NOAA’s Pacific Marine Environmental Laboratory (PMEL) Carbon Dioxide Program maintains a site that’s chock-a-block with info about the ocean carbon cycle, including acidification. Technical language, but accessible to the lay person.
"The ocean plays a critical role in the global carbon cycle as avast reservoir that exchanges carbon rapidly with the atmosphere, andtakes up a substantial portion of anthropogenically-released carbonfrom the atmosphere. A significant impetus for carbon cycle researchover the past several decades has been to achieve a betterunderstanding of the oceans’s [sp] role as a sink for anthropogenic CO."
"Anthropogenically-released carbon" means the carbon dioxide humans produce by burning fossil fuel, or any other human-related endeavor.