Oceans - Ocean Acidification Kwongs side Flashcards
How much anthropogenic CO2 has been absorbed by oceans?
30% in the last 250 years
How are oceans important?
- Regulate concentration of CO2 in atmosphere
- Reduce rapid rise in temperature
How does global warming affect the role of the ocean in the global carbon cycle?
- As surface water temperature rises the ability of water to absorb CO2 reduces
What is ocean acidification?
- CO2 from the atmosphere is absorbed by oceans where it reacts with sea water to form carbonic acid
How much has acidity increased by since pre-industrial levels?
30%
What is formed from the carbonic acid?
Calcium bicarbonate
Why is it difficult for organisms to build their shells?
- carbonate concentration are diluted
Where is ocean acidification likely to increase the most?
- Arctic Ocean -> cold polar regions
What effect does ocean acidification have on microscopic plankton?
- Dissolves calcium carbonate shells, reduce resilience, reduce pop.
What effect does impacts on microscopic plankton have?
- Affect food supply for consumers and impacts food web
What uses calcium carbonate to build its shells or skeletons?
- Molluscs
- Crustacea
- Corals
What trophic level is susceptible to predation?
Lower
What will happen if lower trophic levels reduce in number?
Higher trophic levels are put at risk
Why are sea butterflies important?
- Significant food source for krill
- Food source for herring mackerel
- Base of the food web
What do sea butterflies feed on?
Plankton
Where are sea butterflies found?
Poles to tropics
What marine animals are at risk due to acidic waters?
Shell
Where have massive die-offs of oysters been received?
- US
- Pacific NW
Why do mussels face additional risk?
The use thread like material to cling onto rocks -> less effective in acidic water
What specie benefit from ocean acidification?
- Shellfish
- Diatoms silica shells
Why will jellyfish thrive in these conditions?
- Pop. increase more -> competition with other predators for small fish disturbing equilibrium
Who will not be affected by ocean acidification?
Diatom (algae)
How much seafood produced annually?
200 million tonnes
Which countries depend on seafood for diets?
- Fiji
- The Gambia
- Bangladesh
Why are small island states threatened?
- Limited agriculture alternative
- Food insecurity
Why is competition in the marine ecosystem increased?
Some predatory species switch prey
