No collapswashing

Economic assumptions about risks of the climate crisis are no longer relevant, says the communications expert Genevieve Guenther

The world has been too optimistic about the risk to humanity and planet – but devastation can still be avoided, says Timothy Lenton

Despite working on polar science for the British Antarctic Survey for 20 years, Louise Sime finds the magnitude of potential sea-level rise hard to comprehend

We investigate the probabilities of triggering climate tipping points under five Shared Socioeconomic Pathways (SSPs) and how they are altered by including the additional carbon emissions that could arise from tipping points within the Earth's carbon cycle. The crossing of a climate tipping point at a threshold level of global mean surface temperature (threshold temperature) would commit the affected subsystem of the Earth to abrupt and largely irreversible changes with negative impacts on human well-being. However, it remains unclear which tipping points would be triggered under the different SSPs due to uncertainties in the climate sensitivity to anthropogenic greenhouse gas emissions, the threshold temperatures and timescales of climate tipping points, and the response of tipping points within the Earth's carbon cycle to global warming. We include those uncertainties in our analysis to derive probabilities of triggering for 16 previously identified climate tipping points within the Earth system.

Tipping elements within the Earth system are increasingly well understood. Scientists have identified more than 25 parts of the Earth’s climate system that are likely to have “tipping points” – thresholds where a small additional change in global warming will cause them to irreversibly shift into a new state. The “tipping” of these systems – which include the Atlantic Meridional Overturning Circulation (AMOC), the Amazon rainforest and the Greenland ice sheet – would have profound consequences for both the biosphere and people. More recent research suggests that triggering one tipping element could cause subsequent changes in other tipping elements, potentially leading to a “tipping cascade”. For example, a collapsed AMOC could lead to dieback of the Amazon rainforest and hasten the melt of the Greenland ice sheet.

Lenton, the founding director of the Global Systems Institute at the University of Exeter, was the lead author of the 2008 paper that formally introduced the idea of tipping points in the Earth’s climate system.

Franchir les points de bascule écologiques aurait un coût économique gigantesque, selon plusieurs études scientifiques récentes. Des données qui rappellent l’urgence d’atténuer la crise écologique avant d’être face à des conséquences irréversibles en cascade.

We're nearly halfway through the 2020s, dubbed the most decisive decade for action on climate change. Where exactly do things stand? Climate impact scholar Johan Rockström offers the most up-to-date scientific assessment of the state of the planet and explains what must be done to preserve Earth's resilience to human pressure.

For many of us the climate crisis mainly calls to mind rising global temperatures, but the crisis goes far beyond this – we are at risk of pushing our planet across climate ‘tipping points,’ critical thresholds where small changes can lead to abrupt and irreversible shifts in the Earth’s climate system. One major element in climate tipping is a huge system of ocean currents, the Atlantic Meridional Overturning Circulation (AMOC), which is responsible for Europe's relatively mild climate. Past climate patterns show that these currents can switch abruptly between today’s vigorous flow and a much weaker flow state. A future shutdown would have potentially devastating consequences in Europe and around the world.

An international team of scientists has warned against relying on nature providing straightforward 'early warning' indicators of a climate disaster, as new mathematical modeling shows new fascinating aspects of the complexity of the dynamics of climate. It suggests that the climate system could be more unpredictable than previously thought.

Cruciale kantelpunten in het klimaatsysteem van de aarde komen in sneltempo dichterbij. Dat blijkt uit het grootste onderzoek ooit naar “tipping points”. Meer dan tweehonderd wetenschappers werkten mee aan een tekst met waarschuwingen en aanbevelingen, die is gepresenteerd op de klimaattop in Dubai (COP28).

Humanity faces ‘devastating domino effects’ including mass displacement and financial ruin as planet warms

Take part in the new scientific discussion about looming abrupt changes in the Earth system. This new webinar series invites scientists interested in tipping elements and the broader public to attend.

Amazon rainforest and other ecosystems could collapse ‘very soon’, researchers warn

Vast releases of gas, along with future ‘methane bombs’, represent huge threat – but curbing emissions would rapidly reduce global heating

The Global Tipping Points Report was launched at COP28 on 6 December 2023. The report is an authoritative assessment of the risks and opportunities of both negative and positive tipping points in the Earth system and society. Global Tipping Points is led by Professor Tim Lenton from the University of Exeter’s Global Systems Institute with the support of more than 200 researchers from over 90 organisations in 26 countries.

Three “super-tipping points” for climate action could trigger a cascade of decarbonisation across the global economy, according to a report. Relatively small policy interventions on electric cars, plant-based alternatives to meat and green fertilisers would lead to unstoppable growth in those sectors, the experts said. But the boost this would give to battery and hydrogen production would mean crucial knock-on benefits for other sectors including energy storage and aviation.

A recent paper suggested damaging climate tipping points could be closer than first thought.

Giant ice sheets, ocean currents and permafrost regions may already have passed point of irreversible change

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