Wind + Circulation Patterns
What two forces combine to create geostrophic wind in the upper troposphere?
Pressure Gradient Force (PGF) and Coriolis Force.
What type of humidity is the “mass of water vapor per total mass of air”?
Specific Humidity
Which cloud type is flat and gray, resembling high fog?
Stratus clouds
What lifting mechanism occurs when air masses collide and rise?
Convergent lifting
What are the four main stages of a midlatitude cyclone?
Cyclogenesis → Open Stage → Occluded Stage → Dissolving Stage
Between which latitudes are Hadley Cells found?
0° to 30° in both hemispheres.
When relative humidity reaches 100%, what two conditions are met?
The air is saturated, and evaporation = condensation.
What prefix is used for mid-level clouds found between 2,000–6,000 meters?
alto
What type of lifting is common in Florida during summer afternoons?
Convectional lifting from surface heating
What is the average ground speed and lifespan of a tornado?
45–55 mph, lasting seconds to several minutes, average path ~7 km
Name the high-pressure zone near 30° N/S responsible for Earth’s major deserts.
The Subtropical High-Pressure Zone.
Compare the Dry Adiabatic Lapse Rate (DAR) and Moist Adiabatic Lapse Rate (MAR), which is faster, and why?
DAR (10°C/1000 m) is faster because no condensation occurs, while MAR (6°C/1000 m) slows as latent heat is released.
Which vertically developed cloud type produces thunderstorms and has an anvil-shaped top?
Cumulonimbus
During orographic lifting, which side of the mountain experiences the rain shadow effect?
leeward side
What are the two key atmospheric ingredients required for tornado formation
Strong wind shear and strong updrafts (mesocyclone formation)
Why do winds deflect to the right in the Northern Hemisphere?
Because of the Coriolis Effect caused by Earth’s rotation.
What determines whether an air parcel is stable or unstable?
Comparison of parcel temperature vs. environment - warmer air rises (unstable), cooler air sinks (stable).
How do the collision-coalescence and Bergeron ice-crystal processes differ?
Collision–Coalescence happens in warm clouds (happens when droplets merge), Bergeron Process occurs in cold clouds (ice crystals grow as droplets evaporate)
Compare the slope and air movement of warm fronts vs. cold fronts
Warm fronts have gentle slopes and gradual uplift; cold fronts have steep slopes and rapid uplift
What temperature must ocean water reach for a hurricane to form?
At least 26.5°C (80°F)
What are the two main jet streams, and around what altitudes do they occur?
Polar Jet Stream (7–10 km) and Subtropical Jet Stream (10–16 km).
What does the lifting condensation level (LCL) represent in the atmosphere?
The altitude where rising air becomes saturated (RH = 100%) and clouds begin to form
Describe the key difference between advection fog and radiation fog
Advection fog forms when moist air moves over a cool surface; radiation fog forms when the ground cools air to the dewpoint overnight
In which two atmospheric conditions does air convergence most often occur?
In low-pressure systems and along the Intertropical Convergence Zone (ITCZ).
According to the Saffir–Simpson Scale, what wind speeds classify a Category 5 hurricane?
≥155 mph (≥250 km/h)