Gagosian received a National Institutes of Health Postdoctoral Fellowship, completing research at the University of California at Berkeley between 1970 and 1972.
In 2006 and 2007, Gagosian served as the senior science advisor to the director of the Smithsonian National Museum of Natural History.
[8] He was a speaker at the India-U.S. Workshop on Science, Diplomacy and Policy in 2011[9] and at the Drager-Stiftung, Drager Foundation, EU-U.S. Conference Series on Sustainable Oceans in Hamburg, Germany, also in 2011.
[10] He also worked as associate editor of Geochimica et Cosmochimica Acta, was a faculty fellow of the World Economic Forum,[11] and was a Doherty Lecturer in Ocean Policy at the University of Virginia School of Law.
Gagosian chaired the Oregon State University President's Commission on Ocean, Coastal, and Earth System Futures in 2007,[12] and was a member of the U.S. National Commission for the United Nations Educational, Scientific, and Cultural Organization,[13] the Science Advisory Panel of the U.S. Commission on Ocean Policy,[14] the advisory board of the Hudson River Institute [15] the NOAA Science Advisory Board, and several other committees concerned with oceanography.