Sampling Open Ocean Eddies in the Central North Pacific Ocean
Come along for the ride! Scientists are on a research mission to learn more about open-ocean mesoscale eddies and their impact on pelagic ecosystems in the Central North Pacific.
A team of scientists from the Pacific Islands Fisheries Science Center are out to sample open-ocean eddies, rotating masses of water in the ocean, and fronts on the NOAA Ship Oscar Elton Sette. Their goal is to better understand differences in ecosystem structure inside and outside these eddies. While the ocean may seem homogenous, mesoscale eddies provide a three-dimensional structure across many trophic levels. Eddies spin either clockwise or counter-clockwise, can span between 10–100 kilometers, and may last for months.
In the northern hemisphere, counterclockwise (cyclonic) eddies bring up cold, nutrient rich waters from deep in the ocean towards the sunlit surface where phytoplankton can take advantage of the nutrients and grow. In clockwise (anticyclonic) eddies, warm surface water is concentrated in the center of the eddy. Regardless of the direction of the spin, eddies create pockets of high productivity that span many trophic levels. For oceanic top predators, like tuna, eddies are potential hotspots for their prey— meaning tuna and other predators may seek out eddies as foraging grounds. The samples and data collected during this expedition will advance our understanding of the ecosystem that supports tuna, other pelagic predators, and protected species like whales. Efforts like this, progress us towards Ecosystem-Based Fisheries Management and further NOAA’s mission of stewardship of the nation's ocean resources and their habitat.