Atmosphere

The atmosphere is the gaseous envelope that surrounds the Earth and is held together by the planet's gravity. This envelope consists of various gases, whose proportions and properties change with altitude above the Earth's surface. The atmosphere plays a central role in supporting life on Earth by providing oxygen, regulating the climate, and protecting against harmful radiation.

The Earth's atmosphere is mainly composed of nitrogen (about 78%), oxygen (about 21%), and argon (about 0.93%), while trace gases like carbon dioxide and methane are present in smaller amounts. The mass of the atmosphere is approximately 5.15·10¹⁸ kg, which is less than one millionth of the Earth's mass.

The atmosphere is divided into several layers, including the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. These layers differ in temperature profiles and physical properties. Most weather phenomena occur in the troposphere, while the stratosphere contains the ozone layer, which filters harmful UV rays.

The functions of the atmosphere are diverse. It not only supplies oxygen for life but also regulates the climate through the greenhouse effect, protects against meteoroids, and enables communication via radio waves in the ionosphere. The transition to the upper atmosphere is gradual and ends in the exosphere, which merges into outer space. This complex gaseous envelope is both chemically diverse and dynamic and plays a crucial role in biological, climatic, and technological processes on Earth.