Whiting event

A whiting event is a phenomenon that occurs when a suspended cloud of fine-grained calcium carbonate precipitates in water bodies, typically during summer months, as a result of photosynthetic microbiological activity or sediment disturbance.

[5][6][1] Because whiting events affect aquatic chemistry, physical properties, and carbon cycling, studying the mechanisms behind them holds scientific relevance in various ways.

[7][2][8][9][10] Whiting event clouds consist of calcium carbonate polymorphs; aragonite tends to be the dominant precipitate, but some studies in oligotrophic and mesotrophic lakes show calcite is favored.

The three most common suggested causes for the phenomenon are: microbiological processes, re-suspension of marine or bottom sediments, and spontaneous direct precipitation from water.

[4] It's hypothesized that the extracellular polymeric substances (EPS) these microorganisms produce can act as seed crystals that provide a start for the precipitation process.

[2][7] In shallower waters, evidence supports that activity of local fisherman and marine life such as fish and certain shark species can disturb bottom sediments containing calcium carbonate particles and lead to their suspension.

An aerial view of a whiting event precipitation cloud in Lake Ontario.