Weather in the upper atmosphere

Aeronomy is the study of the upper atmosphere, its chemistry and the physical processes that govern it. Variations in the upper atmosphere affect numerous technologies upon which society relies, such as radio communications and GPS. These variations can be produced by events and changes in the Sun, or by weather effects from the lower atmosphere propagating upwards. The thermosphere is a layer of the upper atmosphere that extends from about 90 to 500 km. Embedded in it is the ionosphere, a region that contains a significant number of ions and free electrons, which affects the technologies mentioned before. Neutral winds in the thermosphere play an important role in the transport of momentum and energy in the upper atmosphere and affect the composition, dynamics and morphology of the ionospheric plasma. They present a highly dynamic behavior with changing geophysical conditions, time and location.

In this talk, I will give an overview of the study of the upper atmosphere, and I will present results regarding longitudinal and temporal variability of thermospheric zonal winds and their behavior during and after geomagnetic storms, obtained from satellite observations.