Study Finds Ocean Damage Nearly Doubles Cost of Carbon Emissions

A new scientific study has found that climate-related damage to the world’s oceans has been largely overlooked in economic assessments of carbon pollution, significantly underestimating its true cost. By factoring ocean impacts into climate models, researchers conclude that the societal cost of carbon emissions is far higher than previously calculated.

Led by scientists at the Scripps Institution of Oceanography, the study shows that oceans have absorbed much of the impact of rising carbon dioxide, including warming waters, acidification, and declining oxygen levels. These changes harm coral reefs, fisheries, and coastal infrastructure, while intensifying storm damage that affects trade, food supplies, and public health.

According to the findings, the social cost of carbon rises from $51 to $97.2 per metric ton when ocean damage is included, an increase of 91%. Researchers estimate that in 2024 alone, global carbon emissions caused nearly $2 trillion in ocean-related harm not reflected in standard cost estimates used by policymakers.

The study introduces the concept of a “blue” social cost of carbon to better capture both market and non-market losses, including reduced nutrition, tourism, and ecosystem value. Researchers say the approach could help governments and industries make more informed decisions, particularly for coastal and island communities facing disproportionate risks from ocean degradation.