Mesospheric

Mesospheric refers to the mesosphere, the atmospheric layer between the stratosphere and the thermosphere. The mesosphere extends roughly from 50 to 85 kilometers above the Earth's surface, and the term is used to describe processes, phenomena, or measurements associated with this region.

Temperature in the mesospheric zone generally decreases with altitude, making it the coldest layer of the atmosphere. Near the upper boundary, temperatures can fall to around -90°C. By contrast, the layers below and above have warmer temperatures, and the mesopause marks the upper limit of the mesosphere at about 85–90 kilometers.

The mesospheric environment is shaped by strong wind systems and gravity waves traveling from lower layers, which drive significant vertical mixing and contribute to its dynamic character. It is also the site where most meteoroids burn up upon entry, leaving behind metal vapors that form atmospheric metal layers detected by researchers.

Notable mesospheric phenomena include noctilucent, or night-shining, clouds that form near the mesopause during polar summers, and pronounced airglow from chemical reactions, particularly in hydroxyl and molecular oxygen emissions. These emissions provide valuable diagnostics of mesospheric chemistry and dynamics.

Chemically, the mesosphere is dominated by diatomic nitrogen and oxygen, with trace species such as atomic oxygen, ozone, hydroxyl, and meteoric metal atoms. Photochemical reactions driven by solar radiation shape its composition and seasonal variations.

Observational methods include ground-based lidars and radars, airglow imaging, rocket and satellite measurements, and spectroscopic analyses, all used to study temperature, winds, composition, and light emissions in this elusive atmospheric layer.