La atmosphere can be divided into a certain number of horizontal layers supported by different variables, such as pressure, temperature, density, chemical composition, electrical and magnetic molecular state. With each of them it is possible to try to match a section in altitude and, in the most favorable cases, a structure model. However, since there are still regions of the atmosphere that are being investigated and the studies of the upper layers are quite recent, there are no universally accepted definitions for the different levels.
Una synthetic vision of the set allows these differentiations to be made, from the ground to the outside we would have:
1. Homosphere. Up to an altitude that is conventionally reached 80 km is this first layer, where the chemical composition is uniform, the laws of the perfect gases are fulfilled in it, and in its physical structure the altitudinal distribution of densities, pressures and temperatures is basic.
2. Heterosphere. In contrast to the previous zone, the regions located above lose uniformity in their chemical composition, the general laws of hydrostatics are no longer met and the layered arrangement is identified by its composition rather than by its physical characteristics; thus, we speak of the layer of molecular nitrogen (up to 200 km altitude), from atomic oxygen (located between 200 and 1.000 km), of Helium (between 1.000 and 3.500 km), etc. At the same time, due to the absence of turbulent mixing of the gaseous mass, diffusion separation occurs and the heavier gases accumulate downwards, while the lighter gases tend to concentrate at higher levels where they can escape the Earth's gravitational field.
Image: Riconsolidario