Once oil has entered the Gulf Stream, it may stay offshore in the Gulf Stream. There is some chance that it could move toward nearshore coastal waters and even reaching the coastlines of South Atlantic states. The amount of oil — if any — that reaches shore depends on several factors, including:
- the amount of oil in the Gulf Stream;
- prevailing winds;
- weather events such as storms or hurricanes;
- effects from additional eddies in the Gulf Stream; and
- influences from currents moving southward from the Mid-Atlantic Bight.
The risk of having oil come ashore would be greatest along the southern portion of Florida's east coast, due to the close proximity of the Florida coast to the Gulf Stream.
A second area in the South Atlantic that would be at higher risk for oil coming ashore is Cape Hatteras, North Carolina and the neighboring Outer Banks beaches, especially in the September through April time frame. Cape Hatteras is vulnerable because of both its proximity to the Gulf Stream and by onshore eddies and currents that may interact with the Gulf Stream near Hatteras.
Shorelines between south Florida and Cape Hatteras also could experience visible oil deposits, such as tar balls or oil pancakes, especially if coastal storms and/or wind patterns push the oil toward shore.
Movement of waters from the Gulf Stream to South Atlantic shorelines can vary greatly. If you frequent these shores, you might notice that some years there might be great amounts of Sargassum seaweed carried onto the beaches, or a flurry of Portuguese man-of-war sightings. But in other years, there might be few of these floating organisms washed ashore. Other floating debris – such as surface oil – would also be subjected to this variable ebb and flow of coastal currents.