Human activity has tainted all but 3.7 percent of the world’s oceans, and 41 percent of the world’s waters have been heavily impacted, says a new study in Science. A graphic map illustrates in all-too-clear terms that the briny deep has taken a terrible toll from 17 human threats, including climate change, overfishing, fertilizer runoff, coastal development, and shipping pollution. Only a few small areas near both poles remain relatively pristine — though, according to one coauthor, “they are not untouched.” In addition, a separate study in Science found that low-oxygen dead zones off the U.S. West Coast were unprecedented before they began showing up regularly in 2002, that in 2006 some areas lacked oxygen altogether, that dead zones will likely persist and possibly get worse, and that climate change is likely to blame.