Keywords: Sargassum weeds closeup.jpg A closeup of a small mass of sargassum weed The numerous small round spheres are floats filled with carbon dioxide These provide buoyancy to the algae http //oceanexplorer noaa gov/explorations/02sab/logs/aug09/media/weeds html Ocean Explorer/NOAA 2002-08-09 Author PD-gov PD-USGov Unidentified Sargassum |