Chapter 3:The Dynamic Earth
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Transcript of Chapter 3:The Dynamic Earth
Chapter 3:The Dynamic Earth
31. The Geosphere3.2 The Atmosphere
3.3 The Hydrosphere and Biospherep.58-83
Key Terms• Geosphere• Crust• Mantle• Core• Lithosphere• Asthenosphere• Tectonic plate• Erosion• Atmosphere• Troposphere• Stratosphere• Ozone
• Radiation• Conduction • Convention• Greenhouse effect• Water cycle• Evaporation• Condensation• Precipitation• Salinity• Fresh water• Biosphere• Closed system• Open system
3.1 The Geosphere• Describe the composition and structure of the
Earth• Describe the Earth’s tectonic plates• Explain the main cause of earthquakes and their
effects• Identify the relationship between volcanic
eruptions and climate change• Describe how wind and water alter the Earth’s
surface
The Earth as a SystemWhat are the conditions that allow us to survive
on a constantly changing planet?The earth is divide into 4 parts
1. Geosphere (rock)2. Atmosphere (air)3. Hydrosphere (water)4. Biosphere (living things)http://www.youtube.com/watch?v=uG3ql0vLioU
Geosphere• The solid part of the Earth that consists of all
rock, soils and sediments on Earth’s Surface• Most is located in interior • http://volcano.oregonstate.edu/vwdocs/vwlessons/lessons/Earths_layers/Earths_layers1.html
Discovering Earth’s Interior• Very difficult to study – we have only looked at 12km deep • Seismic waves to study Earth’s Interior (waves travel differently in physical
layers)Composition of Earth-
http://www.youtube.com/watch?v=_iUfi8XqEos&feature=related1. Crust- think outer layer, light elements, less than 1% of planet’s mass2. Mantle 64% mass of Earth, 2,900km thick, rock medium density, iron
rich layer3. Core densest element radius of 3,400km, hot nickel and iron center of
EarthBill Nye-
http://www.youtube.com/watch?v=MucQmSIKElU&feature=endscreen&NR=1 (23mins)
Composition of Earth-3 layers1. Crust- think outer layer, light elements, less
than 1% of planet’s mass, 5-8km thick beneath the oceans and 20-70km beneath the continents
2. Mantle- layer under crust, makes up 64% of mass, 2,900km thick, made of rock, medium dense
3. Core- innermost layer, densest elements, radius of 3,400 km
The Structure of the Earth
5 layers- http://video.about.com/geography/The-Four-Earth-Spheres.htm
1. Lithosphere2. Asthenosphere3. Mesosphere4. Outer Core5. Inner Core
Lithosphere- stone• 15-300 km thick• Cool rigid• Outermost layer of Earth• Crust and uppermost part of mantle• Divided into huge pieces called plate tectonic • Both continental and oceanic crust
Asthenosphere• 250 km thick• Solid plastic layer of mantle between the
mesosphere and the lithospehre• Made of mantle rock that flows very slowly,
allows for plates to move on top of it
Mesosphere• 2,550 km thick• Middle sphere• Lower layer of the mantle between the
asthenosphere and the outer core
Outer core• 2,200 km thick• Outer shell of Earth’s core• Made of liquid nickel and iron
Inner Core• 1,228 km radius• Spere of solid nickel and iron at the center of
the Earth
Thicknesses and density
Plate Tectonics• Glide across the underlying asthenosphere like ice on a pond• Continents are located on them and move with them• Pacific, North American, South American, African, Eurasian, and Antarctic
plates• Plate boundaries- this movement may cause mountains, earthquakes,
volcanoes erupt• Plate Tectonics and Mountain Building- Himalaya Mountains (Asia and
India plates collided 50mya)
• http://www.ucmp.berkeley.edu/geology/tectonics.htm• http://www.youtube.com/watch?v=1-HwPR_4mP4 (7mins)• NGO- 50minshttp://www.youtube.com/watch?v=KCSJNBMOjJs&feature=relatedBill- 23mins
https://www.youtube.com/watch?v=2hKssFQdZ0k&feature=related
Earthquakes• Fault- break in Earth’s crust preventing it from
sliding• When it breaks and creates vibrations in crusts
creates earthquakes• Occur all the time most are too small to feel• Richter scale- quantify the amount of energy
reassessed by an earthquake or its magnitude• Smallest magnitude that can be felt is 2.0• Largest recorded 9.5• Earthquakes of 7 or greater cause widespread damage
Where do they occur?• Take place at the boundaries due to the stress level• San Andreas Fault along California (N. American
plate and Pacific plate are slipping)• We cannot predict when they will occur but rather
the likely hood of where they can occur• High risk areas we build bridges and buildings
slightly flexible so they can sway when the ground moves
• http://earthquakestoday.info/
Japan's Tsunami - How it Happened 2011
• http://www.youtube.com/watch?v=24A8UwpYSs8&feature=related
Volcanoes• Mountains/ islands built from magma, melted
rock, that comes from the Earth’s core• Can occur on land or under the sea• Most active areas is around the pacific Ocean
plate boundaries• https://www.youtube.com/watch?v=NBPwwt0HuVo
Local Effects of Volcanic Eruptions• Loss of human life• Clouds of hot ash, dust, gases travel down at
speed of 200km/hr killing everything in its path
• Can mix with water can create a mudslide• Destroy buildings, bury crops, damage engines
of vehicles• Breathing difficulties
Global Effects of Volcanic EruptionsGlobal impact: https://www.youtube.com/watch?v=TghGWlVN31chttps://www.youtube.com/watch?v=k8mAtY-7n-o
• Mt St Helen- change Earth’s climate for several years• Ash and gases travel into the atmosphere reducing
sunlight decreasing global temperatures for several years
• Top 10- https://www.youtube.com/watch?v=4aYQixhdWY4&feature=fvwrel• Billl Nye• https://www.youtube.com/watch?v=gOc04z8jHaM• https://www.youtube.com/watch?v=MucQmSIKElU&feature=related (23mins)
Erosion• The removal and transport of surface material • Water Erosion- rivers create deep gorges or
oceans waves erode coastlines• Wind Erosion- area where plants are limited
(beaches and deserts) sandstone vs granite can erode more quickly
https://www.youtube.com/watch?v=G5Rp9MJJGCUBill- https://www.youtube.com/watch?v=HjVSiuj7Lxk&feature=related
3.2 Atmosphere• Describe the composition of the Earth’s
Atmosphere• Describe the layers of the Earth’s atmosphere• Explain 3 mechanisms of heat transfer in
Earth’s atmosphere• Explain the greenhouse effect
Atmosphere• Mixture of gases found in first 30km above the
Earth’s surface
Composition of the Atmosphere• Nitrogen 78%• Oxygen – 21%• Other -1 % (argon, carbon dioxide, methane, water
vapor)• Tiny solid particles or dust (soil, salt, ash, skin, hair
clothing, pollen, bacteria, viruses, aerosols)• Air pressure- due to the gravity, more dense closer
to earth, difficult to breath at higher elevations• http://www.youtube.com/watch?v=jmQ8FWnM0fA
Layers of the Atmosphere1. Troposphere2. Stratosphere3. Mesosphere4. Thermosphere
Troposphere-a. layer closes to the Earth’s surface to 18km aboveb. weather occurs in this layerc. densest layerd. temperature decreases as altitude increases
Stratosphere-• Above the troposphere• Extends from 18km to altitude of 50km• Temperatures rise as altitude increases in the
stratosphere, because the ozone absorbs the suns UV energy and warms the air
• Ozone- O3- molecule that is made up of 3 oxygen atoms
• Reduced the amount of UV that reaches the Earth
Mesosphere• Layer above the stratosphere• Extended to an altitude of 80km• Coldest layer as low as -93’C
Thermosphere• Farthest from the Earth• Nitrogen and oxygen absorb solar radiation-
temperatures have been measured above 2,000’C• Would not feel hot to us because this layer is so thin
that air particles rarely collide – little heat is transferred
• Lower level is called ionosphere – it absorbs X and gamma rays, causing the atoms to be electrically charged (ions)
• Ions can radiate energy as light- Aurora Borealis or Northern Lights (North and South poles)
Energy in the Atmosphere• Energy is neither created or destroyed
transferred and transformed1. Radiation- transfer of energy across a space (fire,
sunlight)2. Conduction- flow of heat from one object to
another3. Convection- air currents (hot air rises)
Heating of the Atmosphere• Solar energy reaches the Earth as electromagnetic
radiation, visible light, infrared radiation, UV light• Only ½ actually reaches the Earth• Most is absorbed or reflected by clouds, gases and dust• Ocean/ lakes and land radiate the energy back into the
atmosphere• 50% absorbed by Earth’s Surface• 25% scattered and reflected by clouds and air• 20% absorbed by ozone, clouds and gases• 5% reflected by Earth surface
The Movement of Energy in the Atmosphere
• Convection Currents- movement of the air in a circular pattern that are caused by the unequal heating of the Atmosphere
• Cold air sinks and hot air rises
The Greenhouse Effect• Gases trap heat near the Earth• Like heat being trapped into a car on a hot
day, the glass window would be the atmosphere
• This allows for the Earth to be warm, if it did not occur Earth would be too cold for life
3 mins- http://www.youtube.com/watch?v=ZzCA60WnoMkDiscovery Channel - Global Warming, What You Need To Know, with Tom Brokaw80mins- http://www.youtube.com/watch?v=xcVwLrAavyA&feature=related
3.1The Hydrosphere and Biosphere
• Name 3 major processes in the water cycle• Describe the properties of ocean water• Describe the 2 types of ocean currents• Explain how the ocean regulates Earth’s
Temperature• Discuss the factors that confine life to the
biosphere• Explain the difference between open and closed
systems
Hydrosphere• Makes up all of the water on the Earth’s
surface• Most is found in the oceans (3/4 globe)• Atmosphere, land and in soil
Hydrosphere and Water Cycle
• Water cycle- Continuous movement into ht air, land back to water– Evaporation- liquid water is heated by sun and goes
into the atmosphere– Condensation- water vapor cools and forms water
droplets– Precipitation- larger droplets fall from clouds (snow,
sleet, or hail)Bill Nye- (3mins)http://www.youtube.com/watch?v=hehXEYkDq_YRap- http://www.youtube.com/watch?v=i3NeMVBcXXU&feature=fvwrelMagic School Bus- http://www.youtube.com/watch?v=yfLTBJKnEQA
Earth’s Oceans• World Oceans- Arctic, Pacific, Atlantic, Indian• 70% of earth surface• Regulates Planet’s environment• High salt concentrations (salinity)( lower where
freshwater or rain runs into it, high in areas where evaporation is high)
• Temperature zones- surface warmed by sun, deep clod no sunlight (surface zone, thermocline- warm and cold weather)
Global Temperature Regulator
• Absorb and store energy from sunlight regulates temperatures in Earth’s Atmosphere
• Ocean absorbs and release more slowly than land does
• If it did not regulate temps conditions would be too extreme for life today
• Can warm land masses near by
Ocean Currents• Surface currents- stream like movements of
water that occur at or near the surface, wind driven and a result from global wind patterns
http://www.youtube.com/watch?v=YCorkyBe66o
• Deep currents- streamlike movements of water that flow very slowly along the ocean floor (Antarctic Bottom Water)
http://www.youtube.com/watch?v=XVZujRMGZzs
Bill Nye- http://www.youtube.com/watch?v=4_wLatK7sXghttp://www.youtube.com/watch?v=w_8mw-1HYFg
Fresh water• 3% of Earth’s water• Most is locked in icecaps and glaciers• Lakes, rivers, streams, ground water, wetlands,
and atmosphere• River systems- network of streams that drains
an area of land including its tributaries (small that flow into large ones)
• Mississippi River system 40%
Ground water• Rain and melting snow run off the land
collected into the ground• 1% of all of Earth’s Water• Aquifers- rock layer that stores and allows the
flow of ground water• Recharge zone- where water enters an aquifer
Biosphere• Part of Earth were life exists • Think layer at Earth’s surface down to the
bottom of the oceanhttp://www.youtube.com/watch?v=RmifaYcLPik&feature=related
Biosphere• If the Earth was an apple- it would be the skin• Uppermost part of the geosphere, most of
hydrosphere, lower part of atmosphere• 11km into the ocean and 9km into the
atmosphereLife requires:
• liquid water• Temps between 10-40’c • Source of energy
Energy Flow in the Biosphere• Sun light main source of energy• 4 biogeochemical cycle ( recycling of once
living organisms to be put back into the Earth’s resources)– Closed system- Earth mostly closed with respect
to matter, Eden Project– Open system- sun/ energy, energy comes in from
the sun and lost as heat
Webquest:• http://www.learner.org/interactives/dynamice
arth/structure.html
BBC- Power of the Planet
Atmosphere • http://www.youtube.com/watch?v=J5ViCNJAk
Hg&feature=endscreen&NR=1Earth• http://www.youtube.com/watch?v=a_pzxz71j
DM&feature=fvwrelice• http://www.youtube.com/watch?v=H0Maf03
wGvE&feature=relmfu