Intro to marine systems

Question 1

t/f
the arctic ocean is shallow and very cold

Answer 1

false

deep and cold!

Question 2

water mass=

Answer 2

a large volume of water with unique properties of temp, salinity, and density that extends over 1000s of km

Question 3

How do you measure a water mass?

Answer 3

CTD rosettes

(CTD= conductivity, temp, depth)

Question 4

All oceans are structured by water masses, and there are 3 water masses in the Canada Basin of the Arctic Ocean:
1
2
3

Answer 4

1. Arctic/ polar water
2. Atlantic water
3. bottom water

Question 5

Explain the process of brine rejection

Answer 5

as the surface of the ocean cools, ice forms and as the ice continues to develop, salt is ejected from the growing ice = brine rejection

Question 6

brine rejection is a major process in driving the ocean ___

Answer 6

currents!

Question 7

Northward flowing ___ water is the major means of head advection toward the arctic and strongly affects the ___-___ distribution

Answer 7

atlantic
sea-ice

Question 8

t/f

Atlantic waters entering the Arctic ocean have always been close to the temperature they are today

Answer 8

false

temps of atlantic water are unprecedentedly high compared to past 2000yrs, & are linked to arctic amplification of global warming

Question 9

There are 3 components of an arctic marine habitat:
1
2
3

Answer 9

1. ice-covered seas
2. open seas
3. benthic habitats

Question 10

What is a floe? List 3-6 defining characteristics

Answer 10

A floe is a piece of sea ice (acts like a sailboat, the ridges act as sails!)

1. floe size
2. source (fresh/ salt water)
3. form (attached to land/ drifting)
4. development/ age
5. deformation
6. ice cover

Question 11

Freeboard=
Draft=

Answer 11

Freeboard= part of the ice floe above the water surface (w/o snow)

draft= part of the ice floe below the water surface

Question 12

What is the melt pond depth? Melt pond bottom Z coordinate?

Answer 12

melt pond depth= max depth of a melt pond on an ice floe

melt pond bottom z coordinate= distance b/w the water surface and the bottom of the melt pond

Question 13

multiyear ice is biologically ____ (productive or unproductive)? Why?

Answer 13

unproductive

b/c there’s no light penetration

Question 14

• sea ice expanded from the central arctic ocean for the first time __ million years ago
• Sea ice expanded more in response to positive ice-___ feedback mechanisms

Answer 14

4

albedo

Question 15

sea ice provides a series of specialized ___ for many species

Answer 15

niches

Question 16

Over time, sea ice deforms. What are the progressions over time?

Answer 16

Rafted ice –> Pressure ridges –> weather ridge –> hummocks

Question 17

____ ___ formation is essential for ringed seal lairs for giving birth to pups

Answer 17

pressure ridges

Question 18

Polynya=

Answer 18

= area of open marine water at high latitude that remains ice free throughout the years (b/c of currents, tides, upwellings, winds)

Question 19

2 reasons polynyas are important:

Answer 19

• important over-wintering areas for many species (rely on polynyas to breath etc, and utilize ice around them)
• plays a major role in organization of marine life in the arctic

Question 20

How many major polynyas are there in the circumpolar arctic?

Answer 20

6

Question 21

Coastal polynyas (ie ___ heat polynyas) are driven by ____ ____

Answer 21

latent

land winds

Question 22

open ocean (ie __ heat) polynyas stay as open water b/c cold dense water sinks deeper, pushing up relatively ___ water

Answer 22

sensible heat

warm

Question 23

What’s a major source of the world’s bottom waters?

Answer 23

when salt is released (brine formation) from sea ice –> the cold saltier waters sinks, becoming bottom water

Question 24

The community that occurs under sea ice is called ____

Answer 24

epontic

eg. “epontic algae”

Question 25

Estuaries=

Answer 25

open sea habitat where water is coming in from rivers etc

Question 26

Estuaries have high ___ loads meaning low light ____

Answer 26

sediment penetration

Question 27

Give an example of estuaries being utilized by marine animals?

Answer 27

belugas come to estuaries in the high Canadian arctic in late summer- they rub on the mud/ limestone bottom to remove their epidermis (moult)

Question 28

belugas are ____, and in the spring/ summer they come to ___ - why?

Answer 28

migratory estuaries - to moult, maybe to avoid predators or thermal advantage

Question 29

t/f belugas are well adapted to changing their migratory patterns based on ice availability

Answer 29

true, this is an advantage with climate change!

Question 30

benthic species =

Answer 30

species that live/ feed @ ocean bottom

Question 31

littoral zone=

Answer 31

aka intertidal zone - special part of the benthic biotope that's part of the coast b/w the lowest ebb tides and highest high tide

Question 32

pelagic species =

Answer 32

species that live and feed in the water column

Question 33

epontic species=

Answer 33

species that live on the underside of sea ice