“Bomb Carbon” Has Been Found in Deep-Ocean Creatures
August 12th, 2020Via: Scientific American:
Until now, it has been unclear whether bomb carbon has managed to spread into the farthest crevices of the world, especially the deepest seas. It would have taken natural oceanic circulation about 1,000 years to carry it to the depths of the Mariana Trench. And in fact, testing for the new study showed that the waters of the trench did have low levels of carbon-14—which is what the researchers expected, given the long travel time from atmosphere to deep ocean.
But when they used traps to catch and test crustaceans living at these depths, they detected much higher levels of the isotope in these animals’ tissues and gut contents than in the surrounding waters. The bomb carbon had to be arriving another way that brought it there faster, and the researchers surmised it was taking a shortcut via the food chain. Organic matter—including the poop and carcasses of surface-dwelling life—falls through the water column in just weeks or months. When crustaceans on the seabed munch these morsels, they absorb the signature of nuclear tests into their bodies, the researchers say in their study, published online in April in Geophysical Research Letters.
