On a Graphical Method for an Approximate Determination of the Vertical Velocity in the Mid-Troposphere

A simple graphical method for determining the vertical velocity from a simplified, but consistent form of a diagnostic equation for this quantity is developed. It is shown that the main term in the equation is the advection of temperature in the vorticity field. Section 2 contains simple rules from which the sign of the vertical velocity may be determined.

An approximate solution to the equation is found in section 3, while section 4 contains an investigation of the accuracy of this solution as function of the scale of the motion. Different types of approximate solutions are investigated.

Section 5 contains an example of the use of the method.