Scientists call it the "osteoporosis of the sea," a global spike in ocean acidity that eats away at coral reefs and damages other organisms necessary to sustain life in the near-shore oceans.
It is one of the lesser-known but hugely consequential impacts of climate change, and researchers this week will begin filling a major knowledge gap about the extent to which acidification is affecting the Indian Ocean, one of the richest marine environments in the world.
A panel of experts, including the State Department’s science envoy for the ocean and former NOAA administrator, Jane Lubchenco of Oregon State University, are meeting this week in Mauritius to advance new acidification monitoring efforts off the East African coast.
"A more corrosive ocean is a big problem for many shelled creatures such as oysters and crabs, but also coral reefs and more," Lubchenco said in an email exchange with ClimateWire from the island nation roughly 700 miles off Madagascar that is part of a volcanic chain called the Mascarene Islands.
"There is a growing, global network of scientists who are actively tracking and studying ocean acidification," Lubchenco added. "But this network has some huge gaps. The Indian Ocean off southern Africa is a big blank spot in our knowledge."
Scientists say ocean acidity, which has increased 30 percent over the last 150 years, is being advanced by large inputs of carbon dioxide into seawater. The absorption and breakdown of CO2 are altering the chemistry of the ocean, essentially driving down pH levels and subjecting marine life to elevated corrosive acid. Among the sea life most affected are organisms that make shells or skeletons from calcium carbonate, according to researchers.
The new monitoring effort — called ApHRICA — emerges from a new partnership between the State Department and a coalition of nonprofits, including the U.S.-based Ocean Foundation, the Heising-Simons Foundation, the XPRIZE Foundation, Schmidt Marine Technology Partners, Sunburst Sensors LLC and other research institutions.
The partnership will deploy pH sensors in the oceans of four countries — South Africa, Mozambique, the Seychelles and Mauritius — according to information provided by the State Department. This week’s workshop will focus on training African scientists "to contribute to the emerging knowledge about ocean acidification and help their countries understand the issues and options," Lubchenco said.
Mark Spalding, executive director of the Ocean Foundation, said the islands and coasts of the Indian Ocean "are as threatened by ocean acidification as any place else on the planet."
"Any plankton, clam, oyster, shellfish or coral polyp that forms a shell or reef is going to find that it expends much more effort to form that shell in a ocean that is now more acidic than ever before," he said in an email.
July has been a busy month for the State Department’s U.S. science envoys. In addition to Lubchenco’s work in Africa, other experts traveled recently to the Pacific Islands, Europe and Southeast Asia to help address environmental concerns from biodiversity and conservation to wildlife trafficking and the impact of development on natural resources.
