Research overview of AMOC collapse

[Robert Höglund]

I've started a research overview of the risk of an AMOC collapse, its potential consequences and what we know about solutions. Would you like to contribute? Comment and I can give you access.
Link: https://noisy-city-cf3.notion.site/AMOC-Research-overview-14fb562c6d1a805e9654f7542c7d9984

Best regards

Robert Höglund
marginalcarbon.com  

twitter.com/roberthoglund 
marginalcarbon.substack.com
linkedin.com/in/roberthoglund 

[Claudia Wieners]

Dear Robert, 

in case that's of help, I've written a section on ocean circulation tipping and SRM in a recent review (preprint available here; full paper hopefully to be accepted soon). 

https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1753/ 

some observations: 

- there is considerable disagreement between models and between researchers on whether AMOC could tip and at what thresholds, on how many observations of which variables at which locations you need to reliably detect past or future weakening, and so on. You have everything from people who claim that tipping seems imminent (Ditlevsen and Ditlevsen; Boers) to people who explain why there methods are flawed and are way more doubtful. 

-> in my view, even a significant probability of AMOC collapse is a very serious risk due to its high potential for disruption; so we'd better take this very seriously even if it's uncertain if AMOC can indeed tip (soon-ish). 

- in existing modelling studies, SRM (most studied are solar dimming and SAI, but MCB also was modelled) SRM generally helps against AMOC weakening, which could mean it also would reduce the chance of tipping. Update wr.t. preprint:  in the CESM model actually SAI and high CO2 had better AMOC results than no SAI and low CO2 (see https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023GL106132 fig. 3)

- in my view, given that we don't know whether we could detect AMOC tipping in time, it would be a very dangerous strategy to use SRM as "just a backup plan in case things go wrong" - we don't know in time! 

about your list: 

- nice start but it would help if you could insert references, because different sources have different views, so it's good to be able to trace back opinions. 

- note that an important  driver of AMOC weakening is also just the direct surface warming, see the study by Gregory: https://gmd.copernicus.org/articles/9/3993/2016/ ... this may be more important than the meltwater or rainfall changes! 

I hope this helps you a bit.

Best

Claudia 

Op ma 9 dec 2024 om 17:27 schreef Robert Höglund <robert.d...@gmail.com>:

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