A peer-reviewed study published in Nature Climate Change has put a price tag on what its authors call the “big missing piece” in climate economics: the ocean. By calculating the damage that rising temperatures inflict on corals, mangroves, fisheries, seaports, and mariculture, the research finds that standard estimates of carbon’s economic toll have been roughly half of what they should be. The finding arrives as separate assessments warn that trillions of dollars in global output depend on natural systems that businesses and governments still largely treat as free.
What the Social Cost of Carbon Leaves Out
Governments and regulators rely on a metric called the Social Cost of Carbon, or SCC, to weigh the economic damage of each additional ton of CO2 released into the atmosphere. That number shapes everything from vehicle-emission standards to power-plant regulations. Yet the models feeding those estimates have a well-documented blind spot. A 2017 report by the National Academies laid out a framework for updating SCC calculations, noting that model architecture, damage functions, and discounting methods all needed revision. In the years since, the science has moved considerably faster than the policy.
A 2022 paper in Nature used the open-source GIVE model to recalculate the SCC with updated probabilistic projections and damage functions, arriving at a mean estimate of roughly $185 per ton of CO2 under a 2% near-term risk-free discount rate. That figure was already far higher than the numbers most governments use. But even that calculation did not account for what happens beneath and along the world’s coastlines, an omission the latest Nature Climate Change paper now addresses head-on. The result is a growing recognition that climate damages are not only broader than once assumed, but also more tightly linked to specific ecosystems that underpin economic activity.
Ocean Damage Nearly Doubles the Price Tag
The new study, published in Nature Climate Change, introduces what the authors term a “blue SCC.” It quantifies climate impacts on five categories of ocean and coastal capital: coral reefs, mangrove forests, seaports, wild fisheries, and mariculture operations. These sectors had been largely excluded from the integrated assessment models that produce standard SCC figures. The researchers estimate the blue SCC at about $48 per ton of CO2 in 2020, with an interquartile range of $38 to $70. When layered on top of the existing land-focused estimate of $51 per ton, the combined figure reaches $97.2 per ton, representing an approximately 91% increase in the estimated damage from each ton of emissions.
That near-doubling is not a speculative projection. The underlying analysis is archived on Zenodo, and the climate-economy model code used to run the calculations is available in a separate tagged repository, allowing independent researchers to reproduce the $48 per ton estimate and inspect every assumption. This level of transparency matters because the SCC is not an academic curiosity, it directly determines how aggressively regulators justify climate rules and infrastructure investments. A higher SCC means stronger economic rationale for cutting emissions, and a lower one gives industries more room to argue that compliance costs outweigh benefits. The ocean, in other words, is not just an ecological concern here. It is a missing variable in the math that shapes trillion-dollar policy decisions and long-lived assets along coasts worldwide.
Nature as Economic Infrastructure
The ocean findings sit within a broader pattern of undervaluation. The World Economic Forum estimates that roughly half of global GDP, or about $44 trillion of economic value, depends on nature in some form. That includes agriculture, forestry, and fisheries, but also supply chains, real estate, and tourism that rely on functioning ecosystems. When coral reefs degrade, coastal tourism and fisheries revenues collapse. When mangroves disappear, storm-surge damage to ports and coastal property rises. These are not abstract risks, they show up in insurance claims, commodity prices, and municipal budgets, often long before they appear in national statistics or corporate disclosures.
Yet most businesses still do not account for these dependencies. A February 2026 assessment highlighted by the European Commission found that many companies overlook nature-related risks, even as global science points to a growing finance gap for conservation and restoration. The report exposed structural challenges in how firms assess and disclose their exposure to ecosystem decline, from fragmented data to inconsistent methodologies. Without standardized measurement, the financial system effectively prices nature at zero, which means capital flows toward activities that degrade it without any market signal pushing back. The blue SCC work underscores that this is not just an environmental blind spot but a mispricing of risk and value that reverberates through credit markets and public balance sheets.
Why Current Policy Models Fall Short
The most striking takeaway from this body of research is not any single number but the pattern it reveals. Each time scientists update their models to include a previously ignored category of damage, the estimated cost of carbon jumps significantly. The National Academies flagged the need for better damage functions nearly a decade ago, warning that omitting key sectors would bias results. The 2022 Nature study showed that updated methods and probabilistic projections pushed the SCC to $185 per ton, far above prevailing policy benchmarks. Now the blue SCC adds another $48 per ton on top of a baseline that was already too low. The direction is consistent: we have been systematically undercounting the bill, especially for communities and industries tied to coasts and marine resources.
This matters in practical terms because the SCC feeds directly into cost–benefit analyses for regulations, public investments, and even litigation over climate damages. If the ocean component alone adds roughly $46 per ton to the damage estimate relative to a $51 benchmark, then every rule that was justified at the old, lower number may be insufficiently stringent when the full costs are counted. Policies that once appeared marginal on economic grounds (such as accelerated coal retirements, stricter efficiency standards, or expanded marine protection) can look clearly beneficial under a higher SCC. Conversely, projects that depend on cheap fossil fuels or vulnerable coastal infrastructure may no longer pass a rigorous economic test once ocean and nature-related damages are included. The gap between what models capture and what ecosystems actually contribute is therefore not just a technical detail; it is a central fault line in climate and economic policy.
Integrating Ocean and Nature Risks Into Decisions
The emerging research on ocean damages points toward several concrete shifts in how governments and markets could operate. First, regulators can explicitly incorporate a blue SCC into formal rulemaking, either by adjusting headline SCC values upward or by adding a documented ocean component in parallel. Because the underlying data and code are openly accessible, agencies and independent analysts can stress-test the assumptions and tailor them to national circumstances without starting from scratch. Second, climate-risk assessments for coastal infrastructure (from ports and naval bases to desalination plants and tourism hubs) can treat coral reefs and mangroves as protective assets whose degradation carries quantifiable economic costs, rather than as scenic backdrops. This would bring environmental impact assessments closer to the reality that ecosystems function as infrastructure.
Financial institutions, meanwhile, are beginning to face pressure from investors and regulators to align portfolios with nature-positive outcomes, but the tools remain rudimentary. Integrating metrics derived from studies like the blue SCC into scenario analysis could help banks, insurers, and asset managers understand how ocean degradation affects loan performance, insured losses, and long-term asset values. For companies, aligning with emerging disclosure frameworks on nature-related risk will likely require moving beyond qualitative statements to quantitative estimates grounded in peer-reviewed science. The growing body of open, reproducible climate–economy research offers a path to do that. The central message running through these developments is that oceans and ecosystems are not external to the economy; they are part of its core capital stock, and ignoring their decline leads to systematic underinvestment in resilience and emissions cuts.
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*This article was researched with the help of AI, with human editors creating the final content.
