https://www.washingtonpost.com/news/energy-environment/wp/2016/08/31/how-sea-ice-is-making-the-southern-ocean-less-salty-and-what-that-might-mean-for-the-rest-of-the-world/?utm_term=.508241e0b68d

Saltinity important to ocean processes: 

“These processes are important drivers of ocean currents all over the world. The salty water created by sea ice formation is denser than fresh water, so it has a tendency to sink to the bottom of the ocean. In doing so, it helps push the water below it forward along the sea floor, creating a current that runs north toward the equator. As the water warms up, it rises to the surface and eventually runs back toward the poles. This process helps carry heat and nutrients around the world.”

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