Unit 1: Water Systems on Earth Chapter 2
Create a mind map with the driving question, Why are Oceans Important?
Remember: Why are oceans so important?
Why are oceans so important? Primary water source for the water cycle
Why are oceans so important? Primary water source for the water cycle Major influence on weather and climate
Why are oceans so important? Primary water source for the water cycle Major influence on weather and climate Support diverse life
Why are oceans so important? Primary water source for the water cycle Major influence on weather and climate Support diverse life Provides humans with food, minerals, and other resources
5 Major Oceans What are the 5 major oceans in the world?
5 Major Oceans Pacific Atlantic Indian Southern Arctic
How were oceans formed?
1Tectonic Plates 2Volcanic Action 3Erosion 4Glaciation How were oceans formed?
Tectonic Plates Tectonic plates: slow moving sections of rock that float over a layer of magma The surface of the earth is made up of tectonic plates Tectonic plates separating formed the oceans we know today
Tectonic Plates At ocean ridges- plates are separating At ocean trenches- plates are colliding
Volcanic Action Water trapped in volcanic materials was released as vapour, cooled, condensed and fell back to the earth This water collected in the lowest parts of the Earth s surfacethe ocean basins Volcanic activity continues to occur at ocean ridges, spreading tectonic plates apart and adding new material to the sea floor
Erosion Erosion: type of weathering in which surface soil and rock are worn away through the action of glaciers, water, and wind Has aided the development of continental drainage systems as material is removed and deposited into ocean basins
Glaciation Glaciers move materials towards the ocean and cause erosion
What does the seafloor look like?
Components of The Ocean Floor Continental Margin Ocean basins begin many kilometres out to sea The area between the basin and the coastline is called the continental margin
Components of The Ocean Floor Continental Margin Ocean basins begin many kilometres out to sea The area between the basin and the coastline is called the continental margin This is made up of the Continental shelf Continental slope
Components of The Ocean Floor Continental shelf the submerged part of the continent between the shoreline and slope
Components of The Ocean Floor Continental slope The slope between the continental shelf and the deep ocean floor
Components of The Ocean Floor Abyssal Plains Wide, open plains (flat areas) on the deep sea floor Formed of thick deposits of sediments
Components of The Ocean Floor Mid-Ocean Ridge Long, undersea mountain chains formed from volcanic eruptions They are a result of magma that has oozed up between plates and then hardened
Ocean topography off the coast of Newfoundland
Ocean Currents Ocean current: A continuous, directional movement of ocean water
Ocean Currents 2 Types of Ocean Currents 1 Surface currents Flow in the top 100-200 m 2 Deep currents Flow below 200 m
Surface Currents Factors that influence surface currents are: 1Wind 2Earth rotation 3Shape of the Earth s continents
Deep Water Currents Factors that influence deep currents are: 1Differences in Water temperature Cold water is more dense- sinks 2 Differences in Salinity Water with a higher salinity is more dense sinks ocean currents video
Ocean Currents Local Ocean Currents 1 Labrador Current (cold water) 2 Gulf Stream (warm water) Refer to map p 54
Ocean Currents Local Ocean Currents 1 Labrador Current (cold water) 2 Gulf Stream (warm water) Refer to map p 54 When the cold air above the Labrador Current meets the warm air above the Gulf Stream, the warm air, cools condenses and forms fog
Ocean Waves Waves: a disturbance on the surface of the ocean that transmits energy Waves are typically caused by wind
2 Main Types of Waves: Ocean Waves 1 Swells Smooth waves caused by wind and storms far out in the ocean 2 Breakers the tumble of water when a wave collapses onshore
*Tsunamis Ocean Waves giant waves caused by earthquakes, landslides or volcanic eruptions Can be very destructive
Tides Tides are The slow rise and fall of the ocean The upper and lower edges of a beach are determined by the high and low tide marks
Tides Tides are caused by the gravitational pull of the moon and the spinning of the Earth The moon exerts a greater force of pull than the sun due to its closer proximity to Earth
Tides Tidal Range: The difference in level between a high and a low tide
2 Types of Tides: 1Spring Tide: Tides Occur when the Earth, Sun and Moon are in a line Causes extra high and low tides 2 Neap Tides: Occur when the Sun and the Moon are at right angles to one another Causes the smallest tidal movements There is little difference between low and high tides
2 Types of Tides: Tides
Shaping our Shorelines Waves have the power to erode and deposit sediments on the shore Tides work with waves to determine the range of shoreline that can be affected by wave action Factors that affect the interaction of waves and tides on the shorelines are: 1 Slope of the shoreline 2Shape of the shoreline 3 Type of rock material 4Wave energy
Shaping our Shorelines Wave energy is concentrated on headlands and spreads out as it reaches bays
Shaping our Shorelines Coastal erosion can lead to many shoreline features Headlands Sea caves Sea Arches Sea Stacks
Shaping our Shorelines
Think-Pair-Share write down two-three points get together with a partner and discuss share with the class How can coastal communities minimize the damage to shoreline property due to waves and tides?
Shaping our Shorelines Wave energy is concentrated on headlands and spreads out as it reaches bays