Ocean Acidification

• Ocean acidification is the process in which seawater becomes more acidic because of the excess carbon dioxide (CO2) it is absorbing from the atmosphere. This phenomenon, which is impacting every ocean on Earth (as well as coastal estuaries and other waterways), is a direct consequence of the burning of fossil fuels and the resulting carbon pollution.

Causes of Ocean Acidification 

• When carbon dioxide dissolves into the ocean, it triggers a chemical reaction that increases acidity over time. More technically: CO2 and water produce carbonic acid, which releases hydrogen and bicarbonate ions. The more hydrogen ions there are, the more acidic the water becomes. This is what drives ocean acidification. 
• In addition to the burning of fossil fuels, another main culprit behind the sharp rise in ocean acidification is deforestation (both are major contributors to climate change). That’s because when a forest is cut or burnt down, it releases all of the carbon that was stored into the air.

Effects of Ocean Acidification 

• When CO2 dissolves into the ocean, it reduces the availability of carbonate: an essential building block for shellfish like mussels, clams, and oysters to create their protective shells and skeletons. Lower concentrations of carbonate in marine habitats therefore directly impact these animals’ chances of survival. If acidity were to rise high enough, seawater could literally dissolve shells. 
• Coral reefs also suffer the consequences. For example, Australia’s Great Barrier Reef has shown a 14 percent decline in calcification since 1990. Coral reefs are an essential part of marine ecosystems, providing shelter for 25 percent of marine species. These structures also protect coastal communities from erosion and storm sturges. Acidification is especially hard on reefs that already face natural bioerosion from the species of fish and worms that eat away at them. The reefs, which are famously slow-growing, can’t outpace this dissolution.
• The impacts of ocean acidification can ripple through the entire food chain, in water and on land.
• Significant portions of our economy rely on the ocean’s bounty in one way or another. 
• If ocean acidification is left unchecked, it is estimated that the industry can lose more than $400 million annually by the year 2100.

Solutions to ocean acidification 

• To advance the global transition to clean energy. Pollution regulations for power plants and stronger fuel-economy standards for our cars can help with that. Government leaders can also step up conservation efforts to protect and enhance the resilience of our forests, wetlands, and other critical carbon sinks, through initiatives like the 30x30 pledge, which sets aside 30 percent of our lands and waters to let ecosystems recover and withstand these growing challenges. Policymakers—recognizing the job sectors and other economic engines at risk from ocean acidification—are introducing climate action plans that promote increased investments in monitoring, forecasting, and mitigation.
• Considering the scale and rate of change, we need to prepare ourselves and safeguard vulnerable industries. “While ocean acidification’s effects have a global reach, local factors also influence how at risk regions are,” says Suatoni. Some managers of West Coast oyster hatcheries, for example, have invested in monitoring systems. When harmful acidic water upwells on the coast, they shut off their intake valves to prevent baby oysters from being exposed. Other solutions include cultivating ocean acidification–resistant strains of shellfish and diversifying aquaculture systems. For example,scientists are teaming up with fishermen to see how cultivating seaweeds like sugar kelp can potentially buffer farmed oysters, clams, and mussels from acidification as they absorb carbon dioxide from the salty water