Hydrosphere 1 session 1

Question 1

What are the connections between the hydrosphere and lithosphere?

Answer 1

Continental weathering and erosion
Hydrothermal inputs/ seafloor weathering
Seafloor sedimentation
Sea spray (salt)

Question 2

What are the connections between the atmosphere and hydrosphere?

Answer 2

Gas exchange
Sea spray and aerosol production
Evaporation/Rain

Question 3

Why does gas exchange occur between the atmosphere and ocean?

Answer 3

Concentration gradient between the surface ocean which will want to make things equal

Question 4

How does temperature affect gas exchange?

Answer 4

colder water can hold more then hotter

Question 5

How does sea spray aerosol production occur?

Answer 5

surface bubble which chemicals gather on film of and then run down bubble into the water,
bubble top pops and sprays up

Question 6

What are the links between the hydrosphere and cryosphere?

Answer 6

Glacial weathering
Freezing/ melting

Question 7

What is the link between the hydrosphere and the biosphere?

Answer 7

Photosynthesis- biomass growth
Death/ decay

Question 8

What is the composition of salts in sea water?

Answer 8

Predominantly chloride and sodium
Important are minor constituents control where and what can grow

Question 9

What is the proportion of water to salt like in sea water?

Answer 9

96.5% water
3.5% salt

Question 10

What is the PPT (parts per million) of salt in ocean?

Answer 10

35

Question 11

How does thermohaline circulation occur?

Answer 11

equator heated by sun warm water rises and more dense water fills gap
Warm water travels to poles where made cold and denser so sinks but salt cant freeze so water made even more dense

Question 12

What are the local controls on ocean salinity?

Answer 12

Evaporation (increased saltiness)
Precipitation (decreased saltiness)
Inflow (decreased saltiness)
Outflow (increased saltiness)

Question 13

How does deep water form?

Answer 13

when surface ocean is dense (cold and salty)

Question 14

What is the residence time?

Answer 14

the time matter will remain locked in a stored before being transferred by a flux

Question 15

How long did it take to make the oceans salty (to present levels)?

Answer 15

with present salt content and river solid addition/ river input mathematically only 20 million years but we know ocean is 3.5-4 billion years old so must be salt removing processes

Question 16

What does mass balance state over time?

Answer 16

sources (ins) must equal sinks (outs)

Question 17

How is salinity delivered to oceans?

Answer 17

by rivers

Question 18

How does salinity leave the ocean?

Answer 18

as evaporated salt deposits in isolated basins where evaporation is greater than precipitation

Question 19

What shows that river water isnt the only source of saltiness in the oceans?

Answer 19

the fact that the chemical composition of river water and ocean water is different.

Question 20

Besides rivers what is another sources of saltiness in the oceans?

Answer 20

Deep sea vents and volcanic exchange of fluids and heat between litho and hydro

Question 21

What are the residence times of the major ocean ions?

Answer 21

Sodium: 68 million years
Chloride: 100 million years
Magnesium 10 million years
Sulphate 10 million years
Potassium: 7 million years
Calcium: 1 million years
Iron: 50 years