Slide 17 of 29
Notes:
Vertical cross section of ageostrophic circulation/vertical motion (yellow arrows), wind divergence (blue) and wind convergence (red).
As it was to be expected, the low level convergence and upper divergence east of the trough axis favors ascending vertical motion…as indicated by the vectors/arrows pointing up. West of the trough, the mid level convergence and low level divergence favors downward (subsidence) vertical motion… once again depicted by the vectors/arrows pointing towards the surface.