Nelsen is the man behind surfonomics—the scientific breakdown of surfing’s economic importance. The son of a marine science teacher, Nelsen remembers performing seawater buoyancy and salinity tests in his father’s lab. In grad school, Nelson realized he could combine his passion for the ocean and science with his recreational pastime—surfing—in his doctoral thesis. He had a hunch the monetary value of healthy coastal ecosystems and surf breaks was an under-utilized tool in coastal conservation. “One of my proudest accomplishments is that surfonomics is now being applied to coastal preservation efforts around the world,” says Nelsen. He’s now CEO of Surfrider Foundation, the largest U.S non-profit dedicated to marine conservation.