This occurs when the Trade Winds and ocean currents, especially the South Equatorial Current
, become abnormally strong.
These anomalies were an enhancement of the northern branch of the westward South Equatorial Current
(SEC) as seen in December 2014 (Dohan et al.
This profile shows the presence of typical warmer Equatorial Current
waters, whilst sharp anomalies can be associated with the influence of wind on them.
In the north Atlantic, for example, the trade winds drive the North Equatorial current
roughly from West Africa to the West Indies before the water flow curves north to become the Gulf Stream, running north and east across the Atlantic.
The Galapagos Islands are also at the convergence of three different oceanic currents (the warm South Equatorial current
, the cold Equatorial undercurrent [Cromwell current] and the Peru or Humboldt current); together with the effect of the trade winds from the southeast, this means the islands have a very seasonal climate.
derasa using a mixed-model approach demonstrated similar strong trends in gene flow along island chains, perpendicular to the South Equatorial Current
[ILLUSTRATION FOR FIGURES 5B,C OMITTED]).
The diatoms creating the streak in the Pacific congregate and thrive at the convergence of the North Equatorial Countercurrent and the cooler, denser water of the South Equatorial Current
sinking below it, the scientists assert.
The eastward flow of a major equatorial current
in the Pacific Ocean was interrupted and reversed for about a month in late 1987, and may have signalled the end of the 1986-87 El Nino event, according to National Oceanic and Atmospheric Administration (NOAA) oceanographers.
Wyrtki demonstrated that this was not the case and instead hypothesized that, for a 1-2-year period before El Nino, stronger than normal trade winds in the central Pacific would pile up excess warm water in the western basin via an intensified westward-flowing South Equatorial Current
Scientists believe the bottle traveled north through the South Pacific Gyre off the Galapagos Islands, then into the East Australian Current, before approaching the South Equatorial Current
and possibly weaving through Fiji, Vanuatu and New Caledonia.
While the moderate equatorial current
known as El Nino could warm the ocean and atmospheric temperatures, climatologists warned that a major event such as a volcano could severely cool its impact.