An Earth Science department is a field of physical science research at universities that involves four distinct areas of study: geology, meteorology, oceanography, and astronomy. While the Earth sciences are generally thought to deal with the structure and activity of either land or oceans on Earth, an Earth Science department may also focus its research entirely on geological activity on other planets in the Solar System, as well as minor bodies like moons, asteroids, and comets. Many sub-divisions of each of the major Earth science fields also exist, such as environmental geology and hydrogeology in the field of geology. An education in the Earth sciences has a wide array of applications, though common uses for the degree include in oil and mineral prospecting, environmental services and research, as well as government administration and protection of natural regions.
Studying in an Earth science department to obtain a general degree in geology is usually just the first step towards making use of such education. Earth sciences majors with bachelor's degrees may find employment in the environmental or government arena, but most geoscience research requires at least a graduate degree to work in commercial fields. Careers based on an Earth science department education for jobs in the petroleum field, for instance, often require a master's degree or PhD level of training. Specialization also becomes increasingly important for fields like environmental geology, that can employ people with geology degrees that have gone on to further training in fields like hydrogeology or conservation biology.
The study of oceanography is an increasingly diverse field that is based out of the Earth science department as well. Current specialties in oceanography as of 2011 include physical oceanology that studies salinity, wave, and current features of oceans, and environmental chemistry that looks at chemical changes through natural means or by human pollution. Oceanology, in general, is another related field that studies all the oceans on the Earth as a whole and marine geology deals exclusively with the study of the ocean floor and tectonic activity.
Of broader importance to other industrial and commercial interests is the Earth science department promotion of meteorology. Meteorology deals not just with local weather conditions, but also with long-term aspects of the weather in climatology, and changes in weather patterns caused by human and natural effects researched through atmospheric chemistry. Geochemistry can also have effects on meteorology, where the composition of the Earth is looked at in terms of how it has indirect effects on climate.
Research into geology on other orbiting bodies in the Solar System becomes an increasingly important field in the Earth science department as of 2011, since more detailed analysis of extraterrestrial bodies are increasingly being conducted by multiple nations. These fields of specialization include planetary science that looks at the processes that formed the planets, astronomy for the general observation of space, and astrophysics that deals with the physical properties and movement of bodies in space such as the tidal effects the Moon has on the surface of the Earth's oceans.