Replication Data for: "Polar phasing and cross-equatorial heat transfer following a simulated abrupt NH warming of a glacial climate"

MITgcm model output and plot scripts corresponding to the manuscript "Polar phasing and cross-equatorial heat transfer following a simulated abrupt NH warming of a glacial climate" Abstract "A lag of about 200 years between abrupt Greenland warming and maximum Antarctic warming characterizes past glacial Dansgaard–Oeschger events. In a modeling study, we investigate how the cross-equatorial oceanic heat transport (COHT) drives this phasing during an abrupt Northern Hemisphere (NH) warming. We use the MITgcm in an idealized continental configuration with two ocean basins, one wider, one narrower, under glacial-like conditions with sea ice reaching mid-latitudes. An eccentricity-related solar radiation anomaly imposed over 100 years to trigger an abrupt NH warming and sea-ice melting. The Hadley circulation shifts northward in response, weakening the NH trade winds, subtropical cells (STCs), and COHT in both ocean basins. This induces heat convergence in the Southern Hemisphere (SH) ocean subsurface, from where upward heat release melts sea ice and warms SH high-latitudes. Although the small-basin meridional overturning circulation also weakens, driven by NH ice melting, it contributes at most one-third to the total COHT anomaly, hence playing minor roles in the SH and NH initial warming. Switching off the forcing cools the NH; by contrast, heat release continues from the SH ocean subsurface via isopycnal advection-diffusion and vertical mixing, driving further sea ice melting and high-latitude warming for about 50–70 more years. A phasing in polar temperatures resembling reconstructions thus emerges in the model, linked to changes in the STCs’ COHT, and SH ocean heat storage and surface fluxes. Our results highlight the potential role of atmosphere circulation and wind-driven global ocean circulation in the NH–SH phasing seen in DO events."