7. Friction: only with surfaceFriction: only with surface
windswinds
Friction bends the surface winds from aFriction bends the surface winds from a
straight path, and a diagonal path isstraight path, and a diagonal path is
formedformed
High
low
8. Cyclones are patterns of windCyclones are patterns of wind
flowflow
Cyclonic circulation Pattern: upward andCyclonic circulation Pattern: upward and
inward in the Northern Hemisphere (LOW)inward in the Northern Hemisphere (LOW)
Anticyclonic: Downward and outward inAnticyclonic: Downward and outward in
the Northern Hemisphere (HIGH)the Northern Hemisphere (HIGH)
Reversed in the Southern HemisphereReversed in the Southern Hemisphere
21. Wind / pressure systemsWind / pressure systems
Global pressure belts – High & lowGlobal pressure belts – High & low
pressure air masses give rise to windpressure air masses give rise to wind
systems: global circulation.systems: global circulation.
Regional pressure belts give rise toRegional pressure belts give rise to
regional wind systems: (Mistral, Bora,regional wind systems: (Mistral, Bora,
chinook), Santa Anachinook), Santa Ana
22. Monsoons & monsoonal typeMonsoons & monsoonal type
windswinds
Monsoons - SEASONAL CHANGES IN PRESSURE &Monsoons - SEASONAL CHANGES IN PRESSURE &
WINDSWINDS
California coastal pressure changes,California coastal pressure changes,
El Nino- not a wind system per se, just generates them.El Nino- not a wind system per se, just generates them.
Monsoonal winds ( seasonal, shifting),Monsoonal winds ( seasonal, shifting),
SEASONAL CHANGES BY LATITUDE: winter – highSEASONAL CHANGES BY LATITUDE: winter – high
pressure in high latitude lands, creates cool dry northerlypressure in high latitude lands, creates cool dry northerly
windswinds
summer – STH over the oceans, low latitudes- bringssummer – STH over the oceans, low latitudes- brings
rains to the east coasts of continents, dry air to the westrains to the east coasts of continents, dry air to the west
coast of continents.coast of continents.
28. Seasonal shift of pressure/windSeasonal shift of pressure/wind
patternspatterns
ASIA Pacific N.Amer. Atl. EurASIA Pacific N.Amer. Atl. Eur
Winter: Icel.LWinter: Icel.L
Siberian H Aleutian L HawiianHSiberian H Aleutian L HawiianH
Summer:Summer:
Asiatic L Hawaiian H Azores HAsiatic L Hawaiian H Azores H
31. Southern hemisphereSouthern hemisphere
Variations are less extreme because ofVariations are less extreme because of
the dominance of water in the hemispherethe dominance of water in the hemisphere
32. RECAP: Additional wind flows-RECAP: Additional wind flows-
override prevailing winds for a timeoverride prevailing winds for a time
Surface winds – convective: valley,Surface winds – convective: valley,
Mountain, Upper level – Rossby waves,Mountain, Upper level – Rossby waves,
jet streams (polar ( -250 mph) westerlyjet streams (polar ( -250 mph) westerly
----subtropical jet ( westerly winds)----subtropical jet ( westerly winds)
Tropical easterly jet ( summer in N.Tropical easterly jet ( summer in N.
Hemisphere)Hemisphere)
GIVE VARIETY TO LOCAL WEATHERGIVE VARIETY TO LOCAL WEATHER
PATTERNSPATTERNS