The amount and types of fish that can survive and thrive in any given oceanic environment depend on many factors. Among these factors are temperature, salinity, oxygen, and nutrient levels. Because these factors are dependent on water temperature, either directly or indirectly, it is good practice for the fishing industry off the east coast of North America to follow the patterns and temperatures of the Gulf Stream.
Impact on Fisheries
As the Gulf Stream makes its way north the interaction with cooler waters can cause eddies to form. An eddy is a small whirlpool that forms counter to the direction of the main current. Eddies are not just surface phenomena, they can influence the flow of water at depths of several thousand meters. This kind of turbulence in the water can cause upwelling that can lead to changes in nutrient levels and the salinity of water. The patterns of the eddies are important to follow so that their impact on the concentration of fish or their predators can be tracked.
Clicking the red dots on this page will show how eddies form from the main current.
The following scientific papers may require an account to access their full text:
Gulf Stream frontal eddy influence on productivity of the southeast U.S. continental shelf by Thomas N. Lee, James A. Yoder, and Larry P. Atkinson
The influence of a Gulf Stream meander on the distribution of zooplankton biomass in the Slope Water, the Gulf Stream, and the Sargasso Sea, described using a shipboard acoustic Doppler current profiler by Ashjian, Smith, Flagg, Mariano, Behrens, and Lane
Eddies
Lionfish are warm water dwellers most commonly found in the western Pacific. Surprisingly, they have found their way into the Atlantic Ocean and the Gulf Stream's warm waters are helping them to survive and even reproduce. Because they have no natural predators in the Atlantic, their population has the potential to grow unchecked. Due to their diet of grouper and snapper, they are also a threat to the commercial fishing industry. Until their new habitat can adapt to their presence and develop competition, the fishing industry needs to be aware of their existence and monitor their whereabouts.
Read about what scientists found when they cut open the stomach of the Atlantic lionfish.
Learn about how NOAA believes the lionfish ended up in the Atlantic.
North Wall Effect
The North Wall Effect is the name given to the complex weather patterns that can result from the Gulf Stream hitting the cold North Atlantic waters in the fall and winter. Air masses passing over the relatively warm Gulf Stream waters can drop in temperature rapidly, leading them to rise quickly and cause dramatic low pressure areas. As air rushes in to these low pressure areas, the resulting winds can be directed in an opposite direction to the strong current. This opposition can cause large breaking waves. Ships can find themselves quickly thrust into a local weather system that is dangerous and unexpected. Staying knowledgeable about the Northern Wall Effect is important for fishing vessels or anyone else in traveling the North Atlantic in the cold months.
Powerpoint presentation explaining the formation of the North Wall, including dramatic pictures of potential wave heights.
Module/Tutorial for learning about the formation of the North Wall in the Gulf Stream and other similar phenomena in other parts of the world.