Ocean acidification, OA, has become an increasing problem for us. Ocean acidification is the continuing decrease in the pH of all our oceans. This is caused by extra carbon dioxide (CO2) which is absorbed by the ocean. This lowers the pH of seawater, which makes it more difficult for organisms like coral and shellfish to produce calcium carbonate shells. Carbon dioxide, CO2, is emitted when we burn fossil fuels, produce cement, or just simply breathe. Too much carbon dioxide can cause the greenhouse effect, which makes Earth and its atmosphere warmer. Carbon dioxide also can cause our oceans to become more acidic. This causes the pH (the measure of how basic or acidic a substance is) of the oceans to drop. Along with decreasing the oceans’ pH, the chemical reactions that occur when carbon dioxide is absorbed by the water reduce the amount of calcium carbonate minerals and carbonate ions in the water.Many ocean organisms, including coral, oysters, and shellfish, must produce calcium carbonate shells and skeletons. These organisms need carbonate ions and calcium carbonate minerals in order to form shells or skeletons. The decrease in both can make forming or maintaining these shells very difficult. Not only does ocean acidification make it much harder to make calcium carbonate structures, but when tested on pteropod shells, the very acidic water causes them to dissolve. The chance that many species will go extinct has increased, and many organisms will struggle to adapt to the changes in acidity. Reducing the amount of carbon dioxide in the air may seem like an impossible solution, but it can be done. If we were to burn fewer fossil fuels, then the amount of carbon dioxide would decrease dramatically. Sadly, humans rely on fossil fuels like coal and natural gas for electricity, transportation, and manufacturing products. Another way to reduce the amount of carbon dioxide emitted is by using less electricity. We all can take part in this by simply turning off the lights when leaving a room, taking shorter showers, or walking or biking short distances instead of driving. Instead of reducing carbon dioxide emissions, scientists have begun looking for other solutions in order to stop CO2 from getting into the ocean in the first place. In 2005, the Carbon Capture and Storage Association (CCSA) was formed. CCSA uses technology that captures carbon dioxide in the hope of reducing carbon dioxide emissions. In 2017, the company Climeworks built a carbon capture plant in Zürich, Switzerland. This carbon capture plant sucks in air and filters out CO2 into a pure form that is then sold, buried underground or made into other products. This is a form of carbon capture and storage, CCS, where carbon dioxide is captured and deposited in an area where it can not enter the atmosphere or oceans. All of us have a role to play in decreasing carbon dioxide emissions. Ways we can help are by planting more trees or preserving any existing forests. Overall, everybody can lend a hand in reducing the amount of carbon dioxide that enters our oceans and atmosphere. Ocean acidification, OA, affects our oceans and its animals. Unless we all participate in preventing more carbon dioxide from being absorbed into the ocean, many marine animals including coral and shellfish will be at the risk of extinction by 2100. The Carbon Capture and Storage Association (CCSA) will continue looking for more ways to reduce global carbon dioxide emissions and if we all take part in doing so, our oceans and its animals may still have a chance.