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On why collapse could be much closer than predicted: what happens when the Atlantic Ocean’s heart stops beating?
The Atlantic Meridional Overturning Circulation is the main driver of northward heat transport in the Atlantic Ocean today, setting global climate patterns. Whether global warming has affected the strength of this overturning circulation over the past century is still debated: observational studies suggest that there has been persistent weakening since the mid-twentieth century, whereas climate models systematically simulate a stable circulation. Here, using Earth system and eddy-permitting coupled ocean–sea-ice models, we show that a freshening of the subarctic Atlantic Ocean and weakening of the overturning circulation increase the temperature and salinity of the South Atlantic on a decadal timescale through the propagation of Kelvin and Rossby waves. We also show that accounting for upper-end meltwater input in historical simulations significantly improves the data–model agreement on past changes in the Atlantic Meridional Overturning Circulation, yielding a slowdown of 0.46 sverdrups per decade since 1950
The idea that the AMOC is headed to collapse is very controversial, but it is clearly weakening. If the circulation did collapse, the consequences on both sides of the Atlantic Ocean would be immense—including large changes in temperature and a spike in weather-related disasters.
The Atlantic Ocean's most vital ocean current is showing troubling signs of reaching a disastrous tipping point. Oceanographer Stefan Rahmstorf tells Live Science what the impacts could be.
The network of Atlantic ocean currents keeping the Earth's climate stable are far closer to collapse than first estimated, scientists warn.
AMOC collapse would bring severe global climate repercussions, with Europe bearing the brunt of the consequences.
Oceanographer Stefan Rahmstorf explains why Amoc breakdown could be catastrophic for both humans and marine life
Several studies in recent years have suggested the crucial system — the Atlantic Meridional Overturning Circulation, or AMOC — could be on course for collapse, weakened by warmer ocean temperatures and disrupted saltiness caused by human-induced climate change. But the new research, which is being peer-reviewed and hasn’t yet been published in a journal, uses a state-of-the-art model to estimate when it could collapse, suggesting a shutdown could happen between 2037 and 2064.
There is increasing concern that the Atlantic Meridional Overturning Circulation (AMOC) may collapse this century with a disrupting societal impact on large parts of the world. Preliminary estimates of the probability of such an AMOC collapse have so far been based on conceptual models and statistical analyses of proxy data. Here, we provide observationally based estimates of such probabilities from reanalysis data. We first identify optimal observation regions of an AMOC collapse from a recent global climate model simulation. Salinity data near the southern boundary of the Atlantic turn out to be optimal to provide estimates of the time of the AMOC collapse in this model. Based on the reanalysis products, we next determine probability density functions of the AMOC collapse time. The collapse time is estimated between 2037-2064 (10-90% CI) with a mean of 2050 and the probability of an AMOC collapse before the year 2050 is estimated to be 59±17%.
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
Disruption of the Atlantic Meridional Overturning Current could freeze Europe, scorch the tropics and increase sea level rise in the North Atlantic. The tipping point may be closer than predicted in the IPCC’s latest assessment.
Wereldnieuws was het de laatste weken. ‘De Golfstroom kan stilvallen in 2025’, kopten kranten naar aanleiding van een recent verschenen paper. In feite ging de publicatie niet over de Golfstroom, maar over de Atlantic Meridional Overturning Circulation, kortweg AMOC. En bij de genoemde termijn vallen ook vraagtekens te plaatsen. Wat zegt de wetenschap over al die amok rond de AMOC? ‘Of het nu in 2025 is of in 2100, we willen niet dat dit gebeurt.’
The Atlantic meridional overturning circulation (AMOC) is a major tipping element in the climate system and a future collapse would have severe impacts on the climate in the North Atlantic region. In recent years weakening in circulation has been reported, but assessments by the Intergovernmental Panel on Climate Change (IPCC), based on the Climate Model Intercomparison Project (CMIP) model simulations suggest that a full collapse is unlikely within the 21st century. Tipping to an undesired state in the climate is, however, a growing concern with increasing greenhouse gas concentrations. Predictions based on observations rely on detecting early-warning signals, primarily an increase in variance (loss of resilience) and increased autocorrelation (critical slowing down), which have recently been reported for the AMOC. Here we provide statistical significance and data-driven estimators for the time of tipping. We estimate a collapse of the AMOC to occur around mid-century under the current scenario of future emi
RealClimate: For various reasons I'm motivated to provide an update on my current thinking regarding the slowdown and tipping point of the Atlantic Meridional Overturning Circulation (AMOC). I attended a two-day AMOC session at the IUGG Conference the week before last, there's been interesting new papers, and in the light of that I have been changing
It was the hottest June on record, unprecedented North Atlantic warmth, record low Antarctic sea ice
- World Meteorological OrganizationThe world just had the hottest June on record, with unprecedented sea surface temperatures and record low Antarctic sea ice extent, according to a new report.
Marine biologist Bill Montevecchi is ranked in the top two per cent of the world's scientists. While researching the foraging tactics and migratory ecology of seabirds, he has witnessed how the avian flu is killing off seabird colonies in Newfoundland and beyond — and warns something needs to be done.
De nouvelles technologies sont en cours de développement et rendent possible une révolution systémique de la production alimentaire.
Howard Dryden reached out to me to express his dismay at having been misquoted by the Sunday Post, which should have reported a "90% reduction in marine plankton in the Equatorial Atlantic, not the whole Atlantic." "The issue is that the findings are accurate and what is stated in the report are true. We are the first to identify the huge concentration of PCC, and the drop in Plankton. We are working with some academic institutes to prepare a formal peer reviewed report, but this takes time and I was so depressed by the results and the fact that we did not see a single whale or big fish, except for a few flying fish for 20 days at sea. This was the same for all the vessels and anyone now sailing in the equatorial Atlantic," Dryden told Ars. "The results should of course be verified independently, and it should be opened up to proper debate. This may be one of the few chances we have and others to pick up the issues and deal with them. If we fail to act and eliminate PCC pollution, microplastics and for e
Après deux décennies de développement industriel intensif, le géant démographique de la planète souffre d’une pénurie extrêmement inquiétante qui pourrait bien le pousser à menacer ses voisins asiatiques.
Researchers examined the economic cost of the climate crisis and found it would cut about 37% from global GDP this century, more than twice the drop experienced in the Great Depression. For every tonne of carbon dioxide emitted, the global economy would be $3,000 worse off by the end of the century, they estimated.
How Greta Thunberg became the target of a barrage of disinformation and conspiracies.
The Atlantic Ocean's current system, an engine of the Northern Hemsiphere's climate, could be weakening to such an extent that it could soon bring big changes to the world's weather, a scientific study said on Thursday.
The Atlantic Meridional Overturning Circulation (AMOC), a major ocean current system transporting warm surface waters toward the northern Atlantic, has been suggested to exhibit two distinct modes of operation. A collapse from the currently attained strong to the weak mode would have severe impacts on the global climate system and further multi-stable Earth system components. Observations and recently suggested fingerprints of AMOC variability indicate a gradual weakening during the last decades, but estimates of the critical transition point remain uncertain.
On September 14, 1869, 25,000 people marched through New York to celebrate the centennial of the birth of German scientist Alexander von Humboldt.