Earth’s Spheres Atmosphere: the envelope of gases that surrounds the Earth

Earth’s SpheresEarth’s SpheresAtmosphereAtmosphere:: the envelope of the envelope of gases that surrounds the gases that surrounds the Earth.Earth.

Earth’s SpheresEarth’s Spheres

HydrosphereHydrosphere: water part of the : water part of the Earth, including surface and Earth, including surface and subsurface water.subsurface water.

HydrosphereHydrosphere

Refers to the Refers to the watery watery part of the part of the Earth.Earth.

Most of the Earth’s water is in Most of the Earth’s water is in oceans oceans but also in lakes, streams but also in lakes, streams rivers, rivers, groundwater and groundwater and glaciersglaciers..


97%97% is is salt salt waterwaterThe remaining 3% is The remaining 3% is freshfresh

water, water, 2/32/3 of the total of the total freshwater is freshwater is frozenfrozen in the ice in the ice caps of the North and South caps of the North and South Poles.Poles.


The hydrosphere also includes The hydrosphere also includes water found in the water found in the atmosphereatmosphere and the amount tied up in the and the amount tied up in the cyclecycle..


Biosphere-Biosphere-Includes all living Includes all living things on Earth things on Earth


LithosphereLithosphere: outer solid shell of the Earth : outer solid shell of the Earth that extends 70 km or more from the crust that extends 70 km or more from the crust and part of the Asthenoshereand part of the Asthenoshere

LithosphereLithosphere Includes the earth’s Includes the earth’s crustcrust and the upper and the upper

mantlemantle.. It is 100 km thickIt is 100 km thickThe lithosphere is broken up into The lithosphere is broken up into platesplates. They . They

can move around can move around independently independently of each of each other.other.

The plates float around on the The plates float around on the asthenosphereasthenosphere, , the liquid portion of the mantle.the liquid portion of the mantle.

Earth’s SpheresEarth’s Spheres AsthenosphereAsthenosphere: partially melted layer of : partially melted layer of

mantle below the lithosphere. This is mantle below the lithosphere. This is responsible for plate tectonic movement.responsible for plate tectonic movement.

1. Crust: 10-65km thick1. Crust: 10-65km thick A) Thickest under theA) Thickest under the

continents.continents. B) Low B) Low density.density. C) Lighter C) Lighter rock.rock. D) SolidD) Solid..

2. Mantle: The upper mantle 2. Mantle: The upper mantle contains magnesium, silicon, and contains magnesium, silicon, and

iron.iron. A) 2900km ~ the A) 2900km ~ the

thickest thickest layer. layer. B) Made up of B) Made up of

heavierheavier rocks. rocks. C) The upper C) The upper

mantle contains mantle contains the Asthenoshere the Asthenoshere which is soft and which is soft and flowing.flowing.

3. Outer Core: the base of the 3. Outer Core: the base of the mantlemantle

A) Liquid A) Liquid iron iron and nickel.and nickel.

B) 2175 kmB) 2175 km

4. Inner Core: solid iron and 4. Inner Core: solid iron and nickel.nickel.

A) A) Spherical Spherical in in shape.shape.

B) 2575 km in B) 2575 km in diameter.diameter.

AtmosphereAtmosphere

The The gaseous gaseous layer, extending from the layer, extending from the surface of the earth to outer surface of the earth to outer spacespace. .

It is made up of a mixture of gases with It is made up of a mixture of gases with some suspended some suspended solidssolids and liquids. and liquids. The most common gases are The most common gases are

Nitrogen Nitrogen 78%78% OxygenOxygen 21% 21% 1% 1% waterwater vapor and others vapor and others

- The earth was NOT structured - The earth was NOT structured like this 4 billion years ago.like this 4 billion years ago.

- According to the - According to the Protoplanet Protoplanet HypothesisHypothesis, the surface of the earth, the surface of the earth

looked like the looked like the moon moon does.does.- The rock throughout the earth - The rock throughout the earth was was same same all the way through.all the way through.

- As the earth heated, - As the earth heated, ironiron and and nickel melted, flowed nickel melted, flowed downwarddownwardtoward the center. On the way it toward the center. On the way it

melted melted lighterlighter materials and materials and forcedforced them upward to the surface.them upward to the surface.

- The lighter rock became solid - The lighter rock became solid and formed the crust.and formed the crust.

Layers of the AtmosphereLayers of the Atmosphere

The atmosphere filters The atmosphere filters ultravioletultraviolet rays and protects rays and protects living things from the sun’s living things from the sun’s harmful UV raysharmful UV rays..

5 Layers of the Atmosphere5 Layers of the Atmosphere

The layers become less The layers become less dense dense (thick)(thick), the farther away from , the farther away from the Earth’s surface you go.the Earth’s surface you go.

TroposphereTroposphere

1. 1. TroposphereTroposphere – surface to 10 km – surface to 10 km (~6 miles) above.(~6 miles) above. Contains Contains mostmost of the gases of the gases The air we breathe is hereThe air we breathe is here Most Most weatherweather occurs here. occurs here.

StratosphereStratosphere

2. Stratosphere2. Stratosphere – 10km-45km (6-28 – 10km-45km (6-28 miles) abovemiles) above The air is very The air is very thinthin here, but here, but windwind

still blows.still blows. AirplanesAirplanes fly in the lowest parts fly in the lowest parts Contains the Contains the ozoneozone layer, which layer, which

protects us from the Sun’s protects us from the Sun’s UV raysUV rays. .

Merge with Outer SpaceMerge with Outer Space

3. 3. MesosphereMesosphere

4. 4. ThermosphereThermosphere

5. 5. ExosphereExosphere

““It’s often said that you cannot get It’s often said that you cannot get something for nothing, but the something for nothing, but the universe may be the ultimate free universe may be the ultimate free lunch.” Alan Guth---physicist lunch.” Alan Guth---physicist

How did the Earth Begin?How did the Earth Begin?

meteroids,asteroids,comets No scientist knows for certain how Earth No scientist knows for certain how Earth

was was formedformed or from what it came. or from what it came. There are a number of There are a number of theoriestheories on the on the

origin of earth.origin of earth. All of these theories must consider the All of these theories must consider the

following scientific facts:following scientific facts:

How did the Earth Begin?How did the Earth Begin?

A. All A. All planetsplanets revolve around the sun in revolve around the sun in the same direction (counter clockwise)the same direction (counter clockwise)

B. The paths or B. The paths or orbitsorbits of planets are all of planets are all nearly nearly circularcircular..

C. Orbits of planets are in nearly the C. Orbits of planets are in nearly the same same planeplane..

D. The D. The sunsun rotates on its axis in almost rotates on its axis in almost the same plane as the the same plane as the planetsplanets

How did Earth Begin?How did Earth Begin?

E. Most planets rotate in the same E. Most planets rotate in the same directiondirection as the sun. as the sun.

F. 6 planets have F. 6 planets have moonsmoons and most and most revolve around the planet as the planet revolve around the planet as the planet does the does the sunsun..

G. The sun’s rate of rotation is G. The sun’s rate of rotation is slowerslower than expected by scientists.than expected by scientists.

The Big 3The Big 3

1. ENCOUNTER HYPOTHESIS1. ENCOUNTER HYPOTHESIS The The SolarSolar system began approximately 5 system began approximately 5

billionbillion years ago with our years ago with our sunsun already in already in existence.existence.

The sun is hanging out when a The sun is hanging out when a starstar or or perhaps a perhaps a cometcomet passes very close to the passes very close to the sun.sun.

ENCOUNTER HYPOTHESISENCOUNTER HYPOTHESIS

A A collisioncollision happens and HUGE amounts of happens and HUGE amounts of gasgas from the sun explode out of it but move in from the sun explode out of it but move in the same the same directiondirection around the sun. around the sun.

After a After a millionmillion years, the gases shrink into years, the gases shrink into ballball shaped bodies.shaped bodies.

The larger ones become The larger ones become planetsplanets and the and the smaller ones become smaller ones become moonsmoons..

The ones that never shrank became The ones that never shrank became cometscomets..

NEBULAR HYPOTHESISNEBULAR HYPOTHESIS

A HUGE cloud of A HUGE cloud of gasgas rotates through space, rotates through space, this cloud is called a this cloud is called a nebularnebular..

The nebula cools and The nebula cools and shrinksshrinks, making it , making it spinspin faster.faster.

The spinning increases causing it to throw off The spinning increases causing it to throw off a a ringring, then another until it has thrown off , then another until it has thrown off ninenine rings.rings.

Each thrown ring becomes a Each thrown ring becomes a planetplanet..

NEBULAR HYPOTHESISNEBULAR HYPOTHESIS

The The cloudcloud at the center shrinks A LOT more. at the center shrinks A LOT more. The shrinking causes The shrinking causes compressioncompression which which causes causes heatingheating and it becomes a fiery HOT and it becomes a fiery HOT starstar..

The sun, The sun, planetsplanets and and moonsmoons are all spinning are all spinning in the same direction as the original in the same direction as the original nebulanebula that they came from.that they came from.

PROTOPLANET HYPOTHESISPROTOPLANET HYPOTHESIS

This is the This is the theorytheory most in favor right now. most in favor right now. The solar system began with a great cloud of The solar system began with a great cloud of

gasgas and and dustdust.. The cloud The cloud shrinksshrinks under the pull of its own under the pull of its own

gravitationalgravitational forceforce.. The material concentrates in the The material concentrates in the centercenter where where

compression causes it to get really compression causes it to get really hothot and it and it forms the sun. forms the sun.


Unlike the Nebular hypothesis, there are no Unlike the Nebular hypothesis, there are no ringsrings..

10%10% of the cloud’s matter forms a single of the cloud’s matter forms a single diskdisk around the sun.around the sun.

Both the disk and the Both the disk and the sunsun rotate slowly. rotate slowly.


GravityGravity within the disk causes material to within the disk causes material to collect in several huge collect in several huge whirlpoolswhirlpools called called eddies.eddies.

Write this on bottom of notes!Write this on bottom of notes! EddiesEddies__beginningbeginning ofof sun sun

formationformationplanetesimalsplanetesimalsprotoplanetsprotoplanetssunsun ignitesignitesplanetsplanets and and moonsmoons

There are some leftoversThere are some leftoverscometscomets, , meteorsmeteors asteroids, planetoids(large asteroids)asteroids, planetoids(large asteroids)

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How does the Earth evolve over How does the Earth evolve over time?time?

There are 3 theories on the evolution of There are 3 theories on the evolution of the universe:the universe:

1. The 1. The BigBig BangBang TheoryTheory Proposed by Le Maitre and Proposed by Le Maitre and GamnlowGamnlow In the beginning…In the beginning… All matter in the All matter in the universeuniverse was concentrated in was concentrated in

an EXTREMELY an EXTREMELY densedense and hot and hot fireballfireball.. 20 billion years ago: a HUGE 20 billion years ago: a HUGE explosionexplosion

occurredoccurred

The Big Bang TheoryThe Big Bang Theory

All that matter was All that matter was brokenbroken into pieces and into pieces and thrown with high thrown with high speedspeed in all directions. in all directions.

Eventually this formed Eventually this formed starsstars and and galaxiesgalaxies and these bodies are STILL moving and these bodies are STILL moving awayaway from each other.from each other.

As the matter As the matter cooledcooled from the explosion, from the explosion, Hydrogen and Hydrogen and HeliumHelium gas formed. gas formed.

1 billion years later, the first 1 billion years later, the first starsstars were were born.born.

2. 2. SteadySteady State Theory State Theory

Proposed by Bondi, Gold and Proposed by Bondi, Gold and HoyleHoyle The theory:The theory: The number of The number of galaxiesgalaxies in the universe is in the universe is

constant and new galaxies are constant and new galaxies are continuouslycontinuously created out of empty space when galaxies created out of empty space when galaxies leave our leave our universeuniverse..

The mass of the universe remains the The mass of the universe remains the samesame..

3. 3. PulsatingPulsating Theory Theory

The universe is supposed to be expanding The universe is supposed to be expanding and and contractingcontracting alternately…in other words alternately…in other words pulsatingpulsating

Right now it’s Right now it’s expandingexpanding.. The expansion is stopped by the pull of The expansion is stopped by the pull of

gravitygravity and begins to and begins to contractcontract again. again. Once it reaches a certain size, an Once it reaches a certain size, an explosionexplosion

would occur and the universe starts to expand would occur and the universe starts to expand again.again.

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Earth’s Spheres Atmosphere: the envelope of gases that surrounds the Earth