I have the following equation for the shearing term of the deformation zone in meteorology. The reference is this link: http://www.zamg.ac.at/docu/Manual/SatManu/main.htm?/docu/Manual/SatManu/CMs/Def/backgr.htm
Shearing = dV/dx + dU/dy
U and V are the zonal and meridional winds, respectively. X and Y are the longitude and latitude,respectively.
I would like to know what does it mean to have if:
a). dV/dx < 0 (dU/dy > 0)
b). dU/dy < 0 (dV/dx > 0)
c). both dV/dy and dU/dx are less than 0.
d). both dV/dy and DU/dx are greater than 0
I'll appreciate any help.