Deep Trouble

July 9, 2017
By Damond Benningfield

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Anglerfish live in deep waters. Credit: National Oceanic and Atmospheric Administration

Life in the deep ocean could be headed for deep trouble. The food supply could shrink dramatically, starving many of the organisms that live on the ocean floor.

Living in the deep ocean is tough already. It’s cold and dark there, with far less food than at shallower depths. But our changing climate could make things even more difficult.

A recent study looked at various models of how the atmosphere and oceans could change by the end of the century. The study team then projected what those changes could mean for life in the deep ocean -- anything below about 650 feet.

Depending on the exact location and depth, temperatures in the deep ocean are projected to rise by about two degrees to eight degrees Fahrenheit. The level of acidity is expected to go up as well, while oxygen levels are expected to go down. Those changes mean that organisms at those depths will need to expend more energy to survive.

Unfortunately, though, they’ll have less food to fuel them. Most of the food in the deep ocean comes from above -- dead animals and other organic matter that falls to the bottom.

But the level of nutrients reaching the surface is expected to fall, which means there will be fewer of the tiny organisms that are the first link in the ocean food chain. With less organic material at shallower depths, there’s less to fall to the bottom. For some regions, the amount of material reaching the bottom is expected to go down by as much as half -- creating deep trouble for anything that lives in the deep ocean.