It’s hard to think of Opilio season and crab fishing in January, without also thinking of the cold weather, the wind, and the dreaded ice on the Bering sea. And when we’re speaking of the Bering sea and the arctic as well, ice isn’t just ice. It’s much much more. Out there, ice comes in different shapes and appearances and therefore, has many different names. So how well do you know your ice, then?
(above is grease and small pancake ice)
From the Weather Factory: Sea ice forms from frozen seawater, as its name suggests, not compacted snow. Sea ice is dynamic: Like a plant or animal, it grows in stages, with different names for different stages. (photo above is small pancake ice).It changes with the seasons. And it is almost always on the move, impelled by currents and winds.
Sea ice forms when the temperature of the ocean surface falls below 28 degrees Fahrenheit. Unlike the calm surface of a lake, where ice forms in a gradually thickening sheet, the ocean surface is frequently stirred by waves. This leads to some interesting forms of ice…
(Image above is medium pancake ice)
Prior to ice being visible in the sea, the water thickens with loose ice crystals that don’t stick together because of the wind and movement of the water. It’s known as grease ice. But there’s other terms describing the same consistency of ice and water–Frazil, lolly ice, and slush. (At right is large pancake ice). Once the crystals start bonding and forming a shape, the ice forms pancakes, or pancake ice, a familiar term from having watched season 3 of “Deadliest Catch”. But pancake ice has stages: small, medium, and large pancake ice.
In the coldest part of winter, large pancake ice comes together and forms pack ice which is a thick crust of ice that covers much of the arctic. (to the left is image of pack ice) Pack ice is both formed at sea and locked to the shore. If the seas are very calm as the ice forms, the pack ice may be very flat but more often, it’s covered with very rough cut areas of ice caused by movement. But it shouldn’t be confused with ice floes. Pack ice may move with the movement of the water but it’s not free-floating chunks of ice.
So when Edgar Hansen and Matt Bradley of the F/V Northwestern took a little fieldtrip out on the sea ice to make snow angels, in season 3, what type of Bering sea ice do you think they were walking on? (Photo courtesy of Photo courtesy of Northwestern Brothers Marketing, LLC. www.fvnorthwestern.com)