EARTH SCIENCE

Earth SystemsEarth Systems

• Ocean Currents and Wind Currents affect weather patterns and landforms.

Earth StructureEarth Structure

• Crust– Rocky outer layer

• Mantle– Thick layer of hot but

solid rock

• Core– Large core of melted

metal

Plate tectonicsPlate tectonics

• Theory of Plate tectonics – Pieces of earth, called plates, move about the

earth.– Check this site out– http://emvc.geol.ucsb.edu/animations/flash/pa

ngea.swf

Continental DriftContinental Drift

• Alfred Wegener (1880-1930)– Hypothesized that continents were once

joined together in a supercontinent– Pangea

• Fossils of the same animals were found on the coasts of South America, Africa, and the Northern tip of Antarctica

Sea Floor SpreadingSea Floor Spreading

• Process which new sea floor is created at mid-oceanic ridges.

• Sea floor spreads apart and magma rises .

• Water cools the magma, creating a new sea floor

Plate BoundariesPlate Boundaries

• Outer earth sits on 12 plates.

• At each plate there is a boundary

• 3 kinds of boundaries– Divergent– Convergent– Transform

Divergent BoundaryDivergent Boundary

• When plates move away from each other.

Convergent BoundaryConvergent Boundary

• Plates come together or collide.

• One plate goes under (subduction) another plate

• Mountain Building

Transform BoundaryTransform Boundary

• Plates slide past each other in opposite directions

• EARTHQUAKES• California San

Andreas Fault

This shows all the boundaries at This shows all the boundaries at the same time.the same time.

• http://www.classzone.com/books/earth_science/terc/content/visualizations/es0804/es0804page01.cfm?chapter_no=visualization

How to tell the age of RocksHow to tell the age of Rocks

• Superposition– Younger rocks are on

top of older rocks– Only if layer of

sedimentary rocks is undisturbed.

Relative dating Relative dating

• Fossils are the age of the rock they are found in.

• Older fossils on the bottom.

• Younger fossils on top.

Plate FoldingPlate Folding

Older layer

Younger layer

Radioactive/Radiometric DatingRadioactive/Radiometric Dating

• The exact age of rock/fossils.

• Scientists can measure the decay of certain elements and determine actual age.

Gravitational forceGravitational force

• The closer the smaller object is to the bigger object, the more gravitational force there is.– As the smaller object moves farther away the less

gravitational force there is.

Gravitational ForceGravitational Force

• As an object gets closer there is a greater gravitational force.

Check out this link to see all the planets revolve around the sun!http://galileo.phys.virginia.edu/classes/109N/more_stuff/flashlets/innerplanets.htm

Click on this link to see the earth going around the sun. Remember when the Earth is closer to the sun there is

more gravitational force!http://www.classzone.com/books/earth_science/terc/content/visualizations/es0408/es0408page01.cfm?chapter_no=04

Stars Basic InfoStars Basic Info

• Give off massive amounts of energy

• Hottest stars appear BLUE

• Next hottest appear RED

• Coolest stars appear Yellow

• You can tell the surface temperature of a star with the naked eye.

Basic Info cont.Basic Info cont.

• Brightest Stars are closest

• Dim stars are farther away.

• No direct way of finding exact mass of stars.

How Stars formHow Stars form

• Star is formed when gas and dust become so hot, fusion starts, and they start to emit energy

• Gravity of this core attracts other particles.

Life Stages of a StarLife Stages of a Star

How Stars Produce EnergyHow Stars Produce Energy

• Nuclear Fusion• Hydrogen nuclei fuse

together to for Helium atoms

Geocentric TheoryGeocentric Theory

• A model of the solar system where stars and planets revolve around Earth.

• Developed by ancient Greeks.

• A.D. 140• NOT HOW THINGS

ARE!!!

Heliocentric ModelHeliocentric Model

• Earth and Planets revolve around sun.

Big Bang TheoryBig Bang Theory

• Theory about how universe came into being from a single moment.

• After the Bang the universe expanded quickly and then cooled.

• Earth is 13-14 Billion Years old• Evidence

– Mathematicians have calculated that stars are getting farther away.

– Cosmic microwave radiation• Energy from initial Big Bang

How We Affect The Earth: How We Affect The Earth: Exponential Population GrowthExponential Population Growth

Implications of OverpopulationImplications of Overpopulation

• Increased CO2 in air

• Decrease O2

– Cutting down trees = less green = less oxygen

• Increased waste• Depletion of natural resources multiplied• Water quality decrease

– Trees and plants prevent erosion– Increased erosion means more soil pesticides running

off into water

WeatherIs the actual condition of the atmosphere in a place at a particular time.

Including: heat, cold, dryness, humidity, precipitation and wind.

ClimateIs the average condition of the weather over a long period of time – usually 35 years.

The Weather can change – The Climate does not change

Weather and ClimateWeather and Climate

• Weather – atmospheric conditions over a short period of time (day), studied by meteorologists.

• Climate – atmospheric conditions over a long period of time (months and years), studied by climatologists.

• Of main interest is precipitation and temperature.

Low Latitudes: Between the tropic of Cancer and Tropic of Capricorn, warm hot climates

North or South of the Equator makes a difference on the temperature and the wind patterns

High Latitudes: Warm when the poles are tilted towards the sun and Cool when the poles are tilted away from the sun

As we move from December to June the number of daylight hours increases due to the tilt of the axis (earth surface receives more direct sunlight). June to December daylight hours get shorter earth cools.

Summer – Energy more intense

Winter – Energy less intense

How does latitude affect climate?

As latitude ________, the averageannual temperature _________.

0° Latitude 90°

Tem

per

atu

redecreases

increases

How does closeness to a large body of water affect climate?

Water __________ the temperature._______ summers. _______ winters.

City B is closer to a large body of water.

Its temperature line is flatter (moderated).

moderates

Cities A & B are located at the same latitude.

Cooler Warmer

How does the Orographic Effect

affect climate?

Windward Side: ___________Leeward Side: _____________

cool, moistwarm, dry

How does elevation affect climate?

As elevation _________, the averageannual temperature __________.

Elevation

Tem

per

atu

reincreases

decreases