The North Pacific Gyre, located in the northern Pacific Ocean, is one of five major oceanic gyres and covers most of the northern Pacific Ocean. It is Earth’s largest ecosystem, approximately 20 million square kilometers (over 7.7 billion square miles). The gyre’s circulation pattern is clockwise, as it is in the Northern Hemisphere. This region collects an unusually high amount of human-made marine debris; it is also called the Great Pacific Garbage Patch. Download larger version (jpg, 1.0 MB).