atmosphere
Atmosphere refers to the layer of gases surrounding a celestial body, such as the Earth. On Earth, the atmosphere is composed primarily of nitrogen (78%) and oxygen (21%), with traces of other gases such as carbon dioxide, water vapor, and noble gases.
The atmosphere plays a crucial role in supporting life on Earth. It provides a protective shield against harmful solar radiation, regulates the planet's temperature by trapping heat, and is involved in various weather phenomena. It also contains the oxygen necessary for respiration and carbon dioxide for photosynthesis, thus sustaining the biosphere.
The atmosphere is divided into several layers based on temperature and composition. The lowest layer is the troposphere, where weather occurs and living organisms exist. Above the troposphere is the stratosphere, which contains the ozone layer and helps absorb harmful ultraviolet radiation. The higher layers, such as the mesosphere, thermosphere, and exosphere, gradually transition into space.
Changes in the composition and structure of the atmosphere can have significant impacts, such as climate change due to increased greenhouse gas emissions or depletion of the ozone layer due to human-made chemicals. Understanding and preserving the atmosphere is crucial for maintaining a habitable environment on Earth.