RISING TIDES, TROUBLED WATERS

The ocean is undergoing unprecedented changes. What does it mean for marine life, the planet, and us?

- JEFF GOODELL

THE BLOB WENT UNNOTICED AT FIRST. In the summer of 2013, a high-pressure ridge settled over a Texas-size area in the northern Pacific, pushing the sky down over the ocean like an invisible lid. The winds died down, and the water became weirdly calm. Without waves and wind to break up the surface and dissipate heat, warmth from the sun accumulated in the water, eventually raising the temperature by 5 degrees Fahrenheit — a huge spike for the ocean.

When scientists noticed this temperature anomaly in the satellite data, they had never seen anything like it. Everyone knew about heat waves on land, but in the ocean? “As the Earth heats up, the ocean is changing in very dramatic ways,” says Jane Lubchenco, a marine ecologist and former head of the National Oceanic and Atmospheric Administration. “It is less predictable, and we are seeing more surprises. The heat waves are one of those surprises.”

Nick Bond, a climatologist at the University of Washington, nicknamed the Pacific heat wave “the Blob,” after a campy 1958 sci-fimovie about a gelatinous monster that arrives on Earth in a meteor and eats up a small town. But this Blob would turn out to be far more deadly than anything Hollywood imagined.

The hot water killed the phytoplankton — a form of microscopic algae — that live in the top few hundred feet of the ocean. The tiny organisms that feast on them starved, including krill, the small shrimplike creatures that swarm the ocean by the billions and are the preferred food for whales, salmon, seabirds, and many other creatures. The population of herring and sardines, an important food source for many larger fish and marine mammals, also declined. By killing phytoplankton, the Blob disrupted the entire Pacific food chain.