Earlier in the year, Seattle-based photographer Kaylyn Messer stumbled upon a Facebook comment about an ice circle that had been spotted in the current of the nearby Middle Fork Snoqualmie River. Realising how precious and rare a sight this was, she hightailed it over with gear in tow, and captured the video, above.
According to geography portal Geo Lounge, ice circles are a rare phenomenon occurring in rivers, streams and creeks, mainly in North America and Scandinavia. They are often quick-forming and quick to disappear. "Ice circles form in eddies of slow-moving rivers when the water temperature is at freezing level or lower. The river has to be moving at a very specific rate; too fast and the eddy is disrupted, too slow and the eddy freezes along with the rest of the river, stream or creek. The current in the river has to be slow enough that an eddy forms and freezes slowly over a period of time, causing the circle of ice on the surface to freeze and continue moving in the pattern of the eddy."