Climate Report Says Cost of Emissions Far Worse Than Thought

Past emissions have already committed the planet to higher temperatures, rising seas and other long-term damage, and the economic bill for that damage is bigger than previously understood. That is the central message of the 2026/2027 edition of "10 New Insights in Climate Science", published October 6 by a team of more than 70 scientists from nearly 30 countries. According to the Potsdam Institute for Climate Impact Research (PIK), which took part in the work, rapid emissions cuts can still limit the damage, while new science is making it increasingly possible to trace who is responsible for climate harm.

The climate report is a joint initiative of Future Earth, The Earth League and the World Climate Research Programme. Each year it distills the most important advances in climate research from the past 18 months into a short list for policymakers ahead of the UN climate negotiations. A full overview of the climate report is published by Future Earth, and PIK's summary is in its press release.

Some damage is locked in, but the scale is still a choice

The ocean keeps absorbing record amounts of heat, locking in further warming for years to come, the report says. Melting glaciers and ice sheets are accelerating sea-level rise, and some of that rise is now irreversible on human timescales. At the same time freshwater is disappearing fast across continents, as climate change combines with growing human water use to threaten water security, ecosystems and food production.

Wendy Broadgate, Global Hub Director at Future Earth and a member of the report's editorial board, said in a statement that the ocean had acted as a "shock absorber" for the planet's heat. Because heat takes decades to reach the ocean depths, she said, today's emissions "lock in further warming and sea level rise", and deep, rapid emissions cuts are the only way to limit the risks.

Pushing past 1.5°C of warming carries rapidly rising risks of irreversible harm to oceans, glaciers and permafrost, with consequences for livelihoods and economies that stretch decades into the future. The higher temperatures overshoot that limit, and the longer they stay there, the greater the risk becomes. Cooling back below the threshold later would not simply undo the damage done during the overshoot.

PIK director Johan Rockström, co-chair of The Earth League and a member of the report's editorial board, said the evidence was unequivocal that the 1.5-degree threshold is crossed at great risk. Beyond it, he said, "cascading and potentially irreversible climate impacts" grow more severe with every additional tenth of a degree.

The economic costs are much bigger than earlier estimates

One of the report's most striking findings is that the true social cost of carbon — the economic damage caused by each extra ton of CO2 — has been severely underestimated. Newer, more realistic climate models project average economic losses by 2100 under high-warming scenarios of around 40% of GDP, compared with around 11% in earlier estimates, and can yield social cost of carbon estimates up to four times higher than before.

The report also shows how the extra heat people experience in cities changes the math. Accounting for urban heat raises the estimated economic damage from burning a single litre of petrol from USD 0.44 to USD 1.14, according to figures highlighted by the Stockholm Resilience Centre. Every extra ton of emissions, the authors argue, carries more risk and a bigger price tag than policymakers have been assuming.

Scientists can now link specific emitters to specific damage

Advances in attribution science now let researchers connect the emissions of specific countries, companies and sectors to specific climate impacts. The report says this growing evidence base is already being used to strengthen climate litigation, inform loss-and-damage negotiations and sharpen debates over responsibility and finance.

The report also flags intentional climate obstruction as a major barrier to action. Efforts to delay action have moved away from outright science denial toward subtler tactics, including greenwashing, misleading solutions and digital disinformation spread at scale, the authors say. Geopolitical instability adds another complication. It can speed up the clean-energy transition in some countries while deepening fossil-fuel reliance in others, with growing risks of an unequal global shift.

Not all the findings are warnings. Transforming food systems — especially through more plant-rich diets supported by changes across production and supply chains — can deliver major benefits for climate, biodiversity and health, though the authors say the shift must be handled carefully and fairly. International cooperation through so-called "climate clubs", which link climate action to trade measures, could encourage stronger decarbonization, but their design matters: the same measures could impose disproportionate costs on developing economies.

Taken together, the authors describe a narrowing window for action that is still open. What is already locked in, what can still be avoided, and where policy can have the greatest effect: those are the questions the report puts in front of negotiators heading into the next round of UN climate talks.

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image_search_query: melting glacier calving ocean scientists measuring sea level rise image_description: A massive glacier front calving ice chunks into dark ocean water while researchers in orange jackets stand on a rocky shoreline measuring the retreating ice face.