Locations are shown in Fig. 2b. a–c, Temperature proxy records48,49,50 used for the Northwest Atlantic stack (Emerald Basin, Laurentian Fan and Gulf of St Lawrence), where model studies11, 12 indicate that AMOC weakening results in warming of surface and subsurface waters. d–g, Records used to reconstruct Northeast Atlantic SPG subsurface temperatures: d, Gardar drift51; e, combined South Iceland data (Bjorn drift)52, 53; f, Feni drift54; g, Eastern North Atlantic Central Water (ENACW), largely composed of waters formed in the eastern SPG55, 56. h, The high-resolution alkenone sea-surface temperature (SST) record from the North Iceland shelf57 was not included because it is not located within the open North Atlantic SPG (although it does also show, like the other Northeast Atlantic records, that the lowest temperature of the past 1,600 years occurred during the most recent century). Also shown for reference is the Rahmstorf central SPG SST reconstruction (based largely on terrestrial proxies)6.