A water mass found in the Atlantic at depths between 1000 and 4000 m that can be traced from there into most other ocean basins. It is formed in the North Atlantic from some 5 Sv (5 × 10⁶ m³s⁻¹) of Atlantic Bottom Water entering through Denmark Strait and across the Scotland–Faeroe–Iceland Ridge. This water flows toward the Labrador Sea, entraining another 5 Sv from the eastern North Atlantic on its way. Another 5 Sv is added in the Labrador Sea by winter convection, giving a total of 15 Sv of NADW formation. The NADW formation process is the engine of the ocean conveyor belt, which makes NADW one of the most important water masses for today's climate.