Some thoughts on the freezing and melting of sea ice and their effects on the ocean

bution No. 679. The views expressed herein are those of the authors and do not neces-sarily reflect the views of NOAA or any of its subagencies. Abstract. The high-latitude freezing and melting cycle can variously result in haline con-vection, freshwater capping, or freshwater injection into the interior ocean. An example of the latter process is a secondary salinity minimum near 800 m depth within the Arctic Ocean that results from the transformation on the Barents Sea shelf of Atlantic water from the Norwegian Sea and its subsequent intrusion into the Arctic Ocean. About one-third of the freshening on the shelf of that initially saline water appears to result from ice melt, although the actual sea ice flux is small, only about 0.005 Sv. A curious feature of this process is that water distilled at the surface of the Arctic Ocean by freezing ends up at mid-depth in the same ocean. This is a consequence of the ice being exported south-ward onto the shelf, melted, and then entrained into the northerly Barents Sea through-flow that subsequently sinks into the Arctic Ocean. Prolonged reduction in sea ice in the region and in the concomitant freshwater injection would likely result in a warmer and more saline interior Arctic Ocean below 800 m