A person who studies the ocean is called an oceanographer. Oceanography is a scientific discipline that encompasses all aspects of the Earth’s oceans and seas. This includes their physical and chemical properties, their origin and geologic framework and the life forms that inhabit the marine environment, according to Encyclopaedia Britannica.
Oceanography is divided into four separate, but related branches called physical oceanography, chemical oceanography, marine geology and marine ecology. Physical oceanography involves the properties of seawater, its movement and the interactions between the ocean waters and the atmosphere. Chemical oceanography involves the composition of seawater and the biogeochemical cycles that affect it. Marine geology involves the structure, features and evolution of the ocean basins. Marine ecology, which is also known as biological oceanography, is the study of sea plants and animals, including life cycles and food production.