The typically nutrient-poor waters around the Hawaiian Islands are often referred to as a “marine desert,” but a new study has identified surprising bursts of productivity off the northern coasts of the islands during winter. Using satellite data and regional ocean models, researchers found that these high-chlorophyll events, which signal increased marine life, are caused by small circular water currents called eddies on the opposite side of the island chain. These eddies stir up nutrients from deeper waters, which are transported around the islands to fuel phytoplankton blooms. This discovery reveals a new, far-reaching mechanism for nutrient distribution in otherwise nutrient-poor regions and sheds light on how ocean dynamics, like eddies, can significantly impact ecosystems. This work, published in JGR Oceans, provides key insights for managing and protecting ocean ecosystems.
The Climate Program Office’s Modeling, Analysis, Predictions, and Projections (MAPP) program supported author Brian Powell of the University of Hawai’i at Mānoa on this work through a grant aimed at modeling climate impacts on the predictability of fisheries and other living marine resources. The initiative represents a significant collaboration between the NOAA Fisheries and Research line offices and supports the application of modeling and other NOAA Research science to NOAA Fisheries applications. This project specifically addresses the climate impacts on marine health, productivity, and the sustainability and resilience of the marine ecosystem for the critical fisheries of Hawai‘i.
For more information, contact Clara Deck.