Climate scientists claim Gulf Stream could be near collapse
7 days ago
- #oceanography
- #AMOC
- #climate change
- Climate models project a slowdown of the Atlantic Meridional Overturning Circulation (AMOC) under anthropogenic greenhouse warming.
- A distinctive temperature fingerprint in the equatorial Atlantic signals AMOC changes, with mid-depth (1000–2000 m) warming occurring within a decade via baroclinic Kelvin waves.
- Mid-depth temperature changes in the equatorial Atlantic are more reliable indicators of AMOC slowdown than surface proxies on decadal and longer timescales.
- Observations show robust mid-depth warming in the equatorial Atlantic since 1960, emerging from natural variability in the early 2000s, suggesting AMOC slowdown began in the late 20th century.
- The equatorial Atlantic acts as a crucial crossroads for AMOC anomalies to propagate to other oceans via oceanic Kelvin waves.
- OGCM experiments highlight that AMOC slowdown drives upper and mid-depth warming in the equatorial Atlantic, with a vertical minimum at 1000 m.
- The signal-to-noise ratio for mid-depth equatorial warming is high, making it a reliable metric for detecting AMOC changes.
- The study suggests an AMOC weakening of ~2 Sv since the 1950s based on observed mid-depth warming, assuming models accurately capture the AMOC-equatorial warming relationship.