Ocean Acidification

pH

chemical measure of a concentration of p+ (proton) in a solution

describe pH trend

increase # of free protons pH drops, decrease free p+ pH increases (alkaline)

H₂0 ←> H⁺ + OH^-

water equation

describe the chemical aspect of natural buffer system

dissolved CO₂ + H₂O create → Carbonic acid (H₂CO₃) which is unstable in the ocean and causes the pH to drop

carbonic acid (H₂CO₃) dissociates creating Hydrogen ions (H⁺), leaving behind bicarbonate ions (HCO₃⁺)

a reaction of H⁺ ions and bicarbonate ions HCO₃^- creates/takes away carbonate ions CO₃^-2

descibe natural buffer system and how humans affect it

humans add carbon dioxide and make the ocean more acidic

this causes right (abundance of CO₂), the ocean naturally consumes the carbonate ions (CO₃^-2) and pushes the reaction to the left to balance the pH

since the ocean is using carbonates to balance the pH, the chemical is being taken away from organisms that use carbonate to create shells and disrupting food chains

what temperature of water dissolves gases better?

cold water

describe the oceans pH

• seawater is slightly alkaline

• pH decreases with depth

• upwelling (marine animal respiration) causes lower pH towards the surface

describe future estimates of ocean acidification

CO₂ will continue to increase

pH will continue to decrease

carbonates (CO₃^-2) will continue to decrease

what are the pH projections of the ocean?

in the next century it is projected that the ocean will have a pH of 7.6 - 7.9, the ocean isnt projected to turn into acid, it is only projected to turn more basic

describe ocean saturation state

carbonate concentrations are lowering (those of aragonite and calcite), if the concentrations become to low calcium carbonate dissolves

how CO₂ levels and Saturation affect organisms?

some species increase calcification, some decrease - this depends on if their shell has a protective organic coating (carbonates)

how does pH affect marine larvae?

larvae grown in a more acidic environment didn’t reach its full potential, and their growth was stunted

how does acidification effect pteropods

free-swimming sea snails aren’t being able to grow their shells due to not enough carbonate

how are pacific salmon food chain being disrupted?

their food source and food sources food source all need calcium carbonates to survive, since the levels are lowering the pacific salmon will not have a food source to eat because they all rely on carbonate to make a hard part

how will this lowering of carbonate affect Commerical fisheries?

shellfish and any organism that relies on carbonate to survive will no longer be living to be able to catch and make profit off of