Earth science

[1] This is a branch of science dealing with the physical, chemical, and biological complex constitutions and synergistic linkages of Earth's four spheres: the biosphere, hydrosphere/cryosphere, atmosphere, and geosphere (or lithosphere).

It includes the physical characteristics and processes that occur in the lithosphere as well as how they are affected by geothermal energy.

[4] Plate tectonics, mountain ranges, volcanoes, and earthquakes are geological phenomena that can be explained in terms of physical and chemical processes in the Earth's crust.

[6] Beneath the Earth's crust lies the mantle which is heated by the radioactive decay of heavy elements.

As the result of seafloor spreading, new crust and lithosphere is created by the flow of magma from the mantle to the near surface, through fissures, where it cools and solidifies.

Atmospheric chemistry was developed in the 20th century to measure air pollution and expanded in the 1970s in response to acid rain.

In all, the atmosphere is made up of about 78.0% nitrogen, 20.9% oxygen, and 0.92% argon, and small amounts of other gases including CO2 and water vapor.

[15] Water vapor and CO2 cause the Earth's atmosphere to catch and hold the Sun's energy through the greenhouse effect.

In addition to trapping heat, the atmosphere also protects living organisms by shielding the Earth's surface from cosmic rays.

[17] The magnetic field—created by the internal motions of the core—produces the magnetosphere which protects Earth's atmosphere from the solar wind.

Applied hydrology involves engineering to maintain aquatic environments and distribute water supplies.

Applied hydrogeology seeks to prevent contamination of groundwater and mineral springs and make it available as drinking water.

The earliest exploitation of groundwater resources dates back to 3000 BC, and hydrogeology as a science was developed by hydrologists beginning in the 17th century.

It considers how living things use resources such as oxygen, water, and nutrients from the Earth to sustain themselves.

A foundational idea in Earth science is the notion of uniformitarianism, which states that "ancient geologic features are interpreted by understanding active processes that are readily observed."

The rocky side of a mountain creek in Costa Rica
Layers of sedimentary rock in Makhtesh Ramon
A volcanic eruption is the release of stored energy from below Earth's surface. [ 5 ]
The magnetosphere shields the surface of Earth from the charged particles of the solar wind .
( image not to scale. )
Computer simulation of Earth 's field in a period of normal polarity between reversals. [ 21 ] The lines represent magnetic field lines, blue when the field points towards the center and yellow when away. The rotation axis of Earth is centered and vertical. The dense clusters of lines are within Earth's core. [ 22 ]
Movement of water through the water cycle