The global cost of greenhouse gas emissions is nearly double previous estimates, according to a study published Thursday by researchers at the University of California, San Diego's Scripps Institution of Oceanography. The study, which factors in damages to the ocean for the first time in a social cost of carbon (SCC) assessment, estimates that global coral loss, fisheries disruption, and coastal infrastructure destruction cost nearly $2 trillion annually. This new calculation significantly alters the understanding of climate finance and its economic impact.

The social cost of carbon is a metric used to determine the monetary cost of each ton of carbon dioxide released into the atmosphere. According to the study, the previous SCC assessments effectively assigned a value of zero to the ocean, leading to a significant underestimation of the true economic impact of climate change.

"For decades, we've been estimating the economic cost of climate change while effectively assigning a value of zero to the ocean," said Bernardo Bastien-Olvera, who led the study during his postdoctoral fellowship at Scripps. "Ocean loss is not just an environmental issue, but a central part of the economic story of climate change."

The inclusion of ocean-related damages in the SCC assessment has significant implications for policy decisions and market valuations. The $2 trillion annual cost encompasses a range of factors, including the decline in fisheries yields, the destruction of coastal properties due to rising sea levels and extreme weather events, and the loss of coral reefs, which provide vital ecosystem services and support tourism industries.

The revised SCC could influence investment strategies, as companies and investors increasingly factor in the financial risks associated with climate change. Industries reliant on healthy ocean ecosystems, such as seafood, tourism, and shipping, may face increased pressure to adopt more sustainable practices. Governments may also be compelled to implement stricter environmental regulations and invest in coastal protection measures.

The study's findings highlight the interconnectedness of the global economy and the environment. By incorporating the economic value of the ocean into climate change assessments, researchers aim to provide a more accurate and comprehensive picture of the true cost of greenhouse gas emissions. The updated SCC could lead to more effective climate policies and a greater emphasis on protecting marine ecosystems.