midlatitude cyclones - chapter 10kestrel.nmt.edu/~sessions/phys189/ab_ch10.pdf · cyclones phys 189...
TRANSCRIPT
![Page 1: Midlatitude Cyclones - Chapter 10kestrel.nmt.edu/~sessions/phys189/ab_ch10.pdf · Cyclones PHYS 189 Midlatitude Cyclone life cycle Rossby waves, vorticity, & cyclogenesis Surface](https://reader030.vdocuments.site/reader030/viewer/2022040414/5f1f7e76e7b0787db5286323/html5/thumbnails/1.jpg)
MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Relation of fronts in a midlatitude cyclone
PHYS 189 () Midlatitude Cyclones week 11 1 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Polar Front theory
Though cyclogenesis of mid-latitude cyclones do not alwaysoccur along the polar front, those that do can be describedby the Polar front theory
PHYS 189 () Midlatitude Cyclones week 11 2 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Clicker question
What type of front is shown in this diagram?A. warm
B. cold
C. stationary
D. occluded
PHYS 189 () Midlatitude Cyclones week 11 3 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Clicker question
What is the term for this stage in the life cycle of a midlatitudecyclone?
A. cyclogenesis
B. occlusion
C. maturity
D. senescence
PHYS 189 () Midlatitude Cyclones week 11 4 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Approaching maturity
Rotation from the initial kink in the stationary front creates aweak low pressure system which deepens. At this stage, thereare distinct warm and cold fronts.
I convergence occurs at the low pressure region
I convection along frontal boundaries create bands ofclouds
PHYS 189 () Midlatitude Cyclones week 11 5 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Mature midlatitude cycloneClicker question
In which area would over-running occur?
D
C
A
B
PHYS 189 () Midlatitude Cyclones week 11 6 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Mature midlatitude cycloneClicker question
What is the primarymechanism for uplift atA?
A. overrunning
B. convergence
C. localized instability
D
C
A
B
PHYS 189 () Midlatitude Cyclones week 11 7 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Mature midlatitude cycloneClicker question
Why are the cloud bandwidths so different at thewarm and cold fronts?
PHYS 189 () Midlatitude Cyclones week 11 8 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Clicker question
An occlusion representsA. cyclogenesis
B. cyclone intensification
C. gradual death of cyclone
D. none of the above
PHYS 189 () Midlatitude Cyclones week 11 9 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Midlatitude Cyclone life cycle
Looking for midlatitude cyclones
I current US weather
I Current European weather
I cartoon 1
I cartoon 2
I weather data &forecast
PHYS 189 () Midlatitude Cyclones week 11 10 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Rossby Waves
Rossby waves can generate anomalous temperatures in the mid-dle and high latitudes
PHYS 189 () Midlatitude Cyclones week 11 11 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Rossby wave
Rossby waves initiate rotation in the fluid.This rotation is called vorticity.
PHYS 189 () Midlatitude Cyclones week 11 12 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Rossby wave
Rossby waves initiate rotation in the fluid.
This rotation is called vorticity.
PHYS 189 () Midlatitude Cyclones week 11 12 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Rossby wave
Rossby waves initiate rotation in the fluid.This rotation is called vorticity.
PHYS 189 () Midlatitude Cyclones week 11 12 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity
vorticity: rotation in a fluid (ζ, zeta)
relative vorticity: vorticity relative to Earth’s surface
Earth vorticity: vorticity which depends on the rotation ofthe earth about it’s axis; depends on latitudeonly
absolute vorticity: sum of both relative and Earth vorticity =the overall rotation of the fluid
positive vorticity: counterclockwise in NH; clockwise in SH
negative vorticity: counterclockwise in SH; clockwise in NH
Vorticity is actually a vector (like angular momentum),whose direction points along the thumb of your right hand inNH; your fingers move in the direction of the fluid
PHYS 189 () Midlatitude Cyclones week 11 13 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity
vorticity: rotation in a fluid (ζ, zeta)
relative vorticity: vorticity relative to Earth’s surface
Earth vorticity: vorticity which depends on the rotation ofthe earth about it’s axis; depends on latitudeonly
absolute vorticity: sum of both relative and Earth vorticity =the overall rotation of the fluid
positive vorticity: counterclockwise in NH; clockwise in SH
negative vorticity: counterclockwise in SH; clockwise in NH
Vorticity is actually a vector (like angular momentum),whose direction points along the thumb of your right hand inNH; your fingers move in the direction of the fluid
PHYS 189 () Midlatitude Cyclones week 11 13 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity
vorticity: rotation in a fluid (ζ, zeta)
relative vorticity: vorticity relative to Earth’s surface
Earth vorticity: vorticity which depends on the rotation ofthe earth about it’s axis; depends on latitudeonly
absolute vorticity: sum of both relative and Earth vorticity =the overall rotation of the fluid
positive vorticity: counterclockwise in NH; clockwise in SH
negative vorticity: counterclockwise in SH; clockwise in NH
Vorticity is actually a vector (like angular momentum),whose direction points along the thumb of your right hand inNH; your fingers move in the direction of the fluid
PHYS 189 () Midlatitude Cyclones week 11 13 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
The value of the Earth vorticity at the equator is
A. maximum
B. zero
C. cannot be determined without more information
PHYS 189 () Midlatitude Cyclones week 11 14 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Clockwise rotation relative to the Earth’s surface in thesouthern hemisphere
A. partially cancels the Earth vorticity and decreases theabsolute vorticity
B. increases the absolute vorticity since it enhances fluidrotation in the same direction as the Earth vorticity
C. doesn’t give a notable difference to the absolutevorticity compared to counterclockwise rotation.
PHYS 189 () Midlatitude Cyclones week 11 15 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
The maximum in absolute vorticityA. occurs around the low pressure region
B. occurs around the high pressure region
C. is the same for both the high and low pressure regions
D. cannot be determined without more information
PHYS 189 () Midlatitude Cyclones week 11 16 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
The NH air shown in segment 1 hasA. positive relative vorticity
B. negative relative vorticity
C. zero relative vorticity
PHYS 189 () Midlatitude Cyclones week 11 17 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
The NH air shown in segment 2 hasA. positive relative vorticity
B. negative relative vorticity
C. zero relative vorticity
PHYS 189 () Midlatitude Cyclones week 11 18 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Recall angular momentum
angular momentum increases asthe can convergesvorticity works the same way:increases in vorticity correspondto converges; decreases give di-vergence
PHYS 189 () Midlatitude Cyclones week 11 19 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Recall angular momentum
angular momentum increases asthe can converges
vorticity works the same way:increases in vorticity correspondto converges; decreases give di-vergence
PHYS 189 () Midlatitude Cyclones week 11 19 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Recall angular momentum
angular momentum increases asthe can convergesvorticity works the same way:increases in vorticity correspondto converges; decreases give di-vergence
PHYS 189 () Midlatitude Cyclones week 11 19 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity and divergence
Changes in vorticity induce convergence/divergences:
−1
ζ
∆ζ
∆t= div
I div=divergence
I increases in vorticity (∆ζ > 0) give convergence
I decreases in vorticity (∆ζ < 0) give divergence
I What does div < 0 mean?
PHYS 189 () Midlatitude Cyclones week 11 20 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity and divergence
Changes in vorticity induce convergence/divergences:
−1
ζ
∆ζ
∆t= div
I div=divergence
I increases in vorticity (∆ζ > 0) give
convergence
I decreases in vorticity (∆ζ < 0) give divergence
I What does div < 0 mean?
PHYS 189 () Midlatitude Cyclones week 11 20 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity and divergence
Changes in vorticity induce convergence/divergences:
−1
ζ
∆ζ
∆t= div
I div=divergence
I increases in vorticity (∆ζ > 0) give convergence
I decreases in vorticity (∆ζ < 0) give
divergence
I What does div < 0 mean?
PHYS 189 () Midlatitude Cyclones week 11 20 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity and divergence
Changes in vorticity induce convergence/divergences:
−1
ζ
∆ζ
∆t= div
I div=divergence
I increases in vorticity (∆ζ > 0) give convergence
I decreases in vorticity (∆ζ < 0) give divergence
I What does div < 0 mean?
PHYS 189 () Midlatitude Cyclones week 11 20 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity and divergence
Changes in vorticity induce convergence/divergences:
−1
ζ
∆ζ
∆t= div
I div=divergence
I increases in vorticity (∆ζ > 0) give convergence
I decreases in vorticity (∆ζ < 0) give divergence
I What does div < 0 mean?
PHYS 189 () Midlatitude Cyclones week 11 20 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
How vorticity changes result in high and lowsurface pressures
Is this upper, lower, or middle troposphere?
Where can we expect convergence & divergence?
PHYS 189 () Midlatitude Cyclones week 11 21 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
How vorticity changes result in high and lowsurface pressures
Is this upper, lower, or middle troposphere?Where can we expect convergence & divergence?
PHYS 189 () Midlatitude Cyclones week 11 21 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
How vorticity changes result in high and lowsurface pressures
PHYS 189 () Midlatitude Cyclones week 11 22 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Surface low-pressure systems resulting from uppertropospheric motions are called
A. dynamic lows
B. cold core lows
C. thermal lows
D. warm core lows
E. A and B, OR C and D
PHYS 189 () Midlatitude Cyclones week 11 23 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Surface low-pressure systems resulting from localized heatingfrom below are called
A. dynamic lows
B. cold core lows
C. thermal lows
D. warm core lows
E. A and B, OR C and D
PHYS 189 () Midlatitude Cyclones week 11 24 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Which of the following structures corresponds to a warm coreand which is a cold core?
H
L L
L
warm cold
PHYS 189 () Midlatitude Cyclones week 11 25 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Which of the following structures corresponds to a warm coreand which is a cold core?
H
L L
L
warm cold
PHYS 189 () Midlatitude Cyclones week 11 25 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Absolute vorticity at 500 mb heights(mid-troposphere)
PHYS 189 () Midlatitude Cyclones week 11 26 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Relative vorticity can be induced by
A. curvature of the flow
B. shear
C. a change in Earth vorticity
D. all of the above
PHYS 189 () Midlatitude Cyclones week 11 27 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Vorticity
ζabsolute = ζEarth + ζrelative
PHYS 189 () Midlatitude Cyclones week 11 28 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Rossby waves, vorticity, & cyclogenesis
Clicker question
Which of the following statements is true?
A. Upper tropospheric air can influence surface weatherpatterns, but not vice-versa.
B. Surface weather patterns can influence uppertropospheric air, but not vice-versa.
C. Surface weather patterns can influence uppertropospheric air, and upper tropospheric air caninfluence surface weather.
D. WTF?
PHYS 189 () Midlatitude Cyclones week 11 29 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
How cold fronts at the surface generate upperlevel troughs
Assume pressure at the surfaceat A, B, and C is 1000 mb
PHYS 189 () Midlatitude Cyclones week 11 30 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Clicker question
The 500 mb height con-tours in (a) are primarily
A. zonal
B. meridional
PHYS 189 () Midlatitude Cyclones week 11 31 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Clicker question
The 500 mb height con-tours in (b) are primarily
A. zonal
B. meridional
PHYS 189 () Midlatitude Cyclones week 11 32 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Clicker question
Which flow patter islikely associated withlight winds, calm con-ditions, and no areasof widespread precipita-tion?
A. zonal
B. meridional
PHYS 189 () Midlatitude Cyclones week 11 33 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Weather break
I Real time 500 mb heights
PHYS 189 () Midlatitude Cyclones week 11 34 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Clicker question
Midlatitude cyclones generally migrate
A. west-to-east
B. east-to-west
C. north-to-south
D. south-to-north
E. in an arbitrary direction
PHYS 189 () Midlatitude Cyclones week 11 35 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Typical winter storm paths
PHYS 189 () Midlatitude Cyclones week 11 36 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Surface fronts and upper level patterns
Migration of cyclone relative to Rossby wave
PHYS 189 () Midlatitude Cyclones week 11 37 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Conveyor Belts & midlatitude cyclones
Conveyor belt model
I Cyclones are 3-dimensional entities that connect flowpatterns in the upper atmosphere with those at thesurface.
I the overall flows can be modeled by three flows orconveyor belts
I warm conveyor beltI cold conveyor beltI dry conveyor belt
PHYS 189 () Midlatitude Cyclones week 11 38 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Conveyor Belts & midlatitude cyclones
The Atmosphere
conveyor belt tutorial
PHYS 189 () Midlatitude Cyclones week 11 39 / 40
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MidlatitudeCyclones
PHYS 189
MidlatitudeCyclone life cycle
Rossby waves,vorticity, &cyclogenesis
Surface fronts andupper levelpatterns
Conveyor Belts &midlatitudecyclones
Conveyor Belts & midlatitude cyclones
Effects of climate change
Research indicates that the increase in global temperaturesassociated with increases in greenhouse gases have shiftedstorm tracks poleward.
⇒ The relative dry areas in the southwest could lose animportant source of moisture and suffer more droughts.
PHYS 189 () Midlatitude Cyclones week 11 40 / 40