Extended Data Figure 1: Bottom density contrasts and basin masks.
From: Abyssal ocean overturning shaped by seafloor distribution
a, Shaded bottom neutral density field, with the 4 km bathymetric contour overlaid in black. b, Basin masks employed for Extended Data Figs 2, 3, 4. The dianeutral circulation, which is essentially confined to the near-bottom, can largely be tracked from the bottom density distribution. The four main northward paths of AABW are identified in the western Indian, eastern Indian, western Pacific and western Atlantic oceans. The southeastern Pacific, east of the East Pacific Rise, hosts inflow of Circumpolar Deep Water71,72 (see Extended Data Fig. 2). Large bottom density differences across connected, AABW-ventilated sub-basins largely reflect the efficient consumption of the densest through- and overflowing waters at deep straits and sills. The Chain (CFZ), Romanche (RFZ) and Vema (VFZ) fracture zones linking the abyssal eastern and western Atlantic are indicated.
