Newswise — Scientists aboard a U.S. research vessel in the tropical Atlantic are taking advantage of the ship’s long-planned path through the Great Atlantic Sargassum Belt to take some of the first samples from a massive, ongoing bloom. Photos and video from the ship show the algae mats on the surface of the eastern Atlantic in the belt that extends from west Africa to the Gulf of Mexico.

This opportunistic sampling is taking place on the National Oceanic and Atmospheric Administration (NOAA) ship, Ronald H. Brown, which set sail from Port Suape, Brazil on March 6 as part of the Global Ocean Ship-based Hydrographic Investigations Program (GO-SHIP), funded by both NOAA and the National Science Foundation. The international program brings together scientists to develop a globally coordinated network as part of the global ocean/climate observing system. The Sargassum sampling illustrates how scientists aboard research vessels can quickly respond to oceanographic phenomena of wide-spread societal importance in real time.  “This has been a great way to leverage the measurements we were already making in the region” said Ellen Park, a graduate student who authored a blog on the team’s efforts.

Dennis McGillicuddy from Woods Hole Oceanographic Institution (WHOI), along with collaborators Chuanmin Hu and Brian Barnes from the University of South Florida, and Brian LaPointe from Florida Atlantic University, are tracking the Sargassum belt from satellite observations and analyzing these opportunistic samples, with the goal of studying the distribution of different species of Sargassum and measuring their elemental composition to better understand their origin. The nutrient supply feeding these blooms remains enigmatic, and hypothesized sources include upwelling/mixing, atmospheric deposition, and river runoff. These samples can help answer some of these critical questions.

Since 2011, when researchers first observed abnormally large accumulations of Sargassum in the tropical Atlantic Ocean, Caribbean and Gulf of Mexico, the blooms have gotten worse—with substantial economic costs associated with coastal inundation. While the algae support birds and sea life in the open ocean, it can have adverse impacts on environmentally and economically important ecosystems when they reach shore. As it starts to decay, Sargassum emits hydrogen sulfide fumes that impact human health.

Blog updates from the GO-SHIP mission.

Read more about the GO-SHIP expedition.

Get updates and itinerary information from the cruise.




About Woods Hole Oceanographic Institution

The Woods Hole Oceanographic Institution (WHOI) is a private, non-profit organization on Cape Cod, Massachusetts, dedicated to marine research, engineering, and higher education. Established in 1930, its primary mission is to understand the ocean and its interaction with the Earth as a whole, and to communicate an understanding of the ocean’s role in the changing global environment. WHOI’s pioneering discoveries stem from an ideal combination of science and engineering—one that has made it one of the most trusted and technically advanced leaders in basic and applied ocean research and exploration anywhere. WHOI is known for its multidisciplinary approach, superior ship operations, and unparalleled deep-sea robotics capabilities. We play a leading role in ocean observation and operate the most extensive suite of data-gathering platforms in the world. Top scientists, engineers, and students collaborate on more than 800 concurrent projects worldwide—both above and below the waves—pushing the boundaries of knowledge and possibility. For more information, please visit