Dianna Cohen, an artist and environmentalist, remembers well how her hometown of Los Angeles changed in the 1970s when local grocery stores started offering plastic bags in addition to paper ones. During her family’s frequent trips to the beach, she could see the effect of that shift on the surrounding environment—something that inspired her to use plastic materials in her visual-art projects in college.
Later on, Cohen resolved to put her energy into reducing waste. She began an effort to clean up the Great Pacific Garbage Patch, a gyre in the middle of the ocean filled with marine debris. She soon discovered that the “patch” wasn’t actually an island at all, but a vortex of water clogged with plastic waste. Discoveries such as this and others led Cohen to co-found the Plastic Pollution Coalition (PPC), a nonprofit that aims to reduce the use of disposable plastic. The organization has started initiatives such as Refill Revolution, which works with music festivals to encourage concertgoers to use metal cups instead of plastic ones.
Cohen’s activism is inspired by, among others, Sylvia Earle, an oceanographer and a National Geographic explorer in residence. Cohen first met Earle at a book signing and says the biologist’s work convinced her of the importance of protecting the ocean and its inhabitants. I spoke with Cohen, about Earle and environmentalism more broadly, for The Atlantic’s series on mentorship, “On the Shoulders of Giants.” The following conversation has been edited and condensed.