Shell-Shocked Presentations

Causes of Ocean Acidification

  • Google Definition: “absorption of excess atmospheric carbon dioxide by the ocean”

  • Lead to lower PH levels,Carbonate Depletion,ocean warming, and nutrient pollution

  • When CO2 dissolves in seawater (H2O), it forms carbonic acid (H2CO3). This compound breaks apart, releasing hydrogen ions (H+) and bicarbonate ions (HCO3-)

  • Increasing carbon emissions have caused a jump in ocean acidification over the last few decades

  • Primary causes include burning of fossil fuels, deforestation and land use changes, and industrial production like cement production.

  • CO2 + H20= H2CO3

Past and Current Trends in CO2

  • Carbon dioxide have increased drastically due to large burning of fossil fuels, since 1700s 

  • CO2 has fluctuated between 200 to 8,000 ppm in last 550 million years. Early to middle Paleozoic, late Triassic, early Jurassic: highest

  • Dropped after Cretacious and have not been as high as today in last 800,000 years

  • The current carbon dioxide levels in our atmosphere is currently about 385 ppm

Creatures Responding Well to Increased CO2

Creatures Not Responding Well to Increased CO2

  • Conches and Quahogs are fine up to 900 ppm but then have a very negative response

  • Mollusks- (oysters, clams, bay scallops) fared the worst under increased CO2 conditions

  • Organisms that live in warm-water environments are not as adapted to acidic conditions, so they tend to fare worse

  • Temperate Corals

  • Pencil Urchins

Predictions for Future

  • There will be a decrease in population of shelled creatures like crabs, snails, and clams.

  • Clams and snails will have weaker shells which will make it easier for them to be hunted by crabs.

    • Crab population will increase then decrease

  • Critical points in carbon dioxide levels causes a rapid decline in the calcification of temperate corals, pencil urchins, quahogs, and bay scallops.

  • Increased ocean acidification would make it harder for the ocean to absorb carbon, making it less effective as a carbon sink

  • It is still unsure exactly what would happen however, due to a poor understanding of how sea organisms make their shells and skeletons.