Many of today's most renowned explorers are oceanographers. National Geographic Explorer-in-Residence Sylvia Earle, posing in a submersible on the docks of Monterey, California, is nicknamed "Her Deepness." Earle has logged in more than 7,000 hours underwater, and was instrumental in having Google Earth display ocean data.

Photograph by James A. Sugar, National Geographic
  • Sylvia is an oceanographer, scuba diver, and research scientist. She founded Mission Blue, an organization dedicated to protecting the ocean from threats such as climate change, pollution, habitat destruction, invasive species, and the dramatic decrease in ocean fish stocks.


    Sylvia’s interest in the ocean sprang from her love of animals. Growing up in New Jersey, she remembers “I was always interested in critters, and most of them were in the ocean!”

    Sylvia studied oceanography and biology at Florida State University, before earning her PhD in phycology (the study of algae) from Duke University.


    “You never know what you’re going to find! Ninety-five percent of the ocean is not explored.”


    “Never having enough time. I can never imagine being bored; there’s just so much to explore and not enough time to do it.”


    “The science of everything. Geography is the entire planet, and what it holds.”


    Sylvia has dived in all five of the world’s oceans, and plays a leading role in establishing marine protected areas (MPAs) as “hope spots” around the world. MPAs are intended to “protect and restore the blue heart of the planet,” Sylvia says.

    The next place Sylvia will dive is the Sargasso Sea, near Bermuda in the Atlantic Ocean. She is working with the High Seas Alliance to establish an MPA there. Like many groups Sylvia works with, the High Seas Alliance is a diverse group of environmentalists, fishermen, and commercial businesses. Sylvia hopes the alliance “will encourage the Bermudan government to protect a small area, and for that to be a springboard for protection of a larger area of the Sargasso Sea.”

    Protecting the ocean really protects ourselves, Sylvia says. “We are all sea creatures. We all depend on the ocean.”

    Pointing out the oxygen and other atmospheric gases released by the ocean, Sylvia laughs, “If you like to breathe, you better like the ocean!”


    Oceanography is a broad discipline with many sub-disciplines. “Whether you’re interested in air, the history of the planet, currents, microbes, or whales, there’s plenty to do!” Sylvia says.


    “Everyone should be literate about the ocean,” Sylvia says. “No child should be left dry!”

    Oceanographer Sylvia Earle

  • Term Part of Speech Definition Encyclopedic Entry
    air Noun

    layer of gases surrounding Earth.

    Encyclopedic Entry: air
    biology Noun

    study of living things.

    climate change Noun

    gradual changes in all the interconnected weather elements on our planet.

    Encyclopedic Entry: Earth's Changing Climate
    commercial Adjective

    having to do with the buying and selling of goods and services.

    current Noun

    steady, predictable flow of fluid within a larger body of that fluid.

    Encyclopedic Entry: current
    diverse Adjective

    varied or having many different types.

    encourage Verb

    to inspire or support a person or idea.

    environmentalist Noun

    person who studies or works to protect the Earth's ecosystems.

    establish Verb

    to form or officially organize.

    fish stock Noun

    amount of fish available to be harvested in a specific area at a specific time.

    gas Noun

    state of matter with no fixed shape that will fill any container uniformly. Gas molecules are in constant, random motion.

    geography Noun

    study of places and the relationships between people and their environments.

    Encyclopedic Entry: geography
    government Noun

    system or order of a nation, state, or other political unit.

    habitat Noun

    environment where an organism lives throughout the year or for shorter periods of time.

    Encyclopedic Entry: habitat
    invasive species Noun

    type of plant or animal that is not indigenous to a particular area and causes economic or environmental harm.

    Encyclopedic Entry: invasive species
    marine protected area (MPA) Noun

    area of the ocean where a government has placed limits on human activity.

    microbe Noun

    tiny organism, usually a bacterium.

    Mission Blue Noun

    nonprofit organization whose mission is to "raise public awareness and move people to help protect this vital natural resource."

    ocean Noun

    large body of salt water that covers most of the Earth.

    Encyclopedic Entry: ocean
    oceanographer Noun

    person who studies the ocean.

    oxygen Noun

    chemical element with the symbol O, whose gas form is 21% of the Earth's atmosphere.

    PhD Noun

    (doctor of philosophy) highest degree offered by most graduate schools.

    planet Noun

    large, spherical celestial body that regularly rotates around a star.

    Encyclopedic Entry: planet
    pollution Noun

    introduction of harmful materials into the environment.

    Encyclopedic Entry: pollution
    research scientist Noun

    person who studies and tries to discover facts about a specific problem, question, or field of learning.

    Sargasso Sea Noun

    area of the Atlantic Ocean, between the Caribbean Sea and the Azores.

    scuba noun, adjective

    (self-contained underwater breathing apparatus) portable device for breathing underwater.