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Many parts of the Earth system can reach a point beyond which change in response to pressure can become self-sustaining, resulting in an often irreversible and abrupt shift to a very different state - what we refer to as a ‘tipping point’. In this chapter we briefly summarise each proposed tipping system covered by the last Global Tipping Points Report, and reassess each based on relevant new scientific research published since the last report.
In the cryosphere - Earth’s frozen reaches - we (the Global Tipping Points community) maintain high confidence in ice sheet tipping points, two of which have been at risk since around 1°C of warming, with potentially substantial consequences for future sea level rise. We also maintain medium confidence in local to regional tipping in permafrost and glaciers, with implications for amplified emissions and regional deglaciation. While Arctic summer sea ice decline is unlikely to reach a tipping point, we cannot rule out tipping for it in the winter, or around Antarctica, where sea ice has recently dropped for the first time.
In the biosphere - the living world - we are more confident in the potential for tipping in the Amazon at various scales, and note that combined with ongoing deforestation as little as 1.5°C of warming could trigger widespread dieback. Both the Amazon and coral reefs have suffered during the 2024-25 El Niño event, seeing the worst coral bleaching event on record and signs of die-off in many regions. We also have higher confidence in localised mangrove tipping, and now include peat bogs and river deltas as potential freshwater tipping systems.
In the circulations of the ocean and atmosphere, recent research strengthens the case for North Atlantic convection being capable of tipping, potentially at current warming levels, but large uncertainties remain on if and when they may tip in practice. Convection around Antarctica may also be weakening towards a tipping point, driven by warming and meltwater, but we are not sure how this in turn interacts with ice melt. We now include the East Asian summer monsoon as a potential tipping system, but remain confident that despite changes in response to warming the northern polar ‘jet stream’ as well as the El Niño Southern Oscillation (ENSO) and large-scale tropical circulations are unlikely to have a tipping point.
Tipping points do not exist in isolation - they interact in ways that can change the likelihood of their tipping. We have extended our previous analysis to cover more than twenty climate tipping system interactions, adding in for example interactions with subglacial basins in East Antarctica or interactions with the permafrost. Our newest science updates maintain the finding that the majority are destabilising. For example, a vicious cycle may form where permafrost thaw releases greenhouse gases, driving further warming and more Arctic sea ice retreat, which by making the Arctic darker amplifies warming, amplifying inland permafrost degradation, and so on. The AMOC emerges as a key global mediator of tipping point interactions, featuring in nearly half of all assessed tipping point interactions, including a few that may potentially have a stabilising effect, such as AMOC collapse’s impact on the southern Amazon rainforest, and West Antarctic Ice Sheet impact on the AMOC.
