Learn more: What is the process of ocean acidification?

View all subject updates
Subject Update Learn More Ocean Acidification Process Figure 1
  1. Carbon dioxide in the atmosphere dissolves in the oceans.
  2. This aqueous carbon dioxide reacts with the water to form carbonic acid.
  3. The carbonic acid breaks down to form bicarbonate and hydrogen ions. The increase in hydrogen ions makes the oceans more acidic. So the more carbon dioxide that is absorbed by the oceans, the more acidic they become.
  4. Carbonate ions ‘buffer’ this increased number of hydrogen ions by forming more bicarbonate ions. Carbonate ions enter the oceans through processes such as the weathering of limestone (CaCO3). This buffering decreases the amount of carbonate and hydrogen ions in the oceans. Organisms that form their shells or skeletons from carbonate will be affected because there are fewer carbonate ions in the oceans.
  5. The levels of ocean acidification may also reach a ‘corrosive’ level where these shells or skeletons start to dissolve to ‘buffer’ the ocean pH.
Frozen Oceans Geography 14 16 Thumb

Geography | Ages 14-16

Frozen Oceans

This Frozen Oceans education resource includes two data case studies that introduce students to ocean acidification and sea ice thickness. The core of each case study are data sets from real expeditions.

Frozen Oceans Science 11 14 Thumb

Science | Ages 11-14

Frozen Oceans

The Frozen Oceans Science resources introduce working scientifically concepts and skills to 11-14-year-olds through enquiry-based lessons which replicate work done by field scientists in the Arctic.

Frozen Oceans Science 14 16 Thumb

Science | Ages 14-16

Frozen Oceans

This Frozen Oceans unit outlines the research carried out by the Catlin Arctic Surveys and can be used in teaching the carbon cycle, ocean acidification and its impact on the Arctic ecosystem.