AMOC Rate-Tipping Sandbox: Ocean Circulation Collapse Simulator

Atlantic Meridional Overturning Cross-Section [Equator → Subpolar North] 19.2 Sv

Overturning Transport History ψ(t) [Sv] Min: 19.2 Sv

Phase Portrait (ΔT vs ΔS) & Separatrix T: 4.0° | S: 1.0

Scenarios & Presets

Warming Ramp & Forcing Dynamics

Warming Duration (Transition Time) 45 yrs

Equilibrium Temp Delta (ΔT_eq) 3.2 °C

Freshwater Forcing Flux (Fw) 0.15 Sv

Calculated Warming Rate 0.71 °C/decade

EQUILIBRIUM OVERTURNING 1.4 Sv

MINIMUM OVERTURNING 2.1 Sv

CRITICAL RATE THRESHOLD 0.048 Sv/dec

QUASI-STATIC TIPPING PASS No

R-Tipping Mechanism: When heating occurs too swiftly, thermal stratification shuts down polar convective sinking before salt-advection feedbacks can restore density. Even if the target temperature is bistably viable, fast ramps provoke irreversible collapse.

AMOC Rate-Tipping Sandbox

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Read the explanation

The Atlantic Meridional Overturning Circulation is driven by density differences between warm tropical waters and dense subpolar sinks. In the Stommel model, transport equals alpha delta-T minus beta delta-S. A gradual temperature change allows salinity advection to stabilize the loop. Shortening transition duration to 45 years increases the heating rate to 0.71 degrees per decade, outpacing convective salt feedback. Thermal stratification halts subpolar downwelling. Transport plummets below six Sverdrups into an irreversible stagnant circulation state.