From bow waves to traveling atmospheric disturbances: Thermospheric perturbations along solar eclipse trajectory

Simulations show that temperature and horizontal wind perturbations have different wave rears but similar wavefronts, due to the coupling of energetic and dynamic processes. The perturbations are closely related to the eclipse trajectory, and their phase speed is modulated by the eclipse speed.

As the eclipse shadow sweeps through the upper atmosphere, traveling atmospheric disturbances (TADs) are launched in the eclipse region and they, moving along with their moon shadow source, form bow wavefronts of thermospheric disturbances. The perturbations at a particular time are superimposed by preexisting waves and newly excited waves. With the termination of the eclipse near the sunset terminator, individual sequences are not any more organized along a specific alignment to form a bow wave.