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JD Vance was supposed to be the inconsequential vice-president. But his starring role in Friday’s blowup between Donald Trump and Volodymyr Zelenskyy – where he played a cross between Trump’s bulldog and a tech bro Iago – may mark the moment that the postwar alliance between Europe and the US finally collapsed.

The Atlantic Meridional Overturning Circulation (AMOC), vital for northwards heat transport in the Atlantic Ocean, is projected to weaken owing to global warming1, with significant global climate impacts2. However, the extent of AMOC weakening is uncertain with wide variation a …

EDF a passé une dépréciation pour 900 millions d'euros sur le projet éolien en mer Atlantic Shores, aux États-Unis, auquel participait le groupe français au sein d'une coentreprise avec Shell, a-t-il indiqué vendredi, après l'annonce d'un gel des permis d'exploitation par Donald Trump.

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Global warming is moving faster than the best models can keep a handle on.

Several high-profile research papers have brought renewed attention to the potential collapse of a crucial system of ocean currents known as the Atlantic Meridional Overturning Circulation, or AMOC, as we discussed in part one of this two-part post. Huge uncertainties in both the timing and details of potential impacts of such a collapse remain.

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.