EGU25-3604, updated on 14 Mar 2025
https://doi.org/10.5194/egusphere-egu25-3604
EGU General Assembly 2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
Oral | Thursday, 01 May, 08:30–08:40 (CEST)
 
Room 1.34
The Atlantic overturning circulation (AMOC) ceases in many CMIP6 projections after 2100
Stefan Rahmstorf1,2, Sybren Drijfhout3,4,5, Joran Angevaare3, and Jennifer Mecking6
Stefan Rahmstorf et al.
  • 1Potsdam Institute for Climate Impact Research, Germany
  • 2University of Potsdam, Institute of Physics and Astronomy, Germany
  • 3Royal Netherlands Meteorological Institute, de Bilt, Netherlands
  • 4University of Utrecht, Netherlands
  • 5Ocean and Earth Science, National Oceanography Centre Southampton, University of Southampton, Southampton, SO14 3ZH, UK
  • 6National Oceanography Centre, Southampton, UK

New global warming projections in CMIP6 contain extensions beyond year 2100 up to 2300/2500. The Atlantic Meridional Overturning Circulation (AMOC) in these runs essentially ceases in all models forced by a high emissions (SSP585) scenario and sometimes also in models forced by intermediate (SSP245) or low (SSP126) scenarios. These extremely weak overturning states merely maintain a wind-driven shallow overturning at depths less than 200 m. Northward mass transport below this maximum is either completely absent or less than 2 Sverdrup. In all cases, this AMOC cessation is preceded by a mid-21st century collapse of deep convection in Labrador, Irminger and Nordic Seas, which likely represents the tipping point triggering the terminal AMOC decline.

How to cite: Rahmstorf, S., Drijfhout, S., Angevaare, J., and Mecking, J.: The Atlantic overturning circulation (AMOC) ceases in many CMIP6 projections after 2100, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-3604, https://doi.org/10.5194/egusphere-egu25-3604, 2025.