Ocean Acidification

Fossil fuels are notoriously known as a significant environmental stressor and leading factor of climate change. The burning of fossil fuel releases greenhouse gasses into our atmosphere. Including Carbon Dioxide, the most significantly impactful GHG linked to global warming. The burning of fossil fuels refers to the burning of oil, coal and natural gas in order to generate energy such as electricity and heating.

Our ocean absorbs a significantly large portion of carbon dioxide, which is released into the atmosphere both naturally and un-naturally due to human-induced factors. Primarily, increased Carbon Dioxide absorbed by the ocean decreases the oceans pH levels and slowly turns the water acidic. When CO2 enters the water, a series of chemical reactions occur resulting in a heightened concentration of hydrogen ions. This unbalance presents unparalleled threats of acidification to ocean marine life and surrounding habitat.

Ocean acidification is a serious threat to Canadian waters, with Canada’s oceans becoming more acidic each year. Ocean acidification began as a result of the Industrial Revolution, with about one quarter of the carbon dioxide (CO2) produced being absorbed by our oceans. With so much additional CO2, the chemistry of the oceans’ have changed and become more acidic with decreasing pH.

With the chemistry of the ocean changing, oceanic species have needed to adapt quickly as ocean acidification has made it very difficult for many species to survive. Species such as mussels and lobsters, who use calcium carbonate to form their shells, need to use more energy to build their shells once the ocean becomes more acidic. This has drastic impacts on marine food webs as organisms at the base of the food chain (ex. zooplankton) cannot survive or adapt quickly enough to the impacts of ocean acidification.

Canadian coasts are particularly prone to ocean acidification. Coastal waters are more vulnerable since CO2 is more readily absorbed in colder waters, as well as in increased undersaturated waters at shallow depths like in the Pacific coast and large freshwater influxes like in the Arctic coast. Freshwater runoff and ice melt is also important to consider as they can reduce the ocean’s ability to buffer against changes in pH – increasing the chances of acidification.

Without healthy oceans and dynamic food webs, coastal communities will greatly suffer. As the ocean continues to change, we need to continue finding new ways to adapt and help coastal communities become more resilient against the impacts of ocean acidification.