Week 2

Question 1

What does studying oxygen tell us?

Answer 1

Photosynthesis produces oxygen, respiration consumes oxygen.
Can aid understanding of biological processes along various local and global circulation patterns

Question 2

What does studying helium/tritium tell us?

Answer 2

Underwater hydrothermal vents
How far from the source can we trace their plume? Can gain new information about ocean circulation.

Question 3

Input sources of Ions in the ocean

Answer 3

mainly from rivers and aerosols
lots of submarine groundwater discharge
minor hydrothermal systems

Question 4

Output sources of Ions in the ocean

Answer 4

mainly by evaporites and mineral formation
consumption of sediment at plate boundaries
minor from hydrothermal systems

Question 5

What are the main aerosol inputs?

Answer 5

Mineral dust (Al, Fe)
Important input of particles for some deep sea sediments (“red clays”)

Question 6

Is submarine groundwater discharge an input or output?

Answer 6

Mostly input, can be a very significant input ~40% of the river flux along eastern N.A. coast
definition: a mixture of fresh groundwater plus salty seawater recycles through coastal sediments

Question 7

Submarine groundwater discharge (SDG) is important for ______ cycling

Answer 7

carbon

Question 8

Hydrothermal processes at a high temperature are an input for which ions

Answer 8

Li+, K+, Rb+, Si 4+, Mn 2+, Ca 2+

Question 9

Hydrothermal processes at a low temperature are an input for which ions

Answer 9

Si and Ca

Question 10

Evaporites are a long term ____ of ____ from the ocean

Answer 10

output
salt

Question 11

Carbonate formation is a long term ____ of ____ from the ocean

Answer 11

output
Ca

Question 12

Hydrothermal processes at a high temperature are an output for which ions

Answer 12

Mg 2+ and SO4 2-

Question 13

Hydrothermal processes at a low temperature are an output for which ions

Answer 13

Mg 2+

Question 14

Dissolved organic matter (DOM) = ____ than ~1 um
Particulate organic matter (POM) = ____ than ~1 um

Answer 14

less
greater

Question 15

___ can sink, ____ mostly does not

Answer 15

POM
DOM

Question 16

The [K+] in two seawater samples are 10.0µM at location A and 10.5µM at location B.

What do you know about the relative salinity values from the waters at Location A and B? Why?

Answer 16

The salinity at A is lower than that at B, because K+ is a conservative element in seawater.

Question 17

This is a portrayal of deep water transport (blue arrow, ignore the orange arrow) in the global ocean. Nutrient concentrations (nitrate, phosphate and silicate) are highest in what ocean?

Answer 17

N. Pacific

Question 18

what is the process and equation responsible for the high nutrient content of water in the deep ocean?

Answer 18

respiration
organic matter + O2 –> CO2 + nutrients + energy

Question 19

Is silica a conservative or non-conservative element in seawater? Why?

Answer 19

It is not conservative, because it is involved in biological processes.

Question 20

What was the original use of DDT (dichlorodiphenyltrichloroethane)?

Answer 20

as a pesticide

Question 21

The use of DDT was banned world-wide because

Answer 21

It caused cancer in humans.
it caused death of fish, birds and other animals

Question 22

The origin of most anions in the ocean originally came from

Answer 22

volcanic gases

Question 23

An example of human input of elements to the ocean is

Answer 23

lead
cadmium

Question 24

Aerosol input to the oceans include

Answer 24

cosmic dust
mineral dust
volcanic ash

Question 25

The Mediterranean Sea dried up about 5 million years ago due to what cause?

Answer 25

closing of the Straits of Gibraltar, stopping exchange with ocean water

Question 26

What is the equation for calcite (CaCO3) production in seawater?

Answer 26

Ca2+ + 2CO3= –> CaCO3 + CO2

Question 27

What is the largest output of salts from the ocean?

Answer 27

evaporites

Question 28

What ions are output of seawater at high temperature hydrothermal vents?

Answer 28

Mg2+
SO4=

Question 29

Where do we get most of our salt used in cooking?

Answer 29

evaporite deposits