By Tom Koritansky, Director of Park Operations

Winter in Lake County is a great time of the year to appreciate some truly spectacular scenery along the Lake Erie shore. When water temperatures become cold enough to produce ice, wind and waves along the shore can produce some very impressive formations. Ice that forms on large bodies of water like Lake Erie is classified by its thickness and age into five different categories. Four of these categories are capable of developing on Lake Erie.

New ice is the first category and describes water that has only recently frozen and is not yet completely solid. New ice first begins to form as water-saturated snow, commonly known as slush, or as frazil, which is collection of ice crystals similar to slush but appears shiny.

Newly forming slush is still thin enough that a resident beaver can swim through without trouble.

The next category in ice formation is called nilas ice which is a term used to describe an ice sheet up to four inches thick. This formative ice sheet is quite malleable and does not easily break because of wave action.

As ice forms on Lake Erie at different rates, new ice structures will also form alongside nilas. The translucent ice sheets in the previous photo overlooking Lake Erie are formations of grease ice along with nilas that appears white and gray. Grease ice forms in calm water from a thin layer of crystals and is shiny.

A distinct ice structure known as pancake ice forms in mainly rough water from combining clusters of slush or crystals into disc shapes or from melting ice sheets that break apart and form discs as they refreeze and collide with other ice sheets. The distinctive features of pancake ice discs are raised edges that form because of collisions with other discs. Most pancake discs range from one to three feet in diameter.

Broken nilas off the Lake Erie shore could form into pancake ice as the sheets collide with each other forming raised edges.

Conditions appear to be right for pancake ice formation from this sheet of nilas. Notice a few pancake discs are already beginning to form.

Ice that has thickened between four and 12 inches is known as young ice. This is a transition stage between nilas and the next stage of development known as first-year ice. This thicker ice is not nearly as flexible as nilas and will break under wave action. Sheets of young ice that wash ashore often provide the foundation for impressive ice dunes.

Ice that is thicker than 12 inches but does not have more than one-year’s worth of growth is known as first-year ice. This is the last stage of growth that occurs on Lake Erie because any ice that develops over winter will melt by mid spring. If ice on the lake were to ever survive the summer months, whatever ice remained would then be known as old ice, which is the last stage of development.

Our frozen Lake Erie resembles the arctic tundra as a sole coyote traverses a thick layer of first-year ice on a cold winter evening.

Some of the most impressive formations happen when first-year ice forms on the lake. Most notable are dunes that form as ice accumulates near shore. These near-shore accumulations form when air temperatures are below freezing and water temperatures approach freezing. Ice washing ashore from wave action begins to accumulate. These accumulations grow as freezing wave spray and precipitation fuse other pieces of ice together. Dunes can grow to great sizes with some truly dramatic shapes depending on the amount of wind, wave action and time they have to form.

Ice dune formation as young ice washed ashore has refrozen with a fresh accumulation of snow.

Fully formed ice dunes protect the shoreline from wave erosion during winter months. Ice beneath these dunes has been covered by accumulations of snow and slush.