Towards a Lagrangian-mean description of stratospheric circulations and chemical transports

Abstract

The theory of Lagrangian means and Stokes drifts is reviewed, with particular attention to recent developments and to possibilities for applying the ideas to the stratosphere. The properties of Lagrangian means for finite-amplitude disturbances in spherical geometry pose certain conceptual and technical problems, which appear unavoidable if the notion of Lagrangian mean is to be defined in an exact, coordinate- independent manner compatible with Stokes’s classical theory.