Kenneth Weiss and Usha Lee McFarling of the Los Angeles Times won for an ambitious series that examined the profound disturbances that have been occurring in the ecology of the world’s oceans.

“The Altered Oceans series was an unusual undertaking for a newspaper,” Weiss said. “there was no single dramatic event like a hurricane or tsunami. No mass human deaths. Instead, we looked at the slow creep of environmental decay — the kind of changes that most people never notice.”

The series described how industrial society has been overdosing the oceans with nutrients that have promoted the growth of harmful algae and bacteria. Plastic wastes have created a plague of floating detrius with widespread impact on sea life. The series also discussed how carbon dioxide is entering the oceans at a rate of nearly 1 million tons an hour, raising the acidity of seawater and threatening entire species. Natalie Angier, a Pulitzer Prize-winning science writer for The New York Times, said that the series gives “specificity and geography, a sense of place, to a part of the world we terrestrial species too often consider amorphous and unknowable.” She said the series shows “the passionate rigor we rarely see in newspapers these days.” Frank Roylance of the Baltimore Sun, called it “a most compelling series, ambitious, important and surprising in many aspects. The writing was first-rate, the enterprise impressive.”