Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections
2025/08/11 by Sybren Drijfhout, Joran Angevaare, Jennifer Mecking +2 · 13 voices · 11 citations
Earth and Planetary Sciences · Environmental Science · #Geology and Paleoclimatology Research #earthquake and tectonic studies #Methane Hydrates and Related Phenomena
paper · pdf · doi:10.1088/1748-9326/adfa3b
Abstract
Abstract Several, more recent global warming projections in the coupled model intercomparison project 6 contain extensions beyond year 2100–2300/2500. The Atlantic meridional overturning circulation (AMOC) in these projections shows transitions to extremely weak overturning below the surface mixed layer (<6 Sv; 1 Sv = 10 6 m 3 s −1 ) in all models forced by a high-emission (SSP585) scenario and sometimes also forced by an intermediate- (SSP245) and low-emission (SSP126) scenario. These extremely weak overturning states are characterised by a shallow maximum overturning at depths less than 200 m and a shutdown of the circulation associated with North Atlantic deep water formation. Northward Atlantic heat transport at 26°N decreases to 20%–40% of the current observed value. Heat release to the atmosphere north of 45°N weakens to less than 20% of its present-day value and in some models completely vanishes, leading to strong cooling in the subpolar North Atlantic and Northwest Europe. In all cases, these transitions to a weak and shallow AMOC are preceded by a mid-21st century collapse of maximum mixed-layer depth in Labrador, Irminger and Nordic Seas. The convection collapse is mainly caused by surface freshening from a decrease in northward salt advection due to the weakening AMOC but is likely initiated by surface warming. Maximum mixed-layer depths in the observations are still dominated by internal variability but notably feature downward trends over the last 5–10 years in all deep mixing regions for all data products analysed. This could be merely variability but is also consistent with the model-predicted decline of deep mixing.
Citations
Cited by
Discussions
- ➡ Our paper is open access here: doi.org/10.1088/1748... Are you interested in the #AMOC? ➡ My popular article in Oceanography magazine: tos.org/oceanography... ➡ My recent talk on YouTube: youtu.be/Z [bsky, 155 points, 3 comments]
- Una cosa interesante de este artículo es que, bajo escenarios de altas emisiones (que no deben ser tan diferentes al desbalance radiativo que estamos viendo ahora), los diversos modelos coinciden en q [bsky, 45 points, 0 comments]
- Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections doi.org/10.1088/1748... via @ioppublishing.bsky.social [bsky, 3 points, 0 comments]
- Important study led by #TipESM researcher Sybren Drijfhout focused on #AMOC. Findings show that deep convection stops in many models in the next 10-20 years, which in most cases triggers AMOC shutdown [bsky, 2 points, 1 comments]
- Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections doi.org/10.1088/1748... via @ioppublishing.bsky.social [bsky, 2 points, 0 comments]
- The collapse of the Atlantic meridional overturning circulation (AMOC), a critical ocean current, can no longer be considered a low-likelihood event. This is according to a study published on August 2 [bsky, 2 points, 0 comments]
- ✨ Wrapping up 2025 with our Top 5 read articles! At #4: ‘Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections'. This calls for climate policy and p [bsky, 1 points, 0 comments]
- Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections doi.org/10.1088/1748... via @ioppublishing.bsky.social [bsky, 1 points, 0 comments]
- #AMOC #StefanRahmstorf Original open access article Drijfhout et al. 28 August 2025, Environ Res Lett 20(9):094062 Shutdown of northern Atlantic overturning after 2100 following deep mixing collaps [bsky, 1 points, 0 comments]
- ** Sybren Drijfhout, et al. “Shutdown of Northern Atlantic Overturning after 2100 Following Deep Mixing Collapse in CMIP6 Projections.” Environmental Research Letters, 11 Aug. 2025, doi.org/10.1088/17 [bsky, 0 points, 0 comments]
- Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections doi.org/10.1088/1748... via @ioppublishing.bsky.social [bsky, 0 points, 0 comments]
- Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections doi.org/10.1088/1748... via @ioppublishing.bsky.social [bsky, 0 points, 0 comments]
- Shutdown of northern Atlantic overturning after 2100 following deep mixing collapse in CMIP6 projections doi.org/10.1088/1748... via @ioppublishing.bsky.social [bsky, 0 points, 0 comments]
Related