Unit 1: Water Systems on Earth Chapter 2

Transcription

1 Unit 1: Water Systems on Earth Chapter 2

2 Create a mind map with the driving question, Why are Oceans Important?

3 Remember: Why are oceans so important?

4 Why are oceans so important? Primary water source for the water cycle

5 Why are oceans so important? Primary water source for the water cycle Major influence on weather and climate

6 Why are oceans so important? Primary water source for the water cycle Major influence on weather and climate Support diverse life

7 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

8 5 Major Oceans What are the 5 major oceans in the world?

9 5 Major Oceans Pacific Atlantic Indian Southern Arctic

10 How were oceans formed?

11 1Tectonic Plates 2Volcanic Action 3Erosion 4Glaciation How were oceans formed?

12 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

13 Tectonic Plates At ocean ridges- plates are separating At ocean trenches- plates are colliding

14 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

15 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

16 Glaciation Glaciers move materials towards the ocean and cause erosion

17 What does the seafloor look like?

18 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

19 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

20 Components of The Ocean Floor Continental shelf the submerged part of the continent between the shoreline and slope

21 Components of The Ocean Floor Continental slope The slope between the continental shelf and the deep ocean floor

22 Components of The Ocean Floor Abyssal Plains Wide, open plains (flat areas) on the deep sea floor Formed of thick deposits of sediments

23 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

24 Ocean topography off the coast of Newfoundland

25 Ocean Currents Ocean current: A continuous, directional movement of ocean water

26 Ocean Currents 2 Types of Ocean Currents 1 Surface currents Flow in the top m 2 Deep currents Flow below 200 m

27 Surface Currents Factors that influence surface currents are: 1Wind 2Earth rotation 3Shape of the Earth s continents

28 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

29 Ocean Currents Local Ocean Currents 1 Labrador Current (cold water) 2 Gulf Stream (warm water) Refer to map p 54

30 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

31 Ocean Waves Waves: a disturbance on the surface of the ocean that transmits energy Waves are typically caused by wind

32 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

33 *Tsunamis Ocean Waves giant waves caused by earthquakes, landslides or volcanic eruptions Can be very destructive

34 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

35 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

36 Tides Tidal Range: The difference in level between a high and a low tide

37 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

38 2 Types of Tides: Tides

39 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

40 Shaping our Shorelines Wave energy is concentrated on headlands and spreads out as it reaches bays

41 Shaping our Shorelines Coastal erosion can lead to many shoreline features Headlands Sea caves Sea Arches Sea Stacks

42 Shaping our Shorelines

43 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?

44 Shaping our Shorelines Wave energy is concentrated on headlands and spreads out as it reaches bays