WEATHER PATTERNS Flashcards
4 things the amount of water vapour in the air depends on
- absolute humidity
-specific humidity
-relative humidity
-mixing ratio
what is vapour pressure
the pressure exerted by water vapor molecules in an air parcel
–> more water molecules = higher vapor pressure
what is Saturation vapor pressure
the pressure at which an air parcel will be saturated (full) -> this changes with temperature
how to calculate the relative humidity
( vapor pressure / saturation vapor pressure ) x 100%
i.e. it is the percentage saturation
how can relative humidity change
due to changes in water vapor content,
OR due to changing temperatures
does cold or warm air have the ability to hold more vapour
Warm air has the ability to hold more vapor than cold air (saturation vapor pressure increases)
2 ways we classify weather systems.
Size + Lifetime
where on earth is there no Coriolis effect
equator - No Tropical cyclones
whats the general process of a tropical cyclone formation
- Disorganized cluster of thunderstorms
- Air travels toward area of lowest pressure - Wind picks up moisture from ocean
- Pressure falls, winds increase, wind rotates
*can transition into extra-tropical cyclones
how does a Disorganized cluster of thunderstorms from
Rising air creates saturation and condensation
Condensation -> Latent heat release -> Warming
Lowers pressure more
A cyclic process
conditions needed for tropical cyclone development
- Warm water ( > 26 C, > 78 F)
- Small vertical wind shear (Latent heat release)
- Reasonable distance from equator (Coriolis Force)
- Lots of humidity
- Initial disturbance
how does an Extra-tropical cyclones form
derive energy from temperature contrasts rather than warm ocean waters
- Polar front theory (developed around World War I)
- Considers the polar front as a semi-continuous boundary separating cold, polar air from more moderate mid-latitude air
- Cyclogenesis is occurring here
what indicates that a storm is still intensifying
Comma clouds
Two types of ocean current
- Surface currents – wind-driven
- Thermohaline currents - slow, density driven below the pycnocline
why does The North Atlantic Gyre consists of four major currents
each has distinct flow characteristics + temperature due to:
- Ekman spiral
- Ekman suction / pumping
what does ekamn spiral refer to
how the wind-driven surface ocean currents change direction with increasing depth due to the Coriolis effect
what does Ekman suction / pumping refer to
vertical water movement due to wind-driven circulation - causes upwelling and downwelling
what is Planetary vorticity
vorticity associated with rotation of earth, 𝜁p
what is Relative vorticity
vorticity viewed in from within the Earth’s rotating reference frame, 𝜁r
western currents characteristics
Fast warm narrow
eastern currents characteristics
slow cold broad
why is the western and easter currents different
western intensification - westward boundaries generates spin in the opposite direction to the net spin on the ocean
how would ocean gyres look if there was no Coriolis effect
symmetrical
a characteristic that can tell you about surface currents
Sea surface height - Wind can cause vertical movement of surface waters
what is Langmuir Circulation a result of
wind sheer + stokes drift
where does upwelling happen
everywhere except the 4 places that sinking happens – sinking happens much slower
how does oceanic evaporation occur
Cold air passing over warm water -> very moist air
2 famous climate patterns that effect atmospheric
circulation and weather patterns
El Niño (wind slows down) & La Niña (wind speeds up)
what can be used to Measure sea surface temp
temperature buoys
Autonomous Research Tools
