Option B: Oceans and Coastal Margins

Question 1

Ocean Current

Answer 1

A seasonal directed movement of seawater generated by forces acting upon this mean flow, such as breaking waves, wind, the Coriolis Effect, temperature and salinity differences.

Question 2

Tide

Answer 2

Caused by the gravitational pull of the sun and moon.

Question 3

Surface ocean currents caused by the influence of _____ winds blowing steadily across the seas surface.

Answer 3

Prevailing

Question 4

Gyre

Answer 4

A large system of rotating, usually circular ocean currents.

Question 5

How many “main” gyres are there in the world?

Answer 5

Five

Question 6

What direction (clockwise / anti-clockwise) do gyres in the Northern hemisphere flow compared to in the Southern hemisphere?

Answer 6

Clockwise in Northern Hemisphere

Anti-clockwise in Southern Hemisphere

Question 7

What and in what direction does the Gulf stream transport?

Answer 7

Transports heat northwards and then eastwards across the North Atlantic (USA –> UK)

Question 8

In the redistribution of heat, where does warm vs. cold water flow in terms of the equator?

Answer 8

Warm water travels away from the equator to the colder regions.
Colder water travels to the equator to heat up.

Question 9

Why are ocean currents so important? (3 reasons)

Answer 9

1. Bring nutrients to the surface
2. Transfers heat (redistribution)
3. Responsible for mass migration of marine species

Question 10

Upwelling Currents

Answer 10

Bring nutrients for fish, birds and people at the surface from the ocean floor (where most nutritious organic matter is located).

Question 11

Downwelling Currents

Answer 11

Salty and cold but brings oxygen to species at ocean floor. Otherwise the ocean floor would become toxic due to all the biproducts of decomposition.

Question 12

Specific Heat Capacity

Answer 12

The amount of energy it takes to raise the temperature of a body.

Question 13

The global ocean conveyor belt is…..

Answer 13

a constantly moving system of deep-ocean circulation driven by temperature and salinity.

Question 14

Thermohaline Circulation

Answer 14

The idea that global conveyor belt is driven by temperature and salinity changes.

Question 15

Dune

Answer 15

A mound of sand formed by the wind along a beach.

Question 16

Dunes form when….

Answer 16

Wind blows sand into a sheltered area behind an obstacle. Dunes grow as grains of sand accumulates.

Question 17

What is the process called of sand moving up the beach and describe it.

Answer 17

Saltation.

“Hopping” of sand particles up the beach.
(Suspension) = carried by wind
Saltation = rolling / hopping

Question 18

(Dunes) Vegetation is required for ____

Answer 18

A dune to become stable. In fully developed dune systems, the process of succession takes place where the range and density of vegetation changes from youngest to oldest dunes.

Question 19

Name an example of a sand dune vegetation and the adaptations it has had to overcome.

Answer 19

Marram grass / sea couch:

Adapted to salty, dry, windy and nutrient poor conditions,

Question 20

What is needed for dunes to form? (4 things)

Answer 20

1. Wind (for saltation to occur and transport sand upwards).
2. Sand (dunes don’t form with pebbles)(preferably dry sand as wet sand cannot be transported by the wind.
3. Wide beach (saltation needs time and space.
4. Flat surface (dunes can’t form on a slope).