Transcript high tide
Focus Question (and Answer!)… What causes the seasons? The tilt of the Earth on its axis as it revolves around (orbits) the Sun. Earth’s Orbit and Seasons… 1. The ecliptic is… …the plane on which Earth orbits around the Sun http://en.wikipedia.org/wiki/Ecliptic Earth’s Orbit and Seasons… 2. The tilt of Earth’s axis relative to the ecliptic is 23.5 degrees. http://republicanredefined.com/2010/03/02/chile-quake-shifted-earths-axis-and-made-days-shorter/ The Tilt of All the Planets! http://climatechangepsychology.blogspot.com/2011/07/chris-colose-milankovitch-cycles.html http://www.exploratorium.edu/ancientobs/chaco/HTML/TG-shadows.html 3. Draw The Seasons! P. 760 Earth’s Orbit and the Seasons! 4a. What causes summer in the northern and southern hemispheres? when it is tilted toward the Sun during Earth’s orbit 4b. What causes winter in the northern and southern hemispheres? when it is tilted away from the Sun during Earth’s orbit Earth’s Orbit and Seasons… 5 . The seasons in the northern and southern hemispheres are opposite each other because… When 1 hemisphere is tilted towards the Sun, the other is tilted away from it http://www.onlytoptens.com/wp-content/uploads/2011/08/top-10-documentaries-march-of-the-penguins.jpg Seasons - Perihelion 6. Earth is closest to the Sun in January a. Our winter! b. This is called perihelion http://solarsystem.nasa.gov/scitech/display.cfm?ST_ID=2517 Seasons - Aphelion 7. And farthest from the Sun in July a. our summer! b. This is called aphelion But in Antarctic it is winter (which makes it tough on the penguins!) Lesson 5 Changes in The Seasons – Precession and Nutation Think About It… What would happen to the average temperatures during our winter if Earth was tilted MORE on its axis ? Focus Question… What circumstances can bring about a long term change in the seasons? Precession Precession is… the wobble in Earth’s rotational axis. 1. One full cycle of precession takes… 26,000 years! 2. The force that causes precession is… the sideways pull of the Moon & Sun on the Earth’s bulging equator. The Moon’s orbit is tilted 5° which over time pulls on Earth… http://earthsky.org/astronomy-essentials/what-is-the-ecliptic Precession… 3. Our current north star is… Polaris In about 12,000 years, our new north star will be… Vega http://www.wwu.edu/skywise/a101_precession.html Precession and Our Seasons… 4. Draw this! Aphelion Perihelion Winter Summer July In 14,000 yrs January Aphelion Perihelion Summer Winter July Present January http://earth.usc.edu/classes/geol150/stott/variability/orbitalchanges.html A New North Star and Our Seasons… 5a. Winters in the N. hemisphere will be… in June, July, and August It will be colder here because Earth will be farthest from the Sun. 5b. Summers in the N. hemisphere will be… in December, January, and February It will be warmer here because Earth will be closest to the Sun. Precession Clips… http://www.youtube.com/watch?v=0qHjtp4cdCA 3 minute clip: demonstration of precession http://www.youtube.com/watch?v=Dw4Xhw4q4ec Very short model of precession http://www.cgrer.uiowa.edu/people/carmichael/atmos_course/ATMOS_PROJ_99/bilskemp/natural_variability.html Nutation… Nutation is… … a change in the angle of tilt of Earth’s axis 1. Present tilt of Earth’s axis is 23.5°. 2. The tilt can vary from 22.1° to 24.5 °. http://www.cgrer.uiowa.edu/people/carmichael/atmos_course/ATMOS_PROJ_99/bilskemp/natural_variability.html Nutation… 3a. If the angle of tilt decreased to 22.1… there would be less of a temperature difference b/tw seasons. 3b. If the angle of the tilt of Earth’s axis increased to 24.5… there would be more of a temperature difference b/tw seasons. 4. Draw Nutation p. 373 Bellringer On a sheet of paper, answer the questions that are hanging around the room. You do not need to do them in order. Turn the answers into the basket up front Lesson 6 Tides Perigee/apogee Perigee: the point in the orbit of the moon or a satellite at which it is nearest to the earth. Apogee: the point in the orbit of a moon or satellite at which it is farthest from the earth. Think About It… Tides Lesson How would Earth’s oceans be affected if Earth did not have a moon? Focus Question… What forces and heavenly bodies cause the tides? Tides… Tides are caused by… the gravitational attraction among Earth, the Moon and the Sun. 1. Tides are… the periodic rise and fall of sea level. a. High tide… highest level to which the water rises b. Low tide… lowest level of the water http://www.amusingplanet.com/2012/03/tides-at-bay-of-fundy.html Tides: Bay of Fundy… Low Tide High Tide http://www.srh.noaa.gov/jetstream/ocean/fundy_max.htm http://www.listentothewind.com/fundy-bay-drive-and-sights/ Bay of Fundy National Park, New Brunswick, Canada High Tide Same Rocks… Low Tide Tide Coming In… A bit more… Notice the water level on the rocks… Tide’s In! 2. What forces & heavenly bodies cause the tides? GRAVITY! gravitational pull of Moon on oceans facing it causes high tide Another bulge occurs on the opposite side, since the Earth is also being pulled toward the moon (and away from the water on the far side). The Cause of Tides… Why are there tides on both sides? As gravitational force acts to draw the water closer to the moon, inertia attempts to keep the water in place. But the gravitational force exceeds it and the water is pulled toward the moon, causing a “bulge” of water on the near side toward the moon (Ross, D.A., 1995). On the opposite side of the Earth, or the “far side,” the gravitational attraction of the moon is less because it is farther away. Here, inertia exceeds the gravitational force, and the water tries to keep going in a straight line, moving away from the Earth, also forming a bulge (Ross, D.A., 1995). What else? the sun’s tide-generating force is about half that of the moon Because the earth rotates on its axis the moon completes one orbit in our sky every 25 hours (Not to be confused with moon's 27 day orbit around the earth), we get two tidal peaks as well as two tidal troughs. These events are separated by about 12 hours. Since the moon moves around the Earth, it is not always in the same place at the same time each day. So, each day, the times for high and low tides change by 50 minutes. The Cause of Tides… 3. What motion causes tides at location to change every 6 hours? Earth’s rotation on it’s axis every 24 hours and… Moons rotation every 24 hours and 50 minutes and… 4. The times of tides vary each day because the moon orbits the Earth every 28 days Earth rotates through two tidal bulges every lunar day o There are two high tides and two low tides every 24 hours 50 o High tides occur 12 hours and 25 minutes apart. o It takes six hours and 12.5 minutes for the water at the shore to go from high to low, or from low to high. http://loneswimmer.com/2010/08/23/tides-for-swimmers-part-1-theory/#jp-carousel-535 Spring Tide… Twice a month, the Earth, Moon, & Sun align (line up) causes the Moon & Sun to pull together on Earth’s oceans. Higher high tides / lower low tides Twice a month, the Earth, Moon, & Sun will form a right angle which causes the Moon & Sun to pull from different directions on Earth’s oceans. Evens the tides Neap Tide… http://www.yourdictionary.com/neap-tide http://csep10.phys.utk.edu/astr161/lect/time/tides.html Compare the Spring Tides & Neap Tides Lunar Eclipse Lunar eclipses occur when Earth's shadow blocks the sun’s light, which otherwise reflects off the moon. When is our next one? The next lunar eclipse is September 27 It is a total lunar eclipse while the moon is at perigee The next one will be in 2033 Lesson 7 Energy Reactions Think About It… Is it possible to make electricity by using the same process that powers the Sun? Focus Question… What process powers the Sun and what forms of Energy does that process produce? What is the difference between fusion, fission, & combustion? Great Sun Pic from NASA… Fun Sun Facts by NASA… https://solarsystem.nasa.gov/planets/profile.cfm?Object=Sun BTW… Our Sun is basically a stable hydrogen bomb – or a giant fusion reactor! Fusion… a. Fusion occurs in the stars! (our Sun) bi. During fusion, the two atoms that fuse to form a helium atom are the H isotopes deuterium & tritium Fusion 1. Fusion is… – the fusing of smaller, lighter hydrogen atoms to form a larger, heavier helium atom (which releases energy) Can we do fusion? NO! For fusion to occur on Earth, you need a temperature of at least 100 million degrees Celsius— six times hotter than the core of the sun. We would need to put in more energy than we would get out of a fusion reactor! Fission 2. Fission is… – splitting of bigger, heavy atoms (like uranium or plutonium) into smaller, lighter atoms 2b.Fission 2b. Fission is used on Earth … – in nuclear power plants & submarines (to generate electricity) www.pollutionissues.com Fusion and Fission: Nuclear Reactions 2c. Fusion and fission are both nuclear reactions because… …the nuclei of atoms are fusing (in fusion) OR splitting (in fission). (Remember… That’s the center part of the atom where protons and neutrons are located) New atoms are made in both types of reactions. Bellringer:Compare and Contrast You have 8 minutes Fission vs. Fusion Create a diagram like on the board for your notes-keep it in your notebook. Precession vs Nutation Create a Venn diagram comparing and Precession and nutation –keep it in your notes Review: Fission vs Fusion Fission Fusion •Nuclear reaction •Nuclear reaction •Splits larger atoms into smaller atoms •Fuses smaller atoms into larger atoms •We can do it here on Earth for energy •We have been unable to use fusion for energy •Happens in Nuclear power plants and submarines, for example •Happens in stars and our sun (which is a star), for example Review: Precession & Nutation Precession Nutation • Change in direction of Earth’s axis • Change in angle of tilt of Earth’s axis from 22.1 to 24.5 • Takes 26,000 years • • Earth axis move in the shape of a circle Takes 41,000 years to move from 22.1 to 24.5 degrees • Caused by the moon, sun, and other planets • Our north star “changes” • • Caused by the pull of the moon and sun Has an effect on seasons/climate http://en.wikipedia.org/wiki/Combustion Combustion 3. Combustion is… burning of a fuel in presence of O2 (oxygen) to produce energy (heat & light) a. It is a chemical reaction which recombines atoms. (FUEL) Methane Combustion used in… Vehicles Fireplaces Power Plants (Belews Creek) http://www.news-record.com/news/article_73ce9953-637d-5c7c-bfdd-49fee0a35773.html http://en.wikipedia.org/wiki/Volkswagen_New_Beetle Radiation from the sun One of the Effects of Ultraviolet Radiation! Focus Question… How are the harmful forms of radiation from the Sun deflected away or filtered so that they don’t reach living things? The Sun’s Energy… 1. Electromagnetic radiation consists of … … electric & magnetic disturbances that travel through space as waves. 2. The electromagnetic spectrum… …organizes forms of EM energy by wavelength 3. The Sun produces electromagnetic radiation across the spectrum… radio waves, microwaves, infrared energy (heat), visible light, ultraviolet radiation, xrays, & gamma rays The Electromagnetic Spectrum… 4. The shorter the wavelength, the more harmful the energy! http://www.lbl.gov/MicroWorlds/ALSTool/EMSpec/EMSpec2.html The Ozone Layer… 5. Which gas blocks ultraviolet radiation from the Sun? Ozone (O3) a. It is found in the stratosphere. b. Chlorofluorocarbons (CFCs) damage O3. c. These are found in aerosols, coolants, & cleaners. http://mmedia.pl/ozone-layer-diagram-for-kids Solar Wind and Earth’s Magnetic Field 1. Solar wind is… …a supersonic plasma (Remember, that’s charged particles or ions) that flows outward from Sun at high speeds &… …bathes planets in a flood of highenergy particles. (Which isn’t very good for us!) Solar Wind What protects us from the deadly solar wind? http://www.cnn.com/2013/06/27/world/europe/star-trek-shield http://www.youtube.com/watch?v=zoK-tPS_bYE http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=10984 Solar Wind and Earth’s Magnetic Field… 2. Earth’s magnetic field protects us from the solar wind by… deflecting these particles and trapping them in two huge rings (Van Allen belts) http://www.redorbit.com/education/reference_library/space_1/solar_system/2574610/van_allen_radiation_belt/ Earth’s Magnetic Field… 3. Draw and label this! The Strength of Earth’s Magnetic Field… Our magnetic field is decreasing by 5% a century Jupiter has a super-strong magnetic field What would happen if our magnetic field was much stronger? Take a look… https://www.youtube.com/watch?v=etPXBm 0zRvM Solar Wind and Earth’s Magnetic Field… 4. The auroras are created when… … high-energy particles in Van Allen belts collide with gases in Earth’s atmosphere & give off light See next slide… The Auroras… http://www.lovethesepics.com/2011/02/24-amazing-auroras-aurora-borealis-aurora-australis/ Lesson 9 Energy For Earth… Think About It… What would happen to Earth if the Sun were turned off today? Focus Question… How does the Sun’s energy warm Earth’s surface and atmosphere? Energy For Earth… 1. Radiation is … transfer of energy through space by EM waves (visible light, ultraviolet radiation, & other) http://virtualskies.arc.nasa.gov/weather/images/2b1.png Energy For Earth… 1a. The Sun’s energy reaches Earth by the process of radiation. 1b. About 50 % of the Sun’s energy is absorbed by Earth’s surface. 1c. Remember – ozone blocks most of the UV radiation. http://ossfoundation.us/projects/environment/global-warming/earths-radiation-budget Differential Heating… 1d. Which heats up and cools down more slowly – water or land? This is called differential heating. This is what moderates the climate in coastal areas. In winter, the ocean acts like a giant heater and in summer, the ocean acts like a giant air conditioner. Differential Heating and North Carolina… Our moderate coast – The Outer Banks! 2. Conduction is… the transfer of energy that occurs when molecules collide a. Air molecules just above Earth’s surface are warmed by conduction. b. Energy moves from your hand to your desk. Why? Energy for Earth… Heat waves over hot sand! http://visualparadox.com/wallpapers/dryseason1600.htm Energy for Earth… 3. Convection is… the transfer of energy by the flow of a heated substance a. Warm air will rise. b. When the warm air gets high enough, it cools and sinks. c. This creates a convection current. http://avstop.com/ac/fig5-9.jpg Energy for Photosynthesis… 1. During photosynthesis, solar energy is transformed into chemical energy (food). 2. This occurs in plants, algae & some bacteria. 3. For this to occur, there must be water, CO2, 4. Energy source: sunlight. 5. In plants, this occurs in chloroplasts. http://abhsscience.wikispaces.com/Photosynthesis+TD 6. Draw Photosynthesis…