Scaling of Eliassen-Palm flux vectors

Abstract

Eliassen-Palm flux is one of the main diagnostics tools for wave propagation and wave-mean flow interaction in atmospheric dynamics and in particular stratosphere-troposphere coupling. Even though the theory has been derived in the 1960s, there is still no consensus about how to display the flux vectors in a plot. This is particularly true where both the troposphere and stratosphere are of importance. Some of the traditional methods are to scale the arrows by either pressure, the exponential of height, the square root of pressure, or even by an arbitrary factor. But the arguments for any of those methods are subjective, and they result in both different amplitudes and direction. Here, we propose an objective way of scaling EP flux vectors, in either linear or logarithmic pressure or height coordinates, which allows for a physically sound representation throughout the entire atmosphere.