Blind spots: Unseen climate tipping points demand focus

Parts of the Earth's climate system can change abruptly once global warming pushes them beyond critical thresholds. The Greenland and Antarctic ice sheets, the Amazon rainforest, coral reefs, and major ocean currents are all among the systems containing potential climate tipping points.

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These climate systems are known as tipping elements, and research into them has expanded rapidly. But it has not expanded evenly.

In a new study published in the Proceedings of the National Academy of Sciences, my colleagues and I examined 20,736 scientific publications on 14 climate tipping elements published between 2000 and 2025. We aimed to determine where scientific attention has concentrated and whether systems with relatively low estimated warming thresholds tend to receive greater focus.

The Greenland Ice Sheet dominates the studies we analysed. It appeared in 4,141 publications - 20% of the entire dataset.

By contrast, abrupt thaw of permafrost in boreal forests just below the Arctic appeared in just 139 papers, or 0.7%. The North Atlantic subpolar gyre, a crucial ocean circulation south of Greenland, accounted for 649 papers, or 3.1%. Other vital tipping elements, including Barents Sea winter ice and the East Antarctic subglacial basins, also had comparatively little research.

Unequal publication numbers are not, by themselves, surprising. Some parts of the climate system have been observed for longer, are easier to measure or model, or sit within larger and better-established scientific fields.

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The more revealing comparison is with estimated warming thresholds.

In our analysis, we matched research volume against published estimates of the global warming levels at which each system might tip. Abrupt boreal permafrost thaw, for instance, carries a best-estimate threshold of about 1.5°C above pre-industrial levels. The estimate for the North Atlantic subpolar gyre sits around 1.8°C, while Greenland's threshold is also roughly 1.5°C.

Yet we found no systematic trend showing that tipping elements with lower estimated thresholds -- those presumed to tip sooner -- attract more scientific attention. Some receive thousands of studies, while others with similarly low thresholds receive merely a few hundred or fewer.

This finding requires careful interpretation. A warming threshold is not a countdown timer ticking toward a precise date. These estimates come with substantial uncertainty, and scientists continue to debate the exact behaviour of several potential tipping elements. Furthermore, the sheer volume of publications does not automatically reflect the strength of evidence for a specific tipping point.

.Our analysis measures scientific attention. It does not measure scientific certainty, the quality of individual papers, or the relative importance of one tipping element over another.Overlap between research areas also plays a role. The North Atlantic Subpolar Gyre, for example, connects closely with the broader Atlantic Meridional Overturning Circulation (AMOC). Consequently, relevant data may be embedded within larger AMOC studies without explicitly treating the gyre as a distinct tipping element.

Beyond identifying which systems scientists study, we examined what specific aspects they investigate.

What makes a tipping point distinct is not simply that a system changes. The shift may happen abruptly and reinforce itself. The system may then settle into an entirely different state, failing to return to its original balance even if the driving pressure subsides.

We searched for studies that explicitly addressed these critical dynamics: abrupt change, self-perpetuation, persistence, and irreversibility.

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Only 8.1% of the analysed publications explicitly examined one or more of these risk-relevant characteristics.

The gaps were particularly striking for some individual systems. Across 26 years of research, we identified just 22 peer-reviewed scientific studies examining such dynamics in abrupt boreal permafrost thaw, low-latitude coral reefs and a mere 53 on the North Atlantic Subpolar Gyre.

This does not imply that scientists studying Greenland or the AMOC should abandon their work. Good reasons exist for why large research communities form around specific fields, enabling detailed real-world monitoring and computer modelling.

However, research priorities are also shaped collectively by funding programmes, institutional agendas, and strategic choices regarding where to build new monitoring and modelling capacity.

For tipping elements with low estimated warming thresholds but little dedicated research, expanding investigation would help clarify what is known, what remains uncertain, and which uncertainties pose the greatest risk. As global warming continues, decision-makers must ask which consequential climate risks remain hard to assess simply because too little scientific attention has reached them.