What about the ocean?

Climate change alters the acidity of the ocean, and a powerful alliance of government agencies, including the U.S. Navy, National Oceanic and Atmospheric Administration (NOAA) and the U.S. Fish and Wildlife Service, has joined together to take action.(1),(2)

These agencies found that the acidity of the oceans has increased roughly 30 percent since the 19th century. That change is 10 times faster than at any other point in human history.(3) This issue could hugely affect human wellbeing since more than 3.5 billion people rely on the ocean as their primary food source.(4)

“This is a very dramatic change that has not been seen in world oceans for more than 50 million years.”
— Dr. Richard Feely, NOAA Senior Scientist

“The growing amount of carbon dioxide in the ocean could have a bigger effect on life on Earth than carbon dioxide in the atmosphere.”

— Dr. Charles Miller, NASA Research Scientist

For over a century, people have emitted greenhouse gases into the air and disrupted the natural carbon cycle. The extra CO2 is having immediate and measurable changes on the chemical makeup of oceans.(7)

U.S. Agencies Partner to Study and Prevent Ocean Acidification


Source: Modified from a chart in the Bulletin of the American Meteorological Society, July 2008

According to NOAA, oceans took in roughly a quarter of all the carbon dioxide (CO2) related to human activities since the 1800s. The CO2 turns the water into carbonic acid as it’s absorbed.(5) Every year, about 2 billion metric tons of carbon go into the world’s waters – the equivalent of 11 million railroad cars filled with coal. These cars could form a train long enough to circle the Earth 14 times.(6)


Source: NOAA

Carbon dioxide’s destructive effect under the sea
As CO2 enters the ocean, it acidifies seawater by forming carbonic acid – the same carbonic acid that gives soda bubbles (think “carbonation”). This acidic water dissolves the chalk-like shells and skeletons of coral, shellfish and fish.(8) Ocean acidification can lead to large aquatic die-offs.(9)


Source: National Geographic

Scientists believe the ocean’s acidity will only keep increasing. In the above photos, a sea snail’s shell was placed in seawater artificially brought to the same acidity that researchers predict our oceans will have by 2100. The shell slowly dissolves over just 45 days.(8)



  1. NOAA: OAP Interagency Engagement
  2. NOAA: What Is Ocean Acidification?
  3. NOAA: State of the Science Fact Sheet
  4. Reuters
  5. NOAA: The Other Carbon Dioxide Problem
  6. NOAA: OAP’s What Is Ocean Acidification
  7. NASA: Climate Change Seeps into the Sea
  8. NOAA: The Chemistry
  9. World Bank


  1. Carbon Emissions Changing Ocean Chemistry – NOAA: What Is Ocean Acidification (OA)?
  2. Atmospheric and Ocean Carbon Dioxide vs. Ocean pH – NOAA: Hawaii Carbon Dioxide Time-Series
  3. Shell over 45 Days – David Liittschwager via National Geographic