Week 11 Ocean Acidification Flashcards
How much CO2 does the ocean absorb?
~25%
Why is Ocean Acidification: Climate Change’s “Evil Twin” ?
as atmospheric CO2 increases oceans absorb more of it making it acidic.
What are coral reefs?
ULTIMATE key stone species
provide underlying structure for reef communities.
Large underwater structures formed by colonies of invertebrae (corals) that produce calcium carbonate exoskeletons which accumulate over time.
approx 25% of all ocean species spend some portion of their lifetime in a coral reef.
Solubility pump of the ocean
*pCO2 reflects the amount of CO2 dissolved in the ocean
–> carbonic acid
–> bicarbonate release H+ ions –> carbonate
organisms consume dissolved CO2, biocarbonate acts as a store for CO2 in the ocean increasing pH.
T or F: Since the ocean carbon cycle can buffer
against changes in pH, we should not see any
change in seawater pH as a result of
anthropogenic input of CO2
False, increase in pCO2, will lead to decrease in pH rapid
solubility can’t buffer all of it.
Planetary boundary for ocean acidification
control variable:
Carbonate ion concentration, averaging global surface ocean saturation with respect to aragonite.
planetary boundary:
≥80% of the pre-industrial
aragonite saturation state of
mean surface ocean,
including natural and
seasonal variability
What is “Saturation State with respect to aragonite”?
Saturation state measures omega, the concentration of calcium carbonate (CaCO3-).
The mineral form of calcium carbonate is aragonite.
if omega <1 corrosive undersaturated
omega>1 ok oversaturated
Will the ocean always be able to take up
the excess atmospheric CO2?
as ocean acidity increases, the ability for it to absorb CO2 decreases.
solutions for ocean acidification?
restore/establish land uses that can absorb atmospheric CO2, like vegetation and soil.
geoengineering? putting iron in the ocean and human made phytoplankton blooms to take up CO2, only effective in small area and effects are unknown.
CUT FOSSIL FUEL EMISSIONS.
