Preliminary Research

A polynya is an area of open sea water surrounded by ice. Polynyas are formed in two ways, the first is when the SST (sea surface temperature) never drops below freezing and the water in that area does not form ice. This produces what is known as a sensible heat polynya, the alternative process of polynya formation creates what is known as a latent heat polynya. A latent heat polynya is formed when an area of sea ice is already in existence, connected to the coast of a landmass, but is then pushed away from the land by katabatic winds.

Katabatic winds flow downward from atop hills due to the pressure gradient and the pull of gravity. Air moves from areas of high concentration to areas of low concentration; so the pressure gradient, caused by the air at higher altitudes being significantly cooler than the air at sea level, forces air downward.

Sea ice formation occurs when ocean water cools below the freezing point, but in the development, leaves the salt behind, in a process called brine rejection. Since water’s density is determined by its salt concentration and temperature, brine is heavier than the ice that forms from it so the ice floats on top of the ocean. The spatial relationship between the lighter freshwater and heavier saltwater is mimicked throughout the ocean depths. Deeper ocean depths are cooler and saltier than the water above it. The salt left behind in brine rejection eventually sinks when it becomes too dense to stabilize in the upper stratus of the ocean. Consequently, the lower ocean depths accumulate a buildup of salt and become more dense, which creates a density gradient to the surrounding water. Due to the density gradient, the water is displaced horizontally. The continuous movement of dense sea water, first downwards vertically then out horizontally, generate oceanic currents. If the rate of sea ice formative processes were altered, a change in oceanic currents would undoubtedly ensue.