Upwelling
The major upwellings in the ocean are associated with the divergence of currents that bring deeper, colder, nutrient rich waters to the surface. There are at least five types of upwelling: coastal upwelling, large-scale wind-driven upwelling in the ocean interior, upwelling associated with eddies, topographically-associated upwelling, and broad-diffusive upwelling in the ocean interior.
Haida Eddies
Elevated measurements of chlorophyll in eddy centers, as compared to surrounding water, indicate that eddies increase primary production, and can support multiple phytoplankton blooms within a single year. These blooms are not only caused by increased nutrients, but also the eddy's ability to transport biota from the coast into the eddy. Spring blooms are caused by sufficient light reaching the warm, nutrient-rich water contained in the middle of the eddy, due to anticyclonic rotation. A second bloom can occur once the eddy has moved closer to the deep ocean, when the outer reaches of the eddy can gather nutrient-rich water from either the coast or from an adjacent eddy. Coastal water transported by this outer ring advection can move from the coast into the eddy in six days which also allows for the rapid transport of coastal algae into the nutrient-rich eddy waters. A late summer bloom can occur if storms produce vertical convection of the mixed layer, causing it to deepen and trap nutrients from below into the region of primary production.