Earth Science

Earth science (also known as the Earth Sciences, geoscience, or the geosciences) is an umbrella term for the sciences related to the planet Earth. The main disciplines within Earth science include geology, geodesy, geophysics, soil science, oceanography, hydrology, glaciology, and atmospheric sciences. These disciplines are oriented toward studying the various areas or "spheres" of the Earth system, such as the atmosphere, hydrosphere, lithosphere, and biosphere.

Earth science is arguably a special case in planetary science, being the only known life-bearing planet. Given the numerous interactions between the Earth's spheres, many modern fields of earth science are formed with interdisciplinary approaches.

Earth's Spheres

 * Geology - This discipline is devoted to the study of the rocky parts of the Earth's crust (or lithosphere) and its historic development. Major subdisciplines are mineralogy and petrology, geochemistry, geomorphology, paleontology, stratigraphy, engineering geology, and sedimentology.
 * Geodesy and Geophysics -  Joined together in the International Union of Geodesy and Geophysics (IUGG), these disciplines investigate the figure (size and shape) of the Earth, its reaction to forces, and its potential fields, such as the magnetic and gravitational fields. Geophysicists also explore the Earth's core and mantle and the natural deposits, while geodesists study the movement of stars and satellites.
 * Soil Science - It involves studying the outermost layer of the Earth's crust that is subject to soil formation processes. This layer is known as the pedosphere. Major subdisciplines include edaphology (the study of the influence of soils on living things) and pedology (the study of soil formation, structure, and classification).
 * Oceanography and Hydrology (including Limnology) - They encompass studying the marine and freshwater domains of the Earth, which make up the hydrosphere. Major subdisciplines include hydrogeology and physical, chemical, and biological oceanography. Within the scientific union IUGG, these disciplines (except the chemical ones) are joined with geophysics.
 * Glaciology - It covers the icy parts of the Earth, also known as the cryosphere.