On Samui Island in Thailand, many households spend more than half their income on petrofuel to provide fish for their families. The global atmospheric concentration of CO2 has increased, w corresponding CO2 dissolution in oceans. This has resulted in a present day 30% increase in ocean acidity, a rate of change ~100x more rapid than any in 100,000 years, leaving little to no time for evolutionary adaptation to changes in ocean chemistry by marine organisms. Ocean acidification is irreversible on short (x100yr) timeframes. It can be predicted with a high level of certainty that current fossil fuel based emissions will lead to a 150-185% increase in acidity by 2100. Ocean acidification is expected to have major negative impacts on corals & marine organisms that build CaCO3 skeletons and shells, w concern especially high in polar regions where saturation states are naturally low. A corresponding decrease in fishing revenues & significant impacts for communities that depend on the resources for income and livelihoods is anticipated.Ocean acidification-driven declines in commercial shellfish and crustacean harvests to 2060 estimate a decrease U.S. primary commercial revenues between US$860 million to US$14 billion, depending on CO2 emissions, discount rates, biological responses and fishery structure.