Gulf Stream Collapse (AMOC Weakening)

A full Gulf Stream collapse could cool Western Europe by 5-10°C while scrambling global monsoon patterns, with AMOC weakening already detected at a 15% reduction since 1950. Paleoclimate evidence suggests such a shutdown occurred 11,000 years ago, reversing warming trends within decades—an abruptness that outpaces #3 Amazon dieback in its capacity to disrupt agriculture within a single generation. Current models disagree on collapse probability by 2100, ranging from 10-50% under high emissions, a larger spread than sea level rise estimates. The resulting winter temperature plunge would dwarf the 2-3°C European warming already observed, creating a stark regional contrast to global heating. Strategic consequences include energy demand spikes 40% above current norms for northern nations, while equatorial monsoon failures would threaten food security for 1.3 billion people across Asia and Africa.