Acidification of the Ocean

Deep sea sequestering

• Storing CO2 in the sea• Less CO2 in the atmosphere• Acidifies the Ocean • Dangerous for marine life

Acidification of sea water Lab

• Aim: State the pH sea, and compare the results of the pH values of the variety of waters with those affected by CO2.

• This is to show how CO2 affects the pH scale of seawater.

• Seawater is slightly alkaline, therefore we will start out with a blue color shown by the pH indicator.

Acidification of seawater

Results

• The seawater becomes lighter.• Indicating that the seawater becomes more

acidic if CO2 is added.

Effects on marine life• The dissolution of carbon dioxide in sea water makes it more acidic. • a decrease in a very important form of inorganic carbon: the carbonate ion (CO32-).• Numerous marine organisms such as corals, mollusks, crustaceans and sea urchins

rely on carbonate ions to form their calcareous shells or skeletons in a process known as calcification.

• The concentration of carbonate ions in the ocean largely determines whether there is dissolution or precipitation of aragonite and calcite, the two natural polymorphs of calcium carbonate (CaCO3), secreted in the form of shells or skeletons by these organisms.

• Today, surface waters are supersaturated with respect to aragonite and calcite, meaning that carbonate ions are abundant.

• This super saturation is essential, not only for calcifying organisms to produce their skeletons or shells, but also to keep these structures intact. Existing shells and skeletons might dissolve if pH reaches lower values, and the oceans turn corrosive for these organisms.