Speaker
Description
Mesospheric bores are non-linear solitary type internal waves observed in the 80 – 100 km region of Earth atmosphere, the upper mesosphere. The existence of these waves is known for more than two decades. Researchers have attained a reasonable understanding on the nature of such waves. However, some of the observed characteristics of these waves cannot be explained based on existing knowledge. Mesospheric bores were initially thought to be very rare events, but recent investigations indicate that such events are relatively frequent. These waves have potential to contribute considerably to the energy and momentum deposition within the mesosphere since they propagate long horizontal distances and are associated with large amplitude gravity waves. Moreover, their effects on the surrounding atmosphere are not understood. Recent results show that they play a role in altering the concentrations of minor species in the upper mesosphere within short time scales. We would like to provide a brief overview of our current understanding of the mesospheric bores, highlight the recent observations of their effects on the sodium layer and the noctilucent clouds with emphasis on observations from the Northern Scandinavia, and also discuss the challenges in the observational studies of the mesospheric bores.
