Marine careers encompass a wide range of fields, from marine biology to oceanography to marine veterinary medicine, marine mammal trainers and beyond. Most people who thrive in these career fields have a love and passion for the ocean and aquatic life of all types.

The field of oceanography actually encompasses several sub-fields: physical oceanography, marine geology and geophysics, physical oceanography, and marine chemistry and geochemistry.

Although these are actually separate career fields, they are also closely-related and to some extent interdependent. Oceanographers of all types often work closely together to decipher the riddles and mysteries of our oceans. Oceans cover 70% of the Earth's surface, after all, and much of what happens beneath the surface of these waters is less known to us than the depths of outer space.

Knowledge of the Earth's oceans will become more important in the coming years and decades. An ever-growing global population will stress the resources of our planet in many ways, including the production of food, water, oil, and marine habitats. The oceans will be asked to provide much of these resources, and thus oceanographers of all types will be needed to keep pace with new demands and new technologies.

In the field of marine biology, which is essentially the study of organisms that inhabit the oceans, researchers study the behaviors and interactions of these organisms in great detail. Much of this research is field work done on location in the oceans themselves, while other laboratory work is performed in land-based labs and research centers.

Marine geology is another interesting field to explore. Geological oceanographers study the formations, composition, and history of the seafloor. Mountains, valleys, islands, canyons, and other geological features are as common beneath the ocean's surface as they are on dry land. These oceanographers use sonar and remotely-operated vehicles to study and explore these underwater geological features.

Other marine careers include ocean engineering, underwater filmmaking, marine education, marine mammal training, commercial diving, aquarium and ocean park jobs, and more.

Almost all marine careers require at least a bachelor's degree in the field of oceanography, marine biology or marine science. These degree programs are usually heavy in biology, physics, chemistry and geology, so these are courses to focus on if your undergraduate or still in high school.

In terms of finding out which colleges are the “best,” for the marine career fields, U.S. News and World Report does an annual ranking. They consider such factors as the quality of the faculty and the academic programs themselves. This would be a good place to start, along with checking the Internet and career counselors in your area.