QG theory part 3 vorticity Flashcards
It can be shown that the rate of change of vorticity is strongly dominated by two processes
(change of vorticity with time)
- Vorticity advection
- Divergence
vorticity advection is resembled by
Divergence is resembled by
Vorticity
Rotation of wind around vertical axis (cyclonic or anticyclonic) vertical or in a slope
storm has …………. vorticity
large
How to get vorticity equation?
- using horizontal component of momentum equation (zonal and meridional)
- take the derivative of y of u component (zonal)
- take the derivative of x of v component (meridional)
- rearange
- subtract (meridional-zonal)
- simplify by scale analysis
vorticity equation:
term A means
local term
term b means
Vorticity advection
term c means
constant (coriolis parameter) & divergence
what does the equation mean?
vorticity is changing due to vorticity advection and divergence
the divergence term describe
the effects of divergence on the change of vorticity within a fluid.
When divergence occurs in a fluid, vorticity becomes more …………………
anticyclonic
When…………………… occurs in a fluid, vorticity becomes more anticyclonic
divergence
When convergence occurs in a fluid, vorticity becomes more ……………..
cyclonic
When ………………………..occurs in a fluid, vorticity becomes more cyclonic
convergence
When divergence occurs in a fluid, vorticity becomes more anticyclonic. Thus, …………………………spins up …………………………..vorticity
convergence, cyclonic
When ………………….occurs in a fluid, vorticity becomes more ……………………. Thus, convergence spins up cyclonic vorticity
divergence, anticyclonic
Surface low-pressure centers are characterized by ………………………….and thus tend to be foci for the production of low-level cyclonic vorticity.
convergence
Surface low-pressure centers are characterized by convergence and thus tend to be ……………………………………………………..
foci for the production of low-level cyclonic vorticity.
upper divergence results in vorticity….
anticyclonic
upper convergence results in……
cyclonic
vorticity cyclonic (+ve or -ve)
+ve vorticity
vorticity anticyclonic (+ve or -ve)
-ve vorticity
Upstream of the trough, the geostrophic wind is directed from the ……………………………towards the ……………………………
vorticity minimum, vorticity maximum
………………………………………., the geostrophic wind is directed from the vorticity minimum towards the vorticity maximum.
Upstream of the trough
Downstream of the trough, the geostrophic wind is directed from the …………………………………. towards the ……………………………
vorticity maximum, vorticity minimum
…………………………………………, the geostrophic wind is directed from the vorticity maximum towards the vorticity minimum.
Downstream of the trough,
Note that regions of maximum vorticity advection is collocated with regions of …………………………………….
divergence
Note that regions of …………………………………vorticity advection is collocated with regions of divergence
maximum
Term A
Vorticity minimum in the ridges
Term B
Min. vorticity advection
Term C
Maximum vorticity advection
Term D
Vorticity max in the trough
The most important application of QG theory is
the diagnosis of vertical motion
The fundamental equation of QG theory indicate that ………………….and ……………………………………are dynamically forced by two mechanisms:
–Vorticity advection
–Thermal advection
vertical motion 𝜔, geopotential height tendency 𝜒
The fundamental equation of QG theory indicate that vertical motion 𝜔 and geopotential height tendency 𝜒 are dynamically forced by two mechanisms:
- Vorticity advection
- Thermal advection
