Warmth of the Subpolar North Atlantic Ocean During Northern Hemisphere Ice-Sheet Growth

Two 10,000-year periods of Northern Hemisphere continental ice-sheet growth stand out prominently within the last full interglacial-to-glacial cycle. During the first half of each rapid ice-growth phase, the subpolar North Atlantic from 40 degrees N to 60 degrees N maintained warm sea-surface temperatures comparable to those of today's ocean. The juxtaposition at latitudes 50 degrees N to 60 degrees N of an "interglacial" ocean alongside a "glacial" land mass, particularly along eastern North America, is regarded as an optimal configuration for delivering moisture to the growing ice sheets.