EGU25-3604, updated on 30 Apr 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.
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.