OA CARBONATE CHEMISTRY

Question 1

what is ocean acidification? what damaging effects can it have to certain species?

Answer 1

the increase in dissolved CO2 leading to reduced pH in the ocean

can cause damage to molluscs and increase their vulnerability, also alters behaviour making them more evasive

Question 2

what were the direct and indirect effects of the industrial revolution/human impacts on ocean biogeochemistry?

Answer 2

direct effects - fluxes of material into the oceans
indirect effects - climate change and altered ocean circulation

Question 3

what are the sources and sinks of atmospheric CO2?

Answer 3

anthropogenic sources:
- burning of fossil fuels
- deforestation
- changes in land use
- energy and cement production

sinks:
- atmosphere
- oceans (20-35% of CO2 emissions)
- land

Question 4

how much % of CO2 emissions is taken up by the ocean?

Answer 4

20-35%

Question 5

how much % of CO2 emissions is taken up by the ocean?

Answer 5

20-35%

Question 6

what is the difference in atmospheric CO2 concentrations from the past 800,000 years compared to since the industrial revolution?

Answer 6

past 800,000 years: 172-290 ppmv
since IR: 280 to > 410 ppmv today

Question 7

what are the saturation state numbers for shell & skeletal formation (calcification; supersaturation) vs shell & skeletal dissolution (undersaturation)?

Answer 7

omega > 1 (supersaturation)
omega < 1 (undersaturation)

Question 8

what type of waters have higher CaCO3 saturation states? what type have lower saturation states? where is the effect of enhanced CO2 going to be more pronounced?

Answer 8

shallow, warm tropical waters
cold, high-latitude regions and at depth
colder, deeper regions are going to have more pronounced effects of enhanced CO2

Question 9

what factors does CO2 solubility depend on?

Answer 9

temperature, salinity and pressure

Question 10

what are the 2 main forms of CaCO3? which is more soluble?

Answer 10

aragonite and calcite- aragonite is more soluble than calcite

Question 11

SUMMARY
recent rates of rising atmospheric CO2 are … than historical changes
rising atmospheric CO2 concentrations are affecting the … … chemistry
natural buffering capacity of the oceans has … ocean pH at around …-…
imbalance in the natural … system due to rising CO2 means that pH is …, and the … saturation state is …
ocean pH and … saturation are affected by …, …, and … -> effects of high atmospheric … are more pronounced in … & … regions of the oceans
… is more soluble than …, which has implications for organisms that rely on … for … and … formation.

Answer 11

faster
ocean carbonate
maintained
8-8.1
carbonate
reducing
carbonate
declining
carbonate
temperature, salinity and pressure
CO2
colder
deeper
aragonite
calcite
aragonite
shell
skeletal