Quasi-Stationary Front

A quasi-stationary front is an ocean front that holds its position in a region for weeks to seasons rather than drifting freely. Such fronts are pinned by bathymetry, tidal mixing, or persistent circulation features: tidal-mixing fronts at the shelf-stratification boundary, shelf-break fronts, and the recurrent thermal and chlorophyll fronts of marginal seas all qualify. The Yellow Sea, for instance, rings its Cold Water Mass with quasi-stationary thermal fronts each summer. Because they recur in the same place, these fronts concentrate nutrients and plankton predictably, making them reliable feeding grounds and useful reference features for survey planning.