Unit 4 Flashcards
How do ocean current affect us?
Shipping and Transport- Search and Rescue- Clean Up STSRC
Earth rotates _____ this is why the sun rises in the ____ and sets in the _____.
Counter-Clockwise- East-West
Explain everything about Surface Currents
10%/Gyres/Ekman Spiral/Wind-driven movement o the ocean water at or near the ocean’s surface. 10GEW
Explain everything about Thermohaline (Deep-Ocean) Currents.
90%/ Changes in Density
North Pacific and North Atlantic Gyres rotate _____ and bring warm water from the equator to the _____ side of the continents.
Clockwise-Eastern NClock
Cold water from the poles move along the _____ side of the continents.
Western
South Pacific and South Atlantic gyres rotate ____ and bring warm water to the _____ side of the continents.
Counter-Clockwise- Eastern
Define Thermohaline Currents and identify their causation.
Slow, deep currents that affect the bulk of seawater below the surface; caused by changes in the density of water (changes in temperature and salinity).
Brings _____ water to the poles and _____ waters to the equator.
Warm-Cool
Changes in temperature or salinity could affect _____ & ______.
Agriculture-Fishing AF
Changes in temperature could cause increase in _____.
Hurricanes
_____ of deep, cold, nutrient rich water causes _____ to grow.
Upwelling-Plankton
What are the basic characteristics of a wave?
Crest-Wavelength-Trough-Wave Height-Period CWTWP
Define Crest
Part of the wave highest above undisturbed sea surface.
Define Wavelength
Distance between two crests or troughs.
Define Trough
Part of the wave that is depressed in the lowest below the sea surface.
Define Period
Time required for two successive troughs/crests to pass a point.
What are the two forces that generate waves?
Air-Crust AC
How does the wind generate waves?
As the wind blows on the surface, the crest of the wave reaches a certain known depth into the water, equal to 1/2 of the wavelength. The motion of the water particles decreases as depth increases, until the depth of influence is reached.
An object on a wave does not move forward with the wave energy, but _____ to the same general area.
Returned
At the surface, the orbital motion of an object is equal to the _____.
Height
At a depth of _____ of the wavelength, orbital motion is almost zero.
1/2
What are the types of breaking waves?
Plunging-Spilling-Surging PSS
Define Plunging Breakers and give an example.
Deep to shallow; newport beach. DSN
Define Spilling Breakers and give an example.
Gradual Slope, flat surface; Huntington GFH
Define Surging Breakers
Waves slow down as they come into shallow water.
High energy waves with long wavelengths generally create a beach that is made of _____ size and _____. These beaches are usually made of rocks and boulders.
Uniformly-Larger
Low energy waves with shorter wavelengths create a beach that is made of _____ and _____ grain sizes. These beaches are usually made of mud, silt, or sand.
Mixed-Smaller
List some things about Tsunamis
Speeds of hundreds of miles per hour
Caused by underwater earthquakes, volcanic eruptions, or underwater landslides. EVL
Once the wave reaches shore, it slows, wavelength decreases, energy of wave is being condensed and wave heights increase.
Define Rogue Waves and when do they happen?
Defined as a wave whose height is more than twice the significant wave height.
Likely occurs when two waves with similar lengths and heights come together from opposite directions and create constructive interference of the wave.
Why should we care about tides?
Navigation-Electricity-Weather-Fishing NEWF
Define Tides
Periodic rise and fall of surface water caused by the gravitational force of the moon and the sun and by the rotation of the earth.
Why are the changes in height and time predictable?
Because the movements of the solar system that influence tides are predictable.
Define High Tide.
When tidal crest arrives at a particular location on shore, raising the local sea level. (2 daily)
Define Low Tide
When the trough arrives, lowering the sea level. (2 daily)
Define Flood Tide
A rise or incoming tide between low and high tide. FR
Define Ebb Tide
A falling or outgoing tide between high tide and low tide. EF
Define Tidal Range
The vertical distance between high tide and low tide is the tidal range. (Largest in the world: Bay of Fundy Canada)
Newton’s Law of attraction states that the gravitational attraction between two bodies is _____ proportional to their masse, and _____ proportional to the square of the distance between the bodies.
Directly-Inversely
Define Spring Tides.
Earth, moon, and sun are lined up (full/new moon).
Define Neap Tides.
Earth, moon, and sun are 90 degrees with respect to one another.
The sun has _____ of the tide-generating force of the Moon.
46%
There are ______ spring tides and _____ neap tides in a tidal month.
2-2
Tides are _____.
Predictable.
