Ocean damage nearly doubles the cost of climate change

A groundbreaking study from researchers at the University of California, San Diego’s Scripps Institution of Oceanography reveals that the financial impact of greenhouse gas emissions is nearly twice as severe as previously estimated. This significant assessment introduces ocean damage into the social cost of carbon (SCC), a vital metric for quantifying the economic repercussions of climate change. The research indicates that losses in global coral reefs, disruptions to fisheries, and the devastation of coastal infrastructure amount to an astonishing $2 trillion each year. This revelation is poised to fundamentally alter the landscape of climate finance. Bernardo Bastien-Olvera, the study's lead author, emphasized the long-overlooked economic significance of ocean health. "For decades, we’ve been estimating the economic cost of climate change while effectively assigning a value of zero to the ocean," he stated. "Ocean loss is not just an environmental issue, but a central part of the economic story of climate change." The social cost of carbon serves as a crucial tool for estimating the monetary implications of each ton of carbon dioxide emitted. Amy Campbell, a climate advisor for the United Nations and former UK COP negotiator, highlighted its importance in integrating climate damages into economic decision-making. Historically, this metric has been utilized by various international organizations and U.S. federal agencies to evaluate policy proposals. However, a memo from the Trump administration in 2025 instructed federal agencies to disregard this data in cost-benefit analyses unless legally mandated. Campbell noted that determining which damages to consider can be contentious, as it raises questions about which sectors are included and how to value both current and historical harms. The previous social cost of carbon was pegged at $51 per ton of CO2 emitted. However, with the ocean's impact accounted for, this figure skyrockets to $97.20 per ton. Given that global CO2 emissions are projected at 41.6 billion tons in 2024, this revision represents a staggering 91 percent increase in estimated costs.