MARCUS ERIKSEN AND ANNA CUMMINS

THE AMOUNT OF PLASTIC WASTE swirling around in the world’s oceans appears to be growing. The so-called Great Pacific Garbage Patch in the North Pacific Ocean has gotten a lot of attention, but plastic pollution is a global problem, according to Marcus Eriksen and Anna Cummins, a pair of eco-educators, adventurers, and marine researchers with the nonprofit Algalita Marine Research Foundation, based in Long Beach, Calif. The two outdoor enthusiasts are on a mission to document just how much plastic debris is in the oceans and, along the way, educate the public. After getting married last June, the couple started an ambitious effort called the 5 Gyres Project (5gyres.org). A gyre is a massive system of rotating ocean currents that acts like a whirlpool in which plastic trash tends to accumulate. There are five major gyres of the world, located in the North Pacific, South Pacific, North Atlantic, South Atlantic, and Indian Oceans. The ...