cover image At Every Depth: Our Growing Knowledge of the Changing Oceans

At Every Depth: Our Growing Knowledge of the Changing Oceans

Tessa Hill and Eric Simons. Columbia Univ, $32.95 (280p) ISBN 978-0-231-19970-4

In this unsettling study, Hill, an oceanographer at the University of California Davis, and science writer Simons (Darwin Slept Here) explore ocean ecosystems and how global warming and pollution are affecting them. Explaining how kelp forests, tide pools, and other aquatic environments function, the authors note that coral reefs form from the symbiotic relationship between dinoflagellate algae, which live inside of coral and feed on its “waste nutrients,” and coral itself, which “builds a skeleton out of calcium carbonate,” resulting in “the beautiful structure[s] people are familiar with” that provide shelter to countless fish and other organisms. Underscoring the threat posed by climate change, Hill and Simons report that amphipods (a kind of tiny crustacean) collected from the Mariana Trench were found to be “laden with human-produced polychlorinated biphenyls, chemicals [that have been] banned for decades,” suggesting even the most remote places on Earth aren’t safe from humans. The authors outline pollution’s toll on the natural world in haunting detail (“In albatross breeding colonies across the Pacific, the large ocean-roaming birds die with stomachs full of plastic, their bodies decomposing until all that remains is a neatly arranged pile of human junk”), providing an incisive look at a world in crisis. This troubling assessment of how humans are devastating the world’s oceans hits home. Illus. (Feb.)