Atlantic Fisheries Research Document 1996/137

Marine environmental conditions in the northwest Atlantic during 1995 potentially impacting Atlantic salmon

By K. Drinkwater

Abstract

This paper examines marine environmental conditions during 1996 in the Northwest Atlantic that potentially impact upon Atlantic salmon. Of particular interest is the Labrador Sea region where many of the salmon that spawn in Canadian east coast rivers overwinter. As background, a general review of the relationship between atmospheric conditions, sea ice, and ocenaographic events in the Labrador Sea is presented. In years when the large-scale atmospheric circulation intensifies (more intense Icelandic Low and Bermuda-Azores High and a high NAO (North Atlantic Oscillation) index), there tends to be increased northwest winds over the Labrador Sea, colder air temperatures, more ice, and colder ocean temperatures. When the circulation weakens, the northwest winds tend to be weak, air temperatures are warm, there is less ice and ocean temperatures are also warm. During 1995, air temperatures, sea ice and ocean temperatures indicated relatively cold conditions in the Labrador Sea, continuing a trend that has persisted for over a decade. However, slight warming and less ice suggest moderating conditions. In the Gulf of Maine, where inner Bay of Fundy salmon stocks are believed to overwinter, sea surface temperatures were generally above their long-term normals. This is in contrast to the Scotian Shelf, where temperatures have been below normal.

Complete document (PDF, 2,356 KB)

Accessibility Notice

This document is available in PDF format. If the document is not accessible to you, please contact the Secretariat to obtain another appropriate format, such as regular print, large print, Braille or audio version.