Earth's atmosphere in dynamic coupling envisaged through atmospheric tides and atmospheric gravity waves: A view on the past‐present‐future research

Abstract

In 1982–1985 an international scientific endeavor was attempted as the Middle Atmosphere Program, contributing successfully to exploring the last unknown part of the atmosphere on the planet Earth, the middle atmosphere. Now it seems timely for us to consider the whole atmosphere, which extends from the ground to the upper atmosphere and further into space as an entity. Each part of the atmosphere couples not only horizontally (globally) but also vertically. While the horizontal coupling is mainly important for conventional meteorology, the vertical one is significant, say, for space physics and, probably, future meteorology and will be the present topic. Atmospheric waves play an important role for the dynamic coupling of the atmosphere, transporting energy, momentum, and material mainly from below and releasing on the way in their propagation upward. Already in the last century, the existence of the tidal dynamo for the geomagnetic Sq variation in the upper atmosphere was known as a manifestation of the dynamic coupling by atmospheric tides. Atmospheric internal gravity waves are now found to play an important role, among many others, in the general circulation of the middle atmosphere which is another manifestation of the dynamic coupling of the atmosphere. Reviewing remarkable progress in the last 40 years in the research of this subject, the author has suggested that frontiers of the future research would be to develop a GCM (General Circulation Model) to include the upper atmosphere and to establish an equatorial atmosphere observation system.