Week 4- Ocean acidification and atmospheric circulation

Question 1

Pteropods

Answer 1

Free-swimming sea snails
Potato chip of the sea
Imp source of food

Question 2

Ocean acidification

Answer 2

Significant and harmful consequence of excess carbon dioxide in the atmosphere and therefore excess amounts being absorbed by the ocean
(increased CO2 and decreased pH)

Question 3

How long does it take for the entire ocean system to become buffered?

Answer 3

1000 - 100,000 years

Question 4

Acidity

Answer 4

Conc of H+ in solution

Question 5

What happens ito pH f concentration of H+ increases

Answer 5

Decreases becoming more acidic

Question 6

What has happened to CO2 and pH since Industrial revolution?

Answer 6

30% of CO2 released into atmosphere has been absorbed by ocean
Ocean pH has decreased by 0.11 (30% increase in H+ conc)

Question 7

What does buffering do?

Answer 7

Prevents seawater from experiencing large changes in pH

Question 8

What is the equation for when seawater is too basic?

Answer 8

H2CO3———-HCO3- + H+
*pH drops

Question 9

What is the equation for when seawater is too acidic?

Answer 9

HCO3- + H+ ———- H2CO3
*pH rises

Question 10

When CO2 enters the ocean, what types of carbon does it create?

Answer 10

1. Bicarbonate ion (HCO3-)
2. Carbonate ion (CO3^2-)
3. Carbonic acid (H2CO3)

Question 11

OVERALL BUFFERING EQUATION

Answer 11

CO2 + H2O<==>H2CO3 <==> H+ + HCO3- <++> 2H+ + CO3^2-

Question 12

Calcite

Answer 12

• Varying amounts of MG2+ trigonal crystal system
• Stable state
• Plankton, sponges, brachiopods, echinoderms, bivalves (shell)
• High Mg and/or low Mg calcite

Question 13

Aragonite

Answer 13

• Orthorhombic crystal system
• Metastable state
• Greater solubility
• Corals, pteropods, molluscs
• All Mg

Question 14

What does buffering produce and what does it do?

Answer 14

Bicarbonate which moves pH towards neutral

Question 15

Why is the ocean not buffering?

Answer 15

Buffering can’t keep up with the speed at which CO2 is changing the oceans pH

Question 16

Effects of ocean acidification on calcifiers

Answer 16

• Difficult for organsims to create hard parts and requires more energy
• Calcifiers have smaller shell sizes, more fragile shells, dissolving shells, low reproductive rates

Question 17

Effect of ocean acidification on byssal threads

Answer 17

Becoming weaker

Question 18

Effects of ocean acidification on all organisms

Answer 18

• Loss of biodiversity
• Affects food security
• $$ loss
• Loss of coastal protection
• Decrease in ocean’s ability to absorb CO2