Complex
– Controversial
• They require detailed reports of information
addressing the impacts
• The public can comment
• Can be disagreed upon by other people
(developers, governments, businesses)
Transportation in Cities
• Most cities are difficult to travel in without a
car
• Most American cities are built after the
invention of cars and cover large areas
• European cities are built before the invention
of cars and have narrow compact roads
Mass Transit
• Use busses and trains to move many people at
one time
• Save energy
• Reduce highway traffic
• Reduce air pollution
• Limit loss of land to roadways and parking lots
Open Space in Urban Areas
• Set aside for scenic and recreational enjoyment
– Parks, gardens, bike trails
• Greenbelts: provide important ecological services
• Benefits:
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Absorb carbon dioxide
Produce oxygen
Filter out pollutants
Absorb rainwater and runoff
Spaces for exercise and relaxation
WASTE
Waste
• Waste: Any discarded solid material
– Includes everything from junk mail to coffee
grinds and even cars
• Many towns are running out of room to get rid
of waste
Waste Problems
• Problems are caused by
– The amount of solid waste
– The type of waste
• Biodegradable: Can be broken down by natural
processes
– Paper, cotton, leather
• Nonbiodegradable: Cannot be broken down by
natural processes
– Polyester, nylon, plastic
Waste
• Plastic is made from petroleum and natural
gas
– Cannot be broken down by natural processes
• Types of Waste
– Municipal waste
– Manufacturing waste
– Mining waste
Waste
• Municipal Waste: What we throw out on a
day to day basis
– 2% of solid waste
– Could fill a convoy of garbage trucks that would
stretch around the Earth
– Increases faster than all the other wastes combine
Waste
• Manufacturing waste: computers, audio
equipment, printers
– Scrap metal, plastics, paper, sludge, ash
• Mining waste: Waste rock, minerals, topsoil
– Rock and minerals left over from excavating
– Left dumped in oceans or used to refill mines
Waste Management
• Most municipal waste in the US is sent to
landfills
• Some waste is incinerated (burned)
• Some is recycled
• Landfill: Permanent waste-disposal facility
where wastes are put into the ground and
covered with soil or plastic
– 50% of municipal and manufacturing solids end up
here
Landfill Problems
• Leachate: Liquid that has passed through
compacted solid waste in a landfill and
contains chemicals
• Methane: Produced by organic waste
decomposing where there is no oxygen
– Highly flammable
How to Prevent this
• Landfills must be lined with clay and plastic
liners
• Must have systems for collecting and treating
leachate
• The EPA suggests that the active landfills in 20
states will be filled to capacity within 10 years
Incinerators
• Incinerated materials can take up less space…
but can also produce toxic gas
• Must have special air pollution control devices
which do not remove all toxins
Solid Waste
• Source Reduction: Any change in design,
manufacture, purchase, or use of materials or
products to reduce their amount of toxicity
before they become municipal solid waste
Buying Less
• If you buy products that have
– Less packing
– Last longer
– Can be reused
• Then the manufacturer will create more of
those products… SUPPLY AND DEMAND
• These products could save resources and
reduce waste disposal problems
Recycling
• Reusing materials or recovering valuable
materials from waste
– Saves energy, water, and other resources
• 70% less energy to make paper from recycled
paper then from trees
Compost
• People put fruit and vegetable scraps in
compost piles
• Warm, moist, dark conditions allow bacteria
to grow and break down the waste rapidly
• The result is dark brown crumbly material
used to spread on gardens and fields to enrich
the soil (Lots of nutrients)
Problem with Recycling
• Juice boxes are made from cardboard, foil, and
plastic
• Its hard to recycle because you can’t separate the
3 items
• More things could be recycled if they were made
of
• Glass
• Cardboard
• Aluminum
Degradable Plastics
• Photodegradable: When left in the sun for
many weeks it becomes weak and brittle and
breaks apart
• Green Plastic: Made from sugars from plants
and chemicals that make up the plastic
– Uses less fossil fuels
– When this plastic is buried the bacteria in the soil
eat the plant sugars and leave the weakened
plastic which eventually breaks down