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Grade 8 Earth Science. Chapters 14 & 16: Atmosphere & Climate. Composition of Earth’s Atmosphere . Layers of Earth’s Atmosphere. Info. Relating to the Atmosphere. Troposphere- Ionosphere- Where does weather occur? Why does the frequency of radio stations break up?. Ozone Layer.
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Chapters 14 & 16: Atmosphere & Climate
Info. Relating to the Atmosphere • Troposphere- • Ionosphere- Where does weather occur? Why does the frequency of radio stations break up?
Ozone Layer • What is ozone? • What is the ozone layer? • Where is the ozone layer located? • How does ultraviolet radiation affect you? • Describe CFC’s (chlorofluorocarbons)…
Water Cycle Words to Know • What is a cycle? • Evaporation- Transpiration- • Condensation- • Precipitation-
Movement of Air • Winds are caused by the uneven heating between the Equator & the Poles • Hot air rises • Cool air settles • Coriolis Effect: deflects all free-moving objects (such as air and water) to the right north of the equator and left to the south
Wind Systems • The Prevailing Winds are caused by the rotation of the earth and the position of the continents. SURFACE WINDS • Easterlies – • Westerlies - • Trade Winds – • Doldrums -
HIGH ALTITUDE AND LOCAL WINDS • Jet Stream – winds at high altitude (where the jets fly). Flows from west to east in northern hemisphere and opposite direction in the southern hemisphere • Local Winds – are caused by convection currents examples are Sea and Land Breezes
Climate Words to Know: Tropics- Polar Zones- Temperate Zones-
What is the difference between weather & climate?
El Nino ~ La Nina Some climatic changes last longer than a season… El Nino is a climatic event that starts in the tropical Pacific Ocean and sets off changes in the atmosphere (unusually warm ocean temperatures) La Nina is El Nino’s counterpart which causes unusually cold ocean temperatures
Climatic Changes • Greenhouse Gases- • Global Warming (Climate Change)
Chapter 17: Ocean Motion How do oceans affect you? How do you affect oceans?
Composition of Oceans • Earth’s surface is ______% ocean. • _________ is a measure of the amount of solids dissolved in seawater. • It has remained nearly ____________ for years.
Surface Currents • Move water horizontally • Parallel to earths surface • Powered by winds Importance: distribute equatorial heat to other areas of earth
Ocean Waves & Tides • Wave- rhythmic movement that carries energy through ________ or _______ • Ocean Waves carry energy through _________
TIDES • Tide = ______ and ______ in sea level • Tidal Range = the difference between the level of the ocean at ______ _______ and ______ _______ Tides are affected by the gravitational pull of the _______ and _____ on the earth’s waters. The moon is closer to earth, and therefore, exerts a _________ gravitational pull.
The Seafloor Ocean Basin Features • Continental shelf- • Continental slope- • Abyssal plains- Plate Boundary Structures • Mid ocean ridge- • trench
Mining the Ocean Floor Salt has always been collected from the ocean water. Now, we also collect oil, gas & minerals from the sea.
Life in the Ocean Energy Relationships: - photosynthetic organisms capture the sun’s energy and make food using light energy, carbon dioxide, and water through _______________ - chemosynthetic organisms do not rely on sunlight; instead, they rely on ____________
ASTRONOMY!!! Chapter 22: Sun-Earth-Moon System
Planet Earth Data • Sphere: round, 3-D object whose surface at all points is the same distance from its center • Axis: imaginary line around which earth spins • Rotation: spinning of Earth on its axis • causes day & night • 1 rotation takes 24 hours
Earth’s Revolution • Revolution: yearly orbit around the sun • Earth’s orbit is an ellipse (NOT “circle” or “eclipse”) • Revolution around the sun takes 365 days
SEASONS • Earth’s TILT on its axis causes the seasons • Hemisphere tilted toward the sun receives more hours of sunlight & direct rays
Earth’s Moon • The moon rotates on its axis and revolves around the earth once every 27.3 days. • Because these two motions take the same amount of time, we only see ONE side of the moon.
Moon Phases • Moon Phase: apparent change in the shape of the moon as seen from earth • Depends upon the relative positions of the earth, sun and moon • WAXING = more of the moon becomes visible • WANING = less of the moon becomes visible
Solar Eclipse- moon comes between the earth & sun, casts a shadow on earth