A comparison is made between series of high frequency internal waves observed in the St. Lawrence estuary from an aircraft and in a field program at a later date. Wave generation is associated with the propagation of a warm surface front during each ebb flow. The number of waves, as evidenced by surface slicks, is thought to vary as does the stability of the upper layer of the water column.
Ingram, R. G.. 1978. "Internal wave observations off Isle Verte." Journal of Marine Research 36, (4). https://elischolar.library.yale.edu/journal_of_marine_research/1452