Latest studies have shown that the ocean around New Zealand is getting more acidic.
The Stats NZ report, based on NIWA data, showed acidity has increased 8.6 percent between 1998 and 2020.
The danger is that a more acidic ocean may cause widespread harm to marine life.
It’s caused by the ocean absorbing carbon dioxide from the air, which can dissolve the shells of pāua, mussels and other kaimoana.
Around the world, ocean acidity has increased by 30 percent over the last 250 years, and will increase by up to 150 percent by the end of the century, Law said.