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Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say

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.

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

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.

Collapse in system of currents that helps regulate global climate would be at such speed that adaptation would be impossible

Scientists now have a better understanding of the risks ahead and a new early warning signal to watch for.

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

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).

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.

Extreme milieufenomenen zoals bosbranden en droogtes zetten ecosystemen zodanig onder druk dat ze steeds moeilijker terug evenwicht vinden. Dat leidt dan tot een zogeheten tipping point voor ecologisch verval. En die kantelpunten komen steeds sneller, zegt een nieuwe studie in Nature.

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

By replacing thousands of equations with just one, ecology modelers can more accurately assess how close fragile environments are to a disastrous “tipping point.”

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.

Analysis shows significant risk of cascading events even at 2C of heating, with severe long-term effects. The new research examined the interactions between ice sheets in West Antarctica, Greenland, the warm Atlantic Gulf Stream and the Amazon rainforest. The scientists carried out 3m computer simulations and found domino effects in a third of them, even when temperature rises were below 2C, the upper limit of the Paris agreement.

Governments and businesses failing to change fast enough, says United in Science report, as weather gets increasingly extreme. Despite intensifying warnings in recent years, governments and businesses have not been changing fast enough, according to the United in Science report published on Tuesday. The consequences are already being seen in increasingly extreme weather around the world, and we are in danger of provoking “tipping points” in the climate system that will mean more rapid and in some cases irreversible shifts.

Le rythme actuel de réchauffement pourrait déclencher plusieurs « points de bascule » planétaires : des changements abrupts et irréversibles du système climatique. Les chercheurs Aurélien Boutaud et Natacha Gondran nous expliquent pourquoi.

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

As Nobel laureate Solow said to Congress when criticizingeconomicmodelsforfailingtoanticipatethe“GreatReces-sion,” “Every proposition has to pass a smell test: Does itreally make sense?” (2). The methods and conclusions inDietzetal.(1)donotmakesense. ...

Anthropogenic activities are increasingly affecting ecosystems across the globe. Meanwhile, empirical and theoretical evidence suggest that natural systems can exhibit abrupt collapses in response to incremental increases in the stressors, sometimes with dramatic ecological and economic consequences. These catastrophic shifts are faster and larger than expected from the changes in the stressors and happen once a tipping point is crossed.

Climate tipping points in the Antarctica, the Arctic and the Amazon are at risk of being reached before or at the current level of global warming of 1.2 degrees Celsius, requiring a “major rethink” of global climate goals and the action necessary to achieve them, according to a recent report.

More than three-quarters of the world's largest rainforest has become less resilient to drought since the early 2000s, with areas near humans and with lower rainfall being the worst hit

Emerging ice-sheet modeling suggests once initiated, retreat of the Antarctic Ice Sheet (AIS) can continue for centuries. Unfortunately, the short observational record cannot resolve the tipping points, rate of change, and timescale of responses. Iceberg-rafted debris data from Iceberg Alley identify eight retreat phases after the Last Glacial Maximum that each destabilized the AIS within a decade, contributing to global sea-level rise for centuries to a millennium, which subsequently re-stabilized equally rapidly.

Five times in the last 500m years, more than three-fourths of marine animal species perished in mass extinctions. Each of these events is associated with a major disruption of Earth’s carbon cycle. How such catastrophes occur remains mysterious. But recent research increasingly points to the possibility that the Earth system – that is, life and the environment – may experience a cascade of disruptions when stressed beyond a tipping point.

The growing threat of abrupt and irreversible climate changes must compel political and economic action on emissions.

If there’s one thing we know about climate breakdown, it’s that it will not be linear, smooth or gradual. Just as one continental plate might push beneath another in sudden fits and starts, causing periodic earthquakes and tsunamis, our atmospheric systems will absorb the stress for a while, then suddenly shift. Yet, everywhere, the programmes designed to avert it are linear, smooth and gradual.

Scientists have uncovered a fascinating new insight into what caused one of the most rapid and dramatic instances of climate change in the history of the Earth.

Depuis 30 ans, la compréhension du climat terrestre dans sa globalité s’est donc terriblement améliorée, permettant le développement de nouveaux concepts. L’un d’entre eux suscite beaucoup d’intérêt auprès de la communauté scientifique : c’est celui des points de basculement (tipping point).

Clarity on Climate Tipping Points and Feedbacks

The IPCC report sets out the world’s current knowledge of the impacts of 1.5C of warming and clearly shows the dangers of breaching such a limit. However, many scientists are increasingly worried about factors about which we know much less. These “known unknowns” of climate change are tipping points, or feedback mechanisms within the climate system – thresholds that, if passed, could send the Earth into a spiral of runaway climate change.