Shuga by the Seashore

February 20, 2018



Photographer: Rob Sheridan 
Summary Author: Rob Sheridan 

Sea ice at the winter shoreline takes countless fascinating configurations as it forms melts and reforms creating frazil, grease, nilas, pancake, rafting, ridging, and sheet patterns. Many factors play into this process including rate and depth of temperature fall, rise and fall of tides, salinity, height and energy of wave action, humidity and precipitation, direction and strength of prevailing winds, and interactions with the shoreline and bottom. The term shuga ice describes spongy white lumps a few centimeters across which form in rougher water. These two photos (bottom photo is a close up) illustrate shuga ice that formed above the usual shoreline during a bomb cyclone (and blizzard) in coastal New England on January 5 and of 2018. Note that the storm surge associated with this powerful Nor'easter occurred at high tide. Subsequent tides didn't reach near this level, preserving the fascinating formation for a few days in the bitter cold air that immediately followed the storm. Photo taken on January 7, 2018.

Photo Details: Both images - Camera: Apple iPhone 5s; Exposure Time 0.0001s (1/8264); Aperture ƒ/2.2; ISO equivalent 40; Focal Length (35mm) 29.