Atmospheric and Oceanic Circulation Flashcards
Barometer
Measures atmospheric (barometric) pressure. Column of mercury (sea level = 1 ATM)
Anemometer
Measures wind speed and direction
Speed in km/h, mph, Beaufort scale
16 different directions in a compass from where it originates (westerly wind, etc)
Pressure gradient force
Cold air = dense = high atm pressure
Hot air = less dense = low atm pressure
High pressure –wind–> low pressure
Isobars
Isoline of pressure
Spacing between lines shows pressure gradient (gradual –> steep)
Coriolis force
Earth’s rotation (linear velocity varies with latitude)
Increases with velocity
Friction force
With surface, extends up to 500m
Rough + irregular surfaces produce more friction
Equatorial low pressure and ITCZ
Warmer, less dense air in the Equator rises and creates low-pressure
ITCZ: InterTropical Convergence Zone
- high/constant insolation
- warm air ascends and creates low-pressure
- air converges, bringing humidity
- humidity ascends, produces condensation
Subtropical high pressure cells
High pressure cells that are warm and dry, caused by cooling of air in Hadley cells
Around 30 degrees N/S
Hadley cells
About 30 degrees latitude
Responsible for trade winds in teh Tropics, control low-latitude weather patterns
Upper atmospheric circulation
Constant isobaric surface
- trough –> low pressure
- ridges –> high pressure
Jet streams = fast streams bw 7km and 11km, up to 300 km/h
propel airplanes
Multi year oscillations
ENSO = El Nino Southern Oscillation (avg = 5 years)
NA Oscillation
Arctic oscillation
Pacific Decadal Oscillation
Thermohaline circulation
Thermo = temperature, haline = salt content
Ocean conveyer belt
Pressure gradient + coriolis
Pressure gradient –> wind travels and gets faster
More coriolis –> wind gets deflected (to the right in the NH)
Cyclones + hurricanes
Geostrophic winds
Winds that flow parallel to isobars
