11.2 Flashcards
Ocean current?
A large amount of ocean water that means, in a particular or unchanged direction
How many ocean currents are there in the world?
Over 20
What do ocean currents Carry?
Vast quantity of dissolved minerals, Solar energy, carbon dioxide, plankton
Plankton?
Microscopic plants and animals that are essential food sources for all the other organisms in the ocean
What is the largest ocean current in the world?
Antarctic circumpolar
What r the two types of ocean currents?
Surface currents
Deep water currents
Wind action?
The movement of surface currents
What is the movement of deep currents caused by?
Temperature and salinity of water
What’s another way that the ocean moves?
Waves ruffling the surface of the water and the rise and fall of the water level (tide)
What makes surface currents move?
Wind, spinning of earth on its axis, the shape of earths land masses, uneven heating of the atmosphere
Wind is the result of…
Masses of air moving rapidly from one area to another cuz of temperature differences
How is wind created
As air get heated by the sun, the Particles gain energy and expand. This makes them less dense so they rise. When that happens, cooler, denser air quickly moves into the area left empty by the rising air molecules
What are the direction and speed of surface currents connected to?
Connected to the direction and speed of the wind blowing over the water
What does the spinning of earth on its axis effect?
Winds and ocean currents
What way does earth spin?
West to east (clockwise)
How does the earth spinning effect ocean currents and winds?
as winds and currents move over this spinning body, there path gets redirects (deflected) depending in which side of the equater there on
What is this alteration of direction called?
The Coriolis effect
What direction would the wind be blowing if u were standing on the surface if the earth in the northern hemisphere?
Right (east)
What direction would the wind be blowing if you were at standing on the surface of the earth in the Southern Hemisphere?
Left (west)
How do continents affect surface currents?
Effect how and where surface currents move
Even though all the oceans are connected, how do we treat it?
We treat it as 5 different ocean basins separated by the natural barriers of the continents
What makes deep currents move?
Water temperature and salinity
What does temperature affect?
The density of water
The colder the water, the greater or lesser the density?
Greater
Where does denser, colder water, tend to sink?what will the water do?
Sink beneath warmer water, where the water will move along the ocean floor.
What is the sinking and movement of dense water beneath surface water called?
Density current
What are the three layers of ocean water?
Surface layer (mixed layer), thermocline, deep water
What’s the warmest layer of the oceans and why?
The surface water where the Suns energy heats the water
What keeps the temperature mostly consistent in surface water?
Surface currents
What is layer in the ocean where the temperature drops rapidly ?
Lower down where the effects of the sun cannot be felt (thermocline)
Approximately, what is the temperature in the deep water?
Approximately 2°c
Where do thermocline a also occur?
Lakes
Is water with high salinity or low salinity denser?
High
How does the salinity in ocean water change from one place to another?
- adding fresh water to ocean water decreases density
- Ice melting
How do u increase the salinity?
- evaporation takes water out of a system leaving the water saltier
- freezing - salt in the water is left behind when the fresh water freezes
What is the freezing point for salt water?
1.9°c
Where is the saltiest, coldest, and densest water found?
North and South Pole
Upwelling?
The rising of the water from the deep
What does upwelling bring to the surface and what does this feed?
Brings nutrient rich water to the surface which feeds plankton
How can surface winds coming off land cause upwelling?
As strong winds blow the surface water away from the shire, deep ocean water rises to take its place
Why does bc water have a greenish tint?
Because of the great abundance of organic material found here
Why is bc waters the perfect place for tiny ocean plants called phytoplankton?
Upwelling provides the right amount of balance of temperature and nutrients supply making the perfect environment for phytoplankton
Swells?
Lately, rolling waves that form In The open oceans
Breakers?
When swells meet shallow waters
How are tsunamis caused?
- earthquake beneath the ocean floor
- a landslide
- volcanic eruption
What do waves have the power to do?
Power to erode even the hardest rocky coast and deposited great amount of sediments in shore
What does the quickness of a coastline eroding depend on?
- force if wave hitting the land
- type of rock the land is made from
What type of coastlines are created as a result of erosion and deposition?
- steep cliffs that rise like rock walls from the water
- sandy beaches with long, low slopes
Headlands?
Sections of the coastline that extend into the ocean
Much of how waves behave once they reach a coastline depends on…
Depends on the shape of the coastline
Why do headlands happen?
Typically they are made of harder rock than the surrounding land
Bays?
Indented areas in the coastline where the ocean reaches into the land
What happens when waves reach a bay?
Waves arnt traveling with the same amount of energy as they did when they hit the headlands
Tide?
The daily cycle of rising and falling ocean water
Who are tides caused?
Gravitational attraction between the earth and the moon
Why do earth and moon have a gravitational attraction?
Because they are so close to eachother
What side is the gravitational attraction the strongest?
The side where the earth is closest to the moon
What way does the water go?
Where the gravitational attraction is the strongest, meaning that the water is getting pulled away from the earth
What is the result of the gravitational attraction?
Bulge, or rise, In the water creating a high tide
What is happening on the side of earth opposite of the moon?
The water is now farther to the moon than the earths mass is. Therefore, earth is being pulled by the moon away from the water, which causes a bulge on this side of the water too
What is happening to the water in between both high tides?
Water is being pulled towards the bulges, causing low tides in those areas
At any given point on earth, how many high and low tides are experienced each day?
2 high tides
2 low tides
Tidal range?
The difference between high and low tides
What has a big effect on tides range?
The shape of coastlines
Why does the bay of fundi have a high tides range?
The bay of fundi is long and narrow. So water rushes towards the shire at high tide, it gets funnelled into a smaller area
How does the sun play a big role on tides?
When the sun and moon are lined up, there gravitational pull is combined to creat especially high or low tides
What are these tides called when the sun and moon are lined up and how many times do they occur each month?
Spring tides and they occur twice a month
What happens when the sun and moon arnt aligned
There gravitational pull on earths water is reduced (high tides arnt as high and low tides arnt as low as usual)
What is it called when the sun and moon are not aligned?
Neap tides
