|
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 |
 |
 |
 |
|
|
Upper Troposphere |
Negligible |
|
Zero |
|
|
Middle Troposphere |
|
|
Negligible |
Zero |
|
Surface |
|
Negligible |
Zero |
|
Gray Areas Indicate Terms that
Are Large
|
DISCUSSION:
Upper Tropospheric Constraints
Wind flows through trough and ridge patterns or (V – c) >>> 0
Implications: Air moves through divergent areas east of trough axes and west of downstream ridge axes. The divergence decreases the absolute vorticity of these air parcels to such an extent that the vorticity advection term is nearly cancelled.
In the upper troposphere, areas of divergence coincide with areas of cyclonic vorticity advection. |
 |
|
Middle Tropospheric Constraints
Roughly approximates Level of Non-Divergence
Implications: Absolute Vortticity is conserved.
In the middle troposphere, along trajectories (and, in certain restrictive circumstances, streamlines), absolute vorticity is conserved.
|
 |
|
Lower Tropospheric Constraints
Pressure/Height patterns tend to be concentric
Implications: Increases in absolute vorticity (development) are associated with convergence. |
 |
