Alanna Mitchell will take us on a dive 3,000 feet into a far Tortuga sinkhole where no one has gone before to discover new life forms, new chemical compounds, and new insights into how it all comes together on the ocean planet. Alanna Mitchell is journalist who travels with ocean scientists and marine biologists to discover how we live with oceans and depend on marine life. With her clear-eyed immediacy she writes in the style of Rachel Carson, yet more personable. We care that carbonic acid is increasing in seawater with increasing carbon in the atmosphere. During the last century and a half of human activity ocean water acidity has increased by 30%. What does it mean for you and me when calcareous sea critters start to fizzle in rising seas? Alanna Mitchell shares her experiences with us and will read of her dive from her book, Seasick: Ocean Change and the Extinction of Life on Earth.