A team of MIT scientists have generated a detailed, three-dimensional "atlas" of the largest oxygen-deficient zones (ODZ) in the tropical Pacific. And though these ODZs make up less than 1 percent of the ocean’s total volume, they are a significant source of nitrous oxide, a potent greenhouse gas.
Source: https://soundcloud.com/mitnewsoffice/audio-article-oxygen-starved-water-atlas