On our way to 2100, the continued AMOC weakening leads to less and less CO2 uptake. (Which increases social cost of carbon, SCC)
https://www.pnas.org/doi/10.1073/pnas.2419543122
"Weakening AMOC reduces ocean carbon uptake and increases the social cost of carbon" by Schaumann et al 2025.
They combine a geochemical model with a freshwater hosing model and then watch how many CO2 molecules manage to sink to the ocean floor in which warming scenario.
German #scicomm summary:
https://nachrichten.idw-online.de/2025/02/25/schwaechere-meeresstroemung-koennte-billionen-kosten
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Hm. Is that it for the hope for 0 additional warming soon after emissions have stopped. Because that hope is based on how the oceans are assumed to keep removing CO2 from the atmo for a while after zero emissions is achieved.
The slowing #AMOC at its Northernmost branch used to do the heavy lifting in carbon removal via the forklift of temperature and salinity, that's how I read the paper.
Come to think of it, the wind "around" Antarctica is picking up speed due to #climatechange. This wind pulls up water from the deep Southern Ocean and is thus also part of the AMOC, a part projected to speed up, not slow down. Yay.
But.
Pulling up deep water faster also pulls up the old carbon faster which was transported there by the AMOC.
So...uhm, does this increased wind-driven carbon upwelling intensify the effect of the ever-reduced carbon removal by the slowing AMOC?
I bet, this would be visible in #paleoclimate data around the Younger Dryas. Eg, pairing the Greenland annual temperature time series and annual Antarctic CO2 record.
If correct then I'd expect: just before the AMOC collapse, when Greenland still heats up, CO2 growth should increase. And when AMOC slows down, when Greenland starts cooling, the annual growth in CO2 should further intensify.
Unless... hm. The re-cooling also buries a lot of soil and plants under new ice in Scandinavia and Canada. Could be, this process balances the otherwise expected growth increase.Hm.
Going to look at it tomorrow. Am again completely in awe that we do have annually resolved Greenland temperature and Antarctic CO2 levels all the way back to the previous interglacial!!
Between the last glacial maximum & today, humans were exposed to severely rising sea levels 
& recurrent phases of strong abrupt cooling events.
#MPIM researchers have uncovered the origin of these strong temperature fluctuations over the past 20,000 years using a novel coupled climate-ice sheet model. They found that #iceberg armadas 
Invidious: 
Eine 
