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Författare/Upphovsman: Tom Kredatus, Licens: CC BY-SA 3.0
Snow rollers, rare weather phenomena, Columbus, Ohio
Snow rollers were photographed at the Lincoln Christian College, by NWS
personnel in Lincoln. Tracks that the rollers took can be seen trailing behind.
(The snow rollers generally moved in an eastward direction.)
Författare/Upphovsman: Guy-from-Ohio, Licens: CC BY-SA 3.0
Snow Rollers in Eastern Ohio along US 322 1-29-2014
_(Newark%2c_Ohio%2c_USA)_52_(46832711081).jpg)
Författare/Upphovsman: James St. John, Licens: CC BY 2.0
(photo by Mary Ellen St. John)
Snow rollers are very rare sedimentary structures. They only form in snowy sediments. Snow is a type of sediment of cold, meteoric origin and composed of the mineral ice (H2O). Snow rollers are layered cylindrical structures formed as moderately strong winds blow across snow surfaces. They are rare because several specific conditions must be met (e.g., see Reed, 1933; Cameron, 1949; Hornstein, 1951). Depressed trails occur behind snow rollers, showing the direction of movement. Trails start out small and narrow, but widen toward the actual snow roller. The widening trail reflects the growth of the snow roller - each end of the cylinder is conically embayed.
The example seen here formed in late January 2014 in Ohio. This is semi-natural, because the field in which it occurs was clear-cut long ago. Almost all of Ohio's natural landscape was originally forested.
Locality: field along the northern side of Sharon Valley Road, west of Country Club Drive intersection, western side of Newark, Licking County, east-central Ohio, USA
References cited:
Cameron (1949) - Snow rollers - nature at play. Weatherwise February, 1949: 12-13.
Hornstein (1951) - Snow rollers. Weather 6(6); 168-169.
Reed (1933) - Snow rollers. Monthly Weather Review December, 1932: 252.