Ocean Currents Chapter 16.1
Ocean Currents Masses of ocean water that flow from one place to another.
Currents Two types of ocean currents: Surface currents Deep currents
Surface Currents Currents that ONLY move horizontally in the UPPER part of the Oceans surface Develop from friction between the ocean and the wind that blows across the surface.
Color your surface current map using the Key on your Surface Current Map! BLUE = Cold Current RED = Warm Current
Global Winds Create Currents Draw and Label a Global Winds Diagram according to this diagram.
Gyres Huge circular-moving current systems that are driven by the global winds. 5 main gyres!
Gyre Plastic Pollution
What if this was YOUR home?
Locate the 5 main Gyres on your surface current map Locate the 5 main Gyres on your surface current map. Label the Gyres on your map
The Coriolis Effect Video Explanation The deflection of the currents from their original course because of the Earth’s rotation. Just like a merry go round!
Because the Earth Spins Currents are deflected: To the Right in the Northern Hemisphere To the Left in the Southern Hemisphere
Why? Great Britain and Alaska are at similar latitudes, yet Great Britain is about 25 degrees warmer than Alaska…
Ocean Currents and Climate Gulf Stream is a great example of bringing warmth to a high latitude. It brings heat from the equator region to areas more North and South
Deep Currents VERTICAL (up and down) currents of ocean water Caused by differences in water density Dense water SINKS LESS dense water RISES
Color in your Global Conveyor Belt diagram Deep Currents A result of temperature or salinity changes temp = sinks salinity = density sinks Color in your Global Conveyor Belt diagram
Color in your Global Conveyer Belt Map Cold = Blue Warm = Red
Tides Chapter 16.2
What is a Tide? The rise and fall of the sea level.
The gravitational pull of the Moon and the Sun make the tides
Sun Vs. Moon The Sun is much larger than the Moon but has ONLY about ½ of the power of the Moon on tides WHY? Because the Moon is Closer
Types of Tides Two types of tides: Spring Tides Neap Tides
Spring Tides The Sun, Moon and Earth are in a straight line.
Spring Tides Come once every two weeks. During a full and new moon phase
Spring Tides Highest High Tides and Lowest Low Tides Why?
Spring Tide ALL Gravitational Force!!
Neap Tides When the Sun Moon and Earth are at right angles.
Neap Tides Happens about twice a month Happens at the 1st and 3rd quarter Moon Phase
Neap Tides Tidal Range is the smallest. (NOT MUCH DIFFERENCE between high tide and low tide!) Why?
Neap Tide Forces TWO different forces Gravitational and Centrifugal
Spring Tide vs. Neap Tide In the boxes at the bottom of your notes Spring Tide vs. Neap Tide Neap Tide Force is from two directions at the same time Spring Tide Force is all in one direction HIGHEST HIGHS & LOWEST LOWS LOW HIGHS & HIGH LOWS
Tide Animations https://www.youtube.com/watch?v=5ohDG7RqQ9I How Tides Work https://www.youtube.com/watch?v=sMKvqMUZwV4 Time Lapse High Tide https://www.youtube.com/watch?v=OP0cpXpw8yk The Bay of Fundy
One Tidal Cycle = 24 hours & 50 minutes There are usually two high tides and two low tides each day.
Why the extra 50 minutes? As the Earth is rotating and revolving the Moon is revolving as well. It takes an extra 50 minutes for the Earth to catch up with the Moon.
Tidal Cycles – 3 types
Diurnal Tidal Cycle One high tide and one low tide per tidal cycle. Uncommon
Semidiurnal Tidal Cycle 2 identical high tides and two identical low tides per tidal cycle
Mixed Semidiurnal Tidal Cycle 2 High and 2 Low tides – all of different heights.