- Rear-sloping warm air lift up along vertical suface of cold front boundary.
- Lighter precip. fills in behind and above the front.
- Forward-slping warm air lift parallel and ahead of cold front that is moving more rapid tan frontal zone.
- Precip. out ahead of cold front.
vector difference between observed wind and geostophic wind.
Ageostrophic Wind Term A
- Isallobaric wind due to local pressure changes.
- Flows from center of pressure rise to pressure fall.
Ageostrophic Wind Term B
- Horizontal advective ageostrophic wind
- Inertial advetice(like wind advecting itself)
- Function of gradient wind balance and diffluence/confluence.
- Strongest where there are changes in the wind speed and or direction downstream
- "points" upstream (downstream) in cyclonically(anticyclonically)curved flow.
- "points" to the left (right) of the flow (in the NH) if the speeds increase (decrease) downstream.
- Tends to be most significant in the mid-upper troposphere where the wind is strongest and the wind speed changes are the most dramatic.
Ageostrophic Wind Term C
- Verical advective ageostrophic wind
- Inertial convective(diabatic)
- Strongest in regions of strong vertical wind shear and diabatic heating
- Rising parcels will accelerate in regions of strong shear
Ageostrophic Wind Term D
- Stongest in regions of strong vertical wind shear and diabatic heating
- Rising parcels will accelerate in regions of strong shear.
Ageostrophic Wind Term D
Ageostrophic Wind due to friction withing the PBL
- An 'intense', narrow, quasi horizontal current of wind that is associated with strong vertical wind shear, found at or near the tropopause
- at least 60kt UL and 30kt LL
- narrow: flow current width is 1/2 to 1 order of magnitude less than its length
- Isotach maximum embedded within jet steams
- Propogates through the jet steam.
- Upper boundary between troposphere and stratosphere.
- Upper boundary between positive lapse rate in troposphere and negative lapse rate in stratosphere.
- Upper boundary between relatively low ozone concetration in troposhere and relatively high ozone concentration in stratoshpere.
- also relatively high water vapor in trop. and relativly low water vapor in strat.
potential vorticity, since PV is related to absolute vorticity and static stability.
Isentropic Potential Vorticity
- Absolute voricity a fluid column would have if it were brought to some reference depth, enclosed between two isentropic(potential temperature) surfaces.
- A conservative quanitiy.
- Product of isentropic absolute vorticity and static stability.
- Min in tropopause height
- Max in tropopause pressure
- Min in geopotental
- Max in isentropic values
- Cyclonic circulation