Atmosphere of earth
Atmosphere of Earth
The Atmosphere of Earth (pronounced: /ætˈmɒsfɪər ɒv ɜːrθ/) is a layer of gases, commonly known as air, that surrounds the planet Earth and is retained by Earth's gravity. The atmosphere of Earth protects life on Earth by creating pressure allowing for liquid water to exist on the Earth's surface, absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation).
Etymology
The term "atmosphere" is derived from the ancient Greek words "ἀτμός" (atmos), meaning "vapor", and "σφαῖρα" (sphaira), meaning "sphere". The term "Earth" is from the Old English "eorþe", which could mean "ground", "soil", "dry land", "country", "territory", "region", or "world".
Composition
The atmosphere of Earth is composed of nitrogen (about 78%), oxygen (about 21%), argon (about 0.9%) with carbon dioxide and other gases making up the remaining 0.1%. Trace amounts of other gases are also present, including neon, helium, methane, krypton, and hydrogen.
Layers
The atmosphere of Earth can be divided into five main layers. These are the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. Each layer has different characteristics, including variations in temperature, pressure, and the types of gases present.
Related Terms
- Greenhouse effect: The process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without this atmosphere.
- Ozone layer: A region of Earth's stratosphere that contains a high concentration of ozone (O3) molecules.
- Air pressure: The force exerted onto a surface by the weight of the air above it in the atmosphere of Earth.
- Climate: The long-term pattern of weather in a particular area.
This WikiMD.org article is a stub. You can help make it a full article.