Overview

• In a multi-author study published in Environmental Research Letters, researchers extended CMIP6 simulations to the years 2300–2500 and found tipping behavior emerging in many models within the next one to two decades.
• The models show the circulation slowing by century’s end in all high-emissions pathways and in some medium or low pathways, with collapses occurring later in the extended runs.
• The study reports collapses in roughly two-thirds of very high-emissions scenarios, about one-third of moderate scenarios, and around one-fifth of low scenarios.
• Authors caution the risk may be underestimated because many models omit additional freshwater from accelerating Greenland ice-sheet melt, while direct monitoring since 2004 is short and paleo-records indicate unprecedented weakness over the past millennium.
• Projected regional impacts include cooler European winters, drier conditions, stronger storms, and roughly 0.5 to 1 meter of extra local sea-level rise, though other recent work found no collapse by 2100, underscoring ongoing scientific debate.