water in the inner part of the Lincoln Sea shelf, where the temperature and salinity profiles increase from the surface to the seafloor. The second involves the water covering the outer part of the shelf, including the slope; the waters here hold attributes similar to those in the Canadian basin and thus not unlike those from the Pacific. The third includes the waters north of the shelf's slope. These waters protrude into the Arctic basin's large-scale circulation, and so their characteristics appear to change over to those found in the Eurasian basin. Along the continental margins of the Arctic Ocean basin, narrow boundary currents are hypothesized to house intense large-scale advection that is critical in the general circulation of Arctic waters. One of these boundary currents resides along the sloping edge of the Lincoln Sea shelf, between the base and the shelf break at approximately 1600 m. The current's strength is 5–6 cm/s, according to long-term measurements. Assuming an undercurrent with an average strength of 4 cm/s and dimensions of 50 km in length and 1000 m in depth, the transport delivered over the slope of the Lincoln Sea shelf would be 2 Sverdrups, where 1 Sverdrup equals 10^6 m^3/s. Measurements reveal that this undercurrent shares comparable features to that found in the Beaufort Sea, whose boundary currents are responsible for large-scale advection within the Arctic circulation. Because of this mutual oceanographic behavior, it has been determined that the Lincoln Sea undercurrent continuously flows and is a component of the boundary current system that spans between Alaska and Greenland along the northern shores of the Canadian archipelago. Sea Ice In May 2004 and 2005, electromagnetic measurements from helicopters revealed insights into the thickness of the sea ice in the Lincoln Sea and surrounding waters. With thicknesses ranging between 3.9 and 4.2 m, multi-year ice dominates south of 84°N. First-year ice, with thicknesses ranging between 0.9 and 2.2 m, denotes the refreezing of the Lincoln Polynya ice. These helicopter measurements concur with satellite-based radar imagery as well as ground-based electromagnetic observations. Drifting buoys have exposed a southward drift of sea ice toward Ellesmere Island and Nares Strait. It has been concluded that shear in the Lincoln Sea narrow boundary current plays an important role in shifting and thus removing sea ice from the Arctic region. The majority of sea ice export takes place on the eastern edges of the Arctic Ocean