Lecture 2 - Background Oceanography

Question 1

Ocean basins (definition)

Answer 1

Bodies of water bounded by the continents; Pacific, Atlantic, Indian, and Arctic

Question 2

What is the average depth of the ocean?

Answer 2

3,800 meters

Question 3

Continental shelf (definition)

Answer 3

Shallow (<200m) extensions of the continents underwater

Question 4

Seamounts (definition)

Answer 4

Underwater mountains, 100s to 1,000s of meters high

Question 5

Mid-ocean ridges (definition)

Answer 5

The spreading centers of tectonic plates

Question 6

Trenches (definition)

Answer 6

Deep locations where an oceanic plate is being subducted under another plate

Question 7

Continental slope (definition)

Answer 7

The relatively steep transition between continent and abyssal plain (200-300m)

Question 8

Abyssal plain

Answer 8

The vast flat expanses of ocean floor (300m-600m)

Question 9

What are the 5 classifications of the oceanic water column from the surface to the deepest ocean?

Answer 9

1) Epipelagic
2) Mesopelagic
3) Bathypelagic
4) Abyssopelagic
5) Hadalpelagic

Question 10

What are the 5 classifications of the seafloor?

Answer 10

1) Continental shelf
2) Continental slope
3) Abyssal plain
4) Trench

Question 11

Land is on average ___ than the ocean is on average deep

Answer 11

Lower

Question 12

True or false. The continental shelf constitutes a large portion of the ocean floor?

Answer 12

False, shelves occupy only a few percents

Question 13

The 1)___ is the largest habitat on our planet, covering about 2)___ of earth’s surface

Answer 13

1) deep sea

2) ~65%

Question 14

Hawaii is surrounded by ___

Answer 14

deep ocean

Question 15

What drives surface currents in the ocean?

Answer 15

Wind

Question 16

What causes differential heating of the atmosphere?

Answer 16

There is more solar energy at the equator than at the poles.

Question 17

What is the result of differential heating of the atmosphere?

Answer 17

Air heats, expands, and rises at the equator. It then radiates energy, cools, and sinks at the poles.

Question 18

Hadley cell (definition)

Answer 18

Warm air cools before getting to the poles and sinks at ~30 degrees latitude

Question 19

Polar cell (definition)

Answer 19

Cool air warms as it moves across earth and rises at ~60 degrees latitude

Question 20

Ferrel cell (definition)

Answer 20

Warm air rises at ~60 degrees, but cools as it moves southward towards the equator and descends at ~30 degrees

Question 21

How do atmospheric circulation cells affect atmospheric pressure and rainfall patterns?

Answer 21

Rising air (low pressure) gets cooler and water vapor precipitates (wet climate). Sinking air (high pressure) has little moisture left in it (dry climate).

Question 22

Coriolis Effect (definition)

Answer 22

The eastward rotation of the earth causes moving air or water (or anything else) to be deflected to the right in the northern atmosphere (to the left in the southern hemisphere).

Question 23

___ generate surface winds across the ocean

Answer 23

Atmospheric circulation cells

Question 24

Climate (definition)

Answer 24

The overall average atmospheric conditions over many years

Question 25

Weather (definition)

Answer 25

Short term variable atmospheric conditions

Question 26

How does wind and the location of continents drive surface ocean currents?

Answer 26

Wind is the primary driver of surface currents. Trades push water west, which hits the continents and moves north, while westerlies push water back across the ocean.

Question 27

Ekman Transport (definition)

Answer 27

The transport of water at an angle to the wind due to the Coriolis effect. Net flow of water is to the right of the wind direction in the northern hemisphere.

Question 28

Gyres (definition)

Answer 28

Large areas defined by the currents flowing in a circular pattern

Question 29

5 main oceanic gyres

Answer 29

1) Indian
2) North Pacific
3) South Pacific
4) North Atlantic
5) South Atlantic