cture

ET C n/equatorward.Core height.

B p. 58

Lecture 15. Upper Atmospheric Cyclone Stru

yclone mainly draws warm air up/poleward, cold air dow of cyclone rotates counterclockwise, tilts westward with

TW

ves - 3000-5000 to trough,tionary.

ves: 1000-2000to trough, move mb winds.ays easily dis-ble.

‘cyclonic’lockwise - NH)inds

anticyclonic’se - NH) spin

TW

Long and Short Waves

Long wakm ridgenearly sta

Short wakm ridgewith 500...not alwtinguisha

Troughs:(countercspin of w

Ridges: ‘(clockwi

B p. 55

ves

M

Movement of Short Waves Through Long Wa

EO

• Vor

• TotRel

+ Am

• Am

• Ab

Relative

nt

No ambient vort

Positive ambient vort.

Negative ambient vort.

Vorticity

ticity is ‘spin’ of air parcel about vertical axis.

al or ‘absolute’ vorticity has two parts:ative vorticity = Spin of air relative to earth

bient vorticity = vertical part of earth’s spin

bient vorticity is large at poles, zero at equator.

solute vorticity only changed by stretching

Ambie

More absolutevorticity

Less absolute vorticity

CompressionStretching

• Are und the globe.• Inv r keeps the same

abs ave.

• Na who was one ofthe ther.

Long (Rossby) waves

set up by the pattern of oceans, land, and mountains aroolve little stretching or compression of air columns, so aiolute vorticity as it moves from W to E throughout the w

med after a famous meteorologist of the 1920s and 1930s first people to recognize the role of the jet stream in wea

More ambient vort in ridgeNegative rel vort in ridge, positive rel vort in trough,Same absolute vort in both.

E

N

Jet stream winds

(TWB p 54)

Storms crossing over the Rockies

• Sur• Low

of M• Co

sto

(EOM)

Storm Tracks

face lows disappear over the Rockies formation in lee of Rockies and Gulfexico

ld highs descend from Canada behindrms