Parts of the Earth’s climate system can change abruptly once 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.
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 Proceedings of the National Academy of Sciences, colleagues and I examined 20,736 scientific publications on 14 climate tipping elements published between 2000 and 2025. We wanted to know where scientific attention has accumulated, and whether the systems with relatively low estimated warming thresholds tend to receive more of it.
An uneven research landscape
The Greenland Ice Sheet dominates the studies we analysed. It appeared in 4,141 publications — 20 per cent 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 per cent. The North Atlantic subpolar gyre, a system of ocean circulation south of Greenland, accounted for 649 papers, or 3.1 per cent. Other potential 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.
The more revealing comparison is with estimated warming thresholds.
In our study, we compared research attention with published estimates of the level of global warming at which each system might tip. Abrupt boreal permafrost thaw, for example, has a best-estimate threshold of about 1.5°C above pre-industrial temperatures. The estimate for the North Atlantic subpolar gyre is around 1.8°C. Greenland’s is also around 1.5°C.
Yet we found no systematic tendency for tipping elements with lower estimated thresholds (that is, elements presumed to tip earlier) to attract more scientific attention. Some receive thousands of studies; others, with similarly low estimated thresholds, receive hundreds or fewer.
This result needs some care.
A warming threshold is not a timer counting down to a known date. Estimates come with substantial uncertainty, and scientists continue to debate the behaviour of several potential tipping elements. Nor does the number of publications tell us how strong the evidence for a particular tipping point is.
Our analysis measures scientific attention. It does not measure scientific certainty, the quality of individual studies or the importance of one tipping element relative to another.
There are also overlaps between research areas. The North Atlantic Subpolar Gyre, for instance, is closely connected with the Atlantic Meridional Overturning Circulation, or Amoc. Some relevant research may therefore appear in the much larger Amoc studies without treating the gyre as a separate tipping element.
We also looked beyond which systems scientists study to what they study about them.
What makes a tipping point unusual is not simply that a system changes. The change may happen abruptly. It may reinforce itself. The system may settle into a different state, or fail to return to its previous one even if the original pressure is reduced.
We therefore looked for studies that gave explicit attention to these kinds of tipping dynamics — abrupt change, self-perpetuation, persistence and irreversibility.
Only 8.1 per cent of the publications we analysed 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.
Filling the gaps
None of this suggests that scientists studying Greenland or the Amoc should redirect their research elsewhere. There are good reasons why particular fields develop large research communities, with scientists able to monitor the real world and model it with computers.
But research priorities are also shaped collectively — by funding programmes, scientific institutions and decisions about where new monitoring and modelling capacity should be built.
For tipping elements with relatively low estimated warming thresholds but comparatively little research, additional studies may help establish what is known, what remains uncertain and which uncertainties are most consequential. The same applies to the processes that make tipping different from gradual environmental change: whether transitions can become abrupt, self-perpetuating or irreversible.
As global warming continues, decision-makers should ask a straightforward question: which potentially consequential climate risks remain difficult to assess because comparatively little scientific attention has reached them?
Finding those gaps before the climate system tests them for us would be a useful place to start.
Asaf Tzachor, Research Affiliate, Centre for the Study of Existential Risks, University of Cambridge
This article is republished from The Conversation under a Creative Commons license. Read the original article.