Earth’s natural defences are losing strength as temperatures rise, major new report warns.
The planet’s natural carbon sinks – the ocean, forests and soils – are reaching their limits, absorbing less carbon than expected and risking a major setback to global climate targets, according to a major new report launched today ahead of COP30.
The 10 New Insights in Climate Science 2025 report, authored by more than 70 scientists from 21 countries, reveals that decades of climate change have weakened the capacity of land and ocean systems to absorb emissions. The findings suggest that reliance on nature alone to offset carbon pollution is no longer sufficient and that large-scale, responsible deployment of novel carbon-removal technologies must accompany rapid emission cuts.
The report warns that as the world warms, even the ocean – a vital buffer against rising temperatures – is soaking up less carbon dioxide. Meanwhile increasingly frequent marine heatwaves are devastating ecosystems and threatening coastal livelihoods.
“We’ve long relied on forests and soils to quietly clean up our carbon mess, but their capacity is faltering,” said Professor Sabine Fuss, department leader at the Potsdam Institute for Climate Impact Research and member of the report’s editorial board. “That means we may be underestimating the current emissions gap as well as the pace of future warming.”
“The evidence is now clear that rising temperatures and intensifying marine heatwaves are weakening the ocean’s ability to store carbon.”
Dr Katie Smith, Postdoctoral Research Assistant, Marine Biological Association.
MBA’s contribution highlights marine impacts
Among the report’s contributing authors is Dr Katie Smith of the Marine Biological Association (MBA), who co-authored Insight 2, on accelerating sea surface temperatures and intensifying marine heatwaves.
“The ocean has been our greatest ally in buffering the impacts of climate change; the evidence is now clear that rising temperatures and intensifying marine heatwaves are weakening the ocean’s ability to store carbon,” Dr Smith explains. “These changes are already affecting marine ecosystems, fisheries, and the communities that depend on them.”
Dr Smith noted that marine heatwaves are now occurring more often and lasting longer: “We’re seeing water temperatures three to five degrees above what we’d expect for the time of year, sometimes for months at a time. These events destroy kelp forests, bleach coral reefs, and trigger cascading effects that ripple through entire ecosystems.”
Pre-warned is pre-armed
Despite the challenges, Dr Smith remains focused on solutions: “For the first time, we can forecast when and where marine heatwaves are likely to occur. That gives us a window to act – to study them in real time, advise fisheries, and prepare coastal industries before the damage is done.”
The MBA is distinctly positioned to tackle these challenges and find solutions.
“Working at the MBA gives us an incredible platform,” she explains. “With long-term data from the Continuous Plankton Recorder survey and experimental facilities right on Plymouth Sound, we’re uniquely placed to study how marine life responds to rapid warming and to provide the evidence policymakers need. The MBA’s long-term records and experimental facilities mean we can turn global headlines into local evidence – this is essential if we’re to move from observing change to managing it.”
A call for science-driven action ahead of COP30
Produced jointly by Future Earth, The Earth League, and the World Climate Research Programme, the 10 New Insights report synthesises the most critical climate-science advances from the past 18 months. It highlights how the record warmth of 2023 and 2024 is straining global water resources, spreading vector-borne diseases like dengue, and reducing labour productivity through heat stress.
“The climate negotiations must be guided by science, and the 10 New Insights provide the best summary of the latest updates in climate research,” said Johan Rockström, co-chair of The Earth League. “COP30 must be the COP of implementation; we can no longer afford new promises without delivery.”
Key findings from the report
- Record warming 2023/24: Evidence points to a possible acceleration of global warming.
- Accelerated ocean warming: Marine heatwaves are damaging ecosystems and intensifying extreme-weather risks.
- Strain on land carbon sinks: Forests and soils are showing signs of stress.
- Climate–biodiversity feedback: Biodiversity loss and climate change reinforce each other.
- Declining groundwater levels: Climate change accelerates water depletion.
- Climate-driven dengue outbreaks: Warming expands the mosquito’s habitat.
- Impacts on labour productivity: Heat stress threatens livelihoods and economic stability.
- Scaling carbon-dioxide removal (CDR): Needed, but must focus on hard-to-abate emissions.
- Carbon-market integrity challenges: Stronger benchmarks and transparency are essential.
- Effective policy mixes: Combining measures achieves deeper, lasting emission cuts.
About the 10 New Insights in Climate Science
The10 New Insights in Climate Science is an annual publication that distils advances in climate research into clear, policy-relevant findings. It is a joint initiative of Future Earth, The Earth League, and the World Climate Research Programme (WCRP), supported by a global network of scientists and institutions.
