The Ends of the World: Volcanic Apocalypses, Lethal Oceans, and Our Quest to Understand Earth's Past Mass Extinctions

by Peter Brannen

To understand what happened in the oceans at the end of the Triassic, it’s useful to look at modern coral reef systems, which have shrunk by perhaps 30 percent since the early 1980s (an appalling, geologically instantaneous lightning strike). Coral growth rates have slowed by 20 percent in the past two decades, and devastating bleaching events—what happens when warmer water forces corals to lose the microorganisms upon which they rely for food—have become common. Humans are currently increasing the carbon dioxide concentration in the atmosphere at a rate of 2 parts per million every year; if this trend continues and the oceans continue to acidify, coral reefs worldwide “will become rapidly eroding rubble banks” by midcentury, according to one landmark study. Reef diving after the End-Triassic mass extinction would bring a snorkeler back to this future, face-to-face with a world of broken slimy husks of coral that once billowed with Technicolor clouds of life.