| Summary of Vorticity Equation Terms |
| Term | Peak Magnitude (units: 10-10 s-2) Carlson: text,table 3.1 & Grotjahn (1996) | Vertical Distribution | Horizontal Distribution | Comments |
| Horizontal Advection | 30, 50 & 50 | increases w/ height as does wind | dipole w/ pos. ahead and neg. behind a low. Opposite for a high. Must be zero at vort. max/min for rotational wind. | Rotational wind part is largest: 80-90% of total beta*v planetary vort. advect. is small but widespread. Div. wind advect small |
| Vertical Advection | 5, 5 & 7 | max is in mid troposphere roughly where omega a max | dipole pattern similar to horiz. advection | leading part of dipole larger => growth. Mixes fD changes to alter vort. at D=0 level |
| Divergence | 14, 15 & 30 | max in upper and max in lower troposphere | dipole pattern: "moves lower trof ahead," pulls upper trough back. Leading pole > trailing pole => growth. | by opposing advection above and reinforcing advection below this term tries to maintain the tilt upstream fD > zeta D for weak lows. Latent heating probably similar. |
| Tilting | 7, 10 & 15 | peak values in mid troposphere | Extrema imply shrinking merid. extent while ampl. and stretching zonal extent. Trough pulled east. Vort. tendency <0 on cold side of sfc. fronts. Tendency >0 near sfc low. | Often stated as being important term for fronts, jets and mesoscale features. Locally large but small in extent, like VA term may mix fD changes @ other levels to alter vort. in mid troposph. |
| friction | 3, 5 & ___ | peak values near sfc. | slows down winds so pattern matches vort. Vort. tendency <0 for zeta >0 & vice-versa | analysis in Carlson does not include indirect contrib. to D for x-isobar flow & hence friction contributes to div. term. |
Table copyright R. Grotjahn 1998.
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