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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
Stefan Rahmstorf, Professor of Physics os the Ocean at the University of Potsdam since 2000, presents a colloquium on the risks associated with the destabilization of the Atlantic Meridional Overturning Circulation (AMOC) and its potential consequences for the global climate.
Recent simulations using the Community Earth System Model (CESM) indicate that a tipping event of the Atlantic Meridional Overturning Circulation (AMOC) would cause Europe to cool by several degrees. This AMOC tipping event was found under constant pre-industrial greenhouse gas forcing, while global warming likely limits this AMOC-induced cooling response. Here, we quantify the European temperature responses under different AMOC regimes and climate change scenarios. A strongly reduced AMOC state and intermediate global warming (C, Representative Concentration Pathway 4.5) has a profound cooling effect on Northwestern Europe with more intense cold extremes. The largest temperature responses are found during the winter months and these responses are strongly influenced by the North Atlantic sea-ice extent. Enhanced North Atlantic storm track activity under an AMOC collapse results in substantially larger day-to-day temperature fluctuations. We conclude that the (far) future European temperatures are dependent o
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.
Thousands of Greenland's crystal-clear blue lakes have turned a murky brown thanks to global warming — and the worst part is that they've started emitting carbon dioxide. Record heat and rain in 2022 pushed the lakes of West Greenland past a tipping point, so rather than absorbing carbon dioxide (CO₂), they began to emit it into the atmosphere, according to a new study.
The year 2024 wasn’t just another chapter in the unfolding climate saga; it felt like the plot twist no one wanted to believe. For decades, climate scientists warned of ifs — if we pass this tipping…
De metafoor van het 'tipping point' of 'kantelpunt' is contraproductief in de context van de klimaatopwarming, argumenteert een groep wetenschappers in het vakblad Nature. Het concept kan mensen in verwarring brengen en actie in de weg staan, denken de onderzoekers.
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.
Oceanographer Stefan Rahmstorf explains why Amoc breakdown could be catastrophic for both humans and marine life
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.
Under current emission trajectories, temporarily overshooting the Paris global warming limit of 1.5 °C is a distinct possibility. Permanently exceeding this limit would substantially increase the probability of triggering climate tipping elements. Here, we investigate the tipping risks associated with several policy-relevant future emission scenarios, using a stylised Earth system model of four interconnected climate tipping elements.
Nous voici arrivés à la moitié de la décennie 2020, celle qui est censée être décisive pour l'action contre le changement climatique. Mais où en sommes-nous exactement ? Johan Rockström est un universitaire spécialisé dans l'impact climatique. Il nous présente l'évaluation scientifique la plus récente sur l'état de notre planète et explique ce que nous devons faire pour préserver la résilience de la Terre face à la pression humaine.
Small increase in temperature of intruding water could lead to very big increase in loss of ice, scientists say
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.
RealClimate: A new paper was published in Science Advances today. Its title says what it is about: "Physics-based early warning signal shows that AMOC is on tipping course." The study follows one by Danish colleagues which made headlines last July, likewise looking for early warning signals for approaching an AMOC tipping point (we discussed it here),
Scientists now have a better understanding of the risks ahead and a new early warning signal to watch for.
Collapse in system of currents that helps regulate global climate would be at such speed that adaptation would be impossible
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.
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.”
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.
filtre:
tipping
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
Stefan Rahmstorf, Professor of Physics os the Ocean at the University of Potsdam since 2000, presents a colloquium on the risks associated with the destabilization of the Atlantic Meridional Overturning Circulation (AMOC) and its potential consequences for the global climate.
Recent simulations using the Community Earth System Model (CESM) indicate that a tipping event of the Atlantic Meridional Overturning Circulation (AMOC) would cause Europe to cool by several degrees. This AMOC tipping event was found under constant pre-industrial greenhouse gas forcing, while global warming likely limits this AMOC-induced cooling response. Here, we quantify the European temperature responses under different AMOC regimes and climate change scenarios. A strongly reduced AMOC state and intermediate global warming (C, Representative Concentration Pathway 4.5) has a profound cooling effect on Northwestern Europe with more intense cold extremes. The largest temperature responses are found during the winter months and these responses are strongly influenced by the North Atlantic sea-ice extent. Enhanced North Atlantic storm track activity under an AMOC collapse results in substantially larger day-to-day temperature fluctuations. We conclude that the (far) future European temperatures are dependent o
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.
Thousands of Greenland's crystal-clear blue lakes have turned a murky brown thanks to global warming — and the worst part is that they've started emitting carbon dioxide. Record heat and rain in 2022 pushed the lakes of West Greenland past a tipping point, so rather than absorbing carbon dioxide (CO₂), they began to emit it into the atmosphere, according to a new study.
The year 2024 wasn’t just another chapter in the unfolding climate saga; it felt like the plot twist no one wanted to believe. For decades, climate scientists warned of ifs — if we pass this tipping…
De metafoor van het 'tipping point' of 'kantelpunt' is contraproductief in de context van de klimaatopwarming, argumenteert een groep wetenschappers in het vakblad Nature. Het concept kan mensen in verwarring brengen en actie in de weg staan, denken de onderzoekers.
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.
Oceanographer Stefan Rahmstorf explains why Amoc breakdown could be catastrophic for both humans and marine life
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.
Under current emission trajectories, temporarily overshooting the Paris global warming limit of 1.5 °C is a distinct possibility. Permanently exceeding this limit would substantially increase the probability of triggering climate tipping elements. Here, we investigate the tipping risks associated with several policy-relevant future emission scenarios, using a stylised Earth system model of four interconnected climate tipping elements.
Nous voici arrivés à la moitié de la décennie 2020, celle qui est censée être décisive pour l'action contre le changement climatique. Mais où en sommes-nous exactement ? Johan Rockström est un universitaire spécialisé dans l'impact climatique. Il nous présente l'évaluation scientifique la plus récente sur l'état de notre planète et explique ce que nous devons faire pour préserver la résilience de la Terre face à la pression humaine.