but david helvarg says we should call it planet ocean.fter all, water covers more than 70% of the globe. >> and we get so much from the ocean in terms of recreation and transportation, trade, energy and just that sense of awe and wonder of being part of this great blue marble that i think it's only sensible that we give something back. >> reporter: david is the president of blue frontier, an environmental organization. he wrote this book, "50 ways to save the ocean." >> the first of the 50 ways to save the ocean i say is go to the beach because we protect what we love. but when you go there, make sure you pack out everything you pack in. >> reporter: especially those soda and water bottles. or those bags you bring them in. one of the biggest polluters of the ocean is plastic. even when we're not at the beach, using less plastic can help keep our oceans clean. >> every year americans throw a billion plastic water bottles away. so you know, work for clean tap water. you know, don't use plastic. recycle. and when you go to the store, take a