'The ocean is in trouble'

Earle stays in a submarine during an expedition for Mission Blue, a conservation innitiative she launched in 2009.

At a glance: Sylvia Earle

For Sylvia Earle, it all began in 1953 when she first tried scuba diving. In 1964 the PhD of Duke University embarked on her first groundbreaking expedition: a six-week Indian Ocean voyage. She was the only woman on the crew of 71.

In 1970 she led a team of all-female aquanauts on the mission, Tektite II. After spending two weeks underwater, the longest uninterrupted time scientists had ever been submerged, the team resurfaced as celebrities.

Earle has since led more than 100 explorations, including a world record-setting dive in 1979, when she walked on the Pacific Ocean floor while using a personal submersible called the Jim Suit-the lowest depth ever to be explored by foot.

Since then, she has used about 30 kinds of submarines and started three companies and a nonprofit foundation called Deep Search to design and build systems to access the deep sea.

In 2009, Earle founded the Sylvia Earle Alliance and its special initiative Mission Blue, with a vision to create a global network of marine protected areas.