By Stokes' theorem, the integral of the normal component of this quantity over an area is equal to circulation around a loop, and it can also be defined as the curl of a velocity vector.
Both geostrophic advection and the convergence or divergence of a column of air are the only means of changing this quantity within a quasi-geostrophic atmosphere, according to a namesake equation, which along with the height, thermodynamic, and omega equations, defines QG theory. Stommel proposed that the absolute form of this quantity is conserved in ocean basins, accounting for the strength and narrowness of western boundary currents, while in the atmosphere, positive advection of this quantity is typically found downstream from troughs and is associated with rising motion. By Stokes' theorem, the integral of the normal component of this quantity over an area is equal to circulation around a loop, and it can also be defined as the curl of a velocity vector. For 10 points, name this quantity in fluid dynamics, a measure of rotation about an axis.
Both geostrophic advection and the convergence or divergence of a column of air are the only means of changing this quantity within a quasi-geostrophic atmosphere, according to a namesake equation, which along with the height, thermodynamic, and omega equations, defines QG theory.
{vorticity}