430 likes | 569 Views
EARTH SCIENCE. Earth Systems. Ocean Currents and Wind Currents affect weather patterns and landforms. Earth Structure. Crust Rocky outer layer Mantle Thick layer of hot but solid rock Core Large core of melted metal. Plate tectonics. Theory of Plate tectonics
E N D
Earth Systems • Ocean Currents and Wind Currents affect weather patterns and landforms.
Earth Structure • Crust • Rocky outer layer • Mantle • Thick layer of hot but solid rock • Core • Large core of melted metal
Plate 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/pangea.swf
Continental 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 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 Boundaries • Outer earth sits on 12 plates. • At each plate there is a boundary • 3 kinds of boundaries • Divergent • Convergent • Transform
Divergent Boundary • When plates move away from each other.
Convergent Boundary • Plates come together or collide. • One plate goes under (subduction) another plate • Mountain Building
Transform Boundary • Plates slide past each other in opposite directions • EARTHQUAKES • California San Andreas Fault
This shows all the boundaries at 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 Rocks • Superposition • Younger rocks are on top of older rocks • Only if layer of sedimentary rocks is undisturbed.
Relative dating • Fossils are the age of the rock they are found in. • Older fossils on the bottom. • Younger fossils on top.
Plate Folding Older layer Younger layer
Radioactive/Radiometric Dating • The exact age of rock/fossils. • Scientists can measure the decay of certain elements and determine actual age.
Gravitational 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 Force • As an object gets closer there is a greater gravitational force. 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 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
Stars 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. • Brightest Stars are closest • Dim stars are farther away. • No direct way of finding exact mass of stars.
How 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.
How Stars Produce Energy • Nuclear Fusion • Hydrogen nuclei fuse together to for Helium atoms
Geocentric 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 Model • Earth and Planets revolve around sun.
Big 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
Implications 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
Weather Is the actual condition of the atmosphere in a place at a particular time. Including: heat, cold, dryness, humidity, precipitation and wind. Climate Is the average condition of the weather over a long period of time – usually 35 years. The Weather can change – The Climate does not change
The Factors that Affect Climate
Weather 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.
Latitude 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 Low Latitudes: Between the tropic of Cancer and Tropic of Capricorn, warm hot climates
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 average annual temperature _________. increases decreases Temperature 0° Latitude 90°
How does closeness to a large body of water affect climate? Water __________ the temperature. _______ summers. _______ winters. moderates Cooler Warmer Cities A & B are located at the same latitude. City B is closer to a large body of water. Its temperature line is flatter (moderated).
How does the Orographic Effect affect climate? Windward Side: ___________ Leeward Side: _____________ cool, moist warm, dry
How does elevation affect climate? As elevation _________, the average annual temperature __________. increases decreases Temperature Elevation