Climate variability on the Scotian Shelf during the 1990s

The temperature and salinity conditions of the waters on the Scotian Shelf during the 1990s are described. Three major features are highlighted. First is the presence of cold subsurface waters throughout much of the 1990s in the northeast and nearshore regions of the Shelf. The principal cause of these cold conditions, initially established in the mid-1980s, is thought to be along-shelf advection from the Gulf of St Lawrence and off southern Newfoundland with the possibility of some contribution from local in situ cooling. The second major feature was caused by the arrival in 1997-1998 of cold Labrador Slope water along the shelf break, which subsequently flooded the lower layers of the central and southwestern regions of the Scotian Shelf. While this event produced the coldest near-bottom conditions in these Shelf regions since the 1960s it was of short duration, lasting only for approximately one year. Finally, the changes in the near-surface waters of the Scotian Shelf are described. O f particular relevance were the extremely warm surface temperatures in the late 1990s and the strong vertical stratification throughout the decade. The latter was a result of record low salinities in the near-surface waters that appear to be advected onto the Shelf from off the G rand Banks. The impact of these changes in ocean climate on some of the Shelf fish stocks is briefly discussed.Description not yet available.

Article from Marine Science Symposia Vol. 219 - "Hydrobiological variability in the ICES Area, 1990-1999", symposium held in Edinburgh, 8-10 August 2001. To access  the remaining articles please click on the keyword "MSS Vol. 219".