Oceanography

Question 1

what is thermocline?

Answer 1

the thermocline is the transition layer between surface layer and bottom layer. (temperature)

Question 2

what is the halocline?

Answer 2

the halocline is the transition layer between fresh water and salt water

Question 3

what is the measurement for salinity?

Answer 3

ppt–parts per thousand

Question 4

what is salinity? how much salt is in the ocean?

Answer 4

salinity is the measure of salt dissolved in water.

3.5% or 35ppt = salinity in ocean

Question 5

what is upwelling? what does it bring up?

Answer 5

wind blows water and then cold water rises. that water brings up fish and food.

Question 6

what is downwelling? what does it bring down?

Answer 6

water goes downward. brings down oxygen, food, heat

Question 7

why does ice float?

Answer 7

ice freezes and then expands. the way ice freezes is water molecules create a 102 degree angle which creates the crystal shape. then the crystal shape causes it to expand. it is less dense than water.

Question 8

what temperature is water most dense at?

Answer 8

4 degrees Celsius

Question 9

how can you increase density of sea water?

Answer 9

by taking away fresh water.

evaporation and freezing

Question 10

how can you decrease the density of sea water?

Answer 10

by adding more fresh water.

water melts from LAND, rain/snow, rivers

Question 11

what is oceanography?

Answer 11

study/ mapping of the ocean floor

Question 12

how is the water distributed in the world?

Answer 12

97%=saltwater: oceans

3%=freshwater: ice caps, rivers, lakes, underground

Question 13

what are 3 ways sea levels change?

Answer 13

temperature, plate tectonics, melting ice

Question 14

how does temperature affect sea levels?

Answer 14

when temp rises, water expands, sea level rises.

when temp falls, water condenses, seal level falls.

Question 15

how does plate tectonics affect sea levels?

Answer 15

rising and falling of the sea floor

Question 16

how does melting ice affect sea levels?

Answer 16

when ice from land masses melt, goes into ocean, level rises.
when ice forms on land, takes away from ocean, level drops

Question 17

how much of the world is covered by oceans?

Answer 17

71%

Question 18

list the 5 oceans by size

Answer 18

Pacific, Atlantic, Indian, Antarctic, Arctic

Question 19

which ocean is shrinking? why?

Answer 19

Pacific; because of subduction zones, the continents are getting pushed together

Question 20

which ocean is growing? why?

Answer 20

Atlantic; because of mid oceanic ridge, new sea floor

Question 21

what is the new ocean?

Answer 21

Ethiopian ocean, 10 million years is expected

Question 22

what are the 3 characteristics a body of water needs to be classified as a sea?

Answer 22

partially/mostly land locked
saltwater
part of water (ocean) circulation

Question 23

how is water a good buffer?

Answer 23

water stores heat. it absorbs heat during day and releases it at night. this allows for less drastic temp swings

Question 24

what is a salt? what is most common salt in ocean?

Answer 24

a metal + a non metal

NaCl is most common in ocean

Question 25

what is the density of sea water?

Answer 25

1.02 - 1.03 g/cm3

Question 26

how is the density of oceans affected?

Answer 26

by temperature and salinity

Question 27

how far can light travel in the ocean? and what light goes farthest?

Answer 27

100 meters.

red is absorbed first, blue goes farthest

Question 28

no surface layer = ?

Answer 28

no thermocline

Question 29

Gyers do not cross the ___

Answer 29

equator

Question 30

gyers in the northern hemisphere move ____

gyers in the southern hemishpers move ____

Answer 30

northern= clockwise/right
southern= counterclockwise/left

Question 31

what do gyers move around?

Answer 31

heat

Question 32

what is the longest mountain ridge on Earth?

Answer 32

the mid Atlantic ridge

Question 33

where does the hydrothermal vent get its heat?

Answer 33

earth’s mantle/magma

Question 34

when did oceanography begin and what was the first vessel to explore the ocean floor?

Answer 34

began in late 1800s

The Challenger

Question 35

ocean temps can very from ___

Answer 35

-2 to 35 degrees Celsius

Question 36

land temps can vary from ___

Answer 36

-70 to 35 degrees Celsius

Question 37

Water becomes denser until ___ and then ___

Answer 37

4 degrees C ; expands

Question 38

In the Pacific, the ridge is ___ faster than new floor created which means the ocean is getting ___

Answer 38

subducting, smaller

Question 39

what is the salinity in the subtropical and why?

Answer 39

37ppt; increased evaporation increases salt ions

Question 40

what is the salinity in the tropics and why?

Answer 40

32-33ppt; lots of rain= more fresh water

Question 41

salt water freezes at ___

Answer 41

-2 degrees Celsius because takes more energy to freeze salt ions

Question 42

ancient seas and todays seas have same salt levels. how do we know?

Answer 42

evidence found in old and new sea shells and fossils

Question 43

what creates the densest sea water?

Answer 43

high salinity + cold temp = densest water

Question 44

water ___, leaves behind ___, cold water sinks beneath ice and becomes ___ and ___, then ___ and migrates to the ___

Answer 44

freezes, salt, saltier, denser, sinks, equator

Question 45

why do gyers not cross the equator?

Answer 45

because southern and northern hemisphere currents are opposite

Question 46

where the sea floor drops off quickly?

Answer 46

slope

Question 47

what is the flattest part of earth?

Answer 47

abyssal plains