UNIT 9 Flashcards
(37 cards)
Cloud
Visible masses of suspended, minute water droplets and or ice crystals
Cloud formation ingredients
moisture, rising motion, condensation nuclei
Classify clouds based on..
height and shape
cirrus
thin; wispy cloud; composed of ice crystals; typically found at higher levels (above 6 km)
stratus
Flat layered appearance, fairly thin, and cover a large region
- low: stratus; below 3km (10,000 ft) - middle: altostratus; 3-6 km (10,000-20,000 ft) - upper: Cirrostratus; above 6 km
nimbostratus
low level thin cloud; rain producing
cumulonimbus
very tall cumulus clouds, anvil shaped top, violent weather; extends from 500 m to 12 km
cumulus
Thick, puffy masses that often develop to great heights
- Low: Cumulus/ stratocumulus; (Below 3 km) - Middle: altocumulus; (3-6 km) - Upper: cirrocumulus; (above 6 Km)
Mammatus Clouds
usually associated with severe weather and hail
Lenticular Clouds
found on top of mountains
Kevin-Helmholtz clouds
wave like appearance; turbulence
Contrails
help block sun radiation and prevent long wave radiation from escaping at night
Fog
visible masses of suspended, minute water droplets and or ice crystals; very near to the ground; NEEDS MOISTURE AND CONDENSATION NUCLEI
Does fog form adiabatically or diabatically?
diabatically; air reached saturation through contact with cold air or exchanges of sensible heat with a colder surface( supports less moisture)
radiation fog
occurs as the surface loses its heat to space; the air near the ground cools; water vapor condenses; most common type, generally occurring on clear, cool nights; thickets before dawn
Advection Fog
Warm moist air advects over cold surface and cools to dew point; common near oceans; can be found over snow-covered grounds; thicker band more persistent; ex: San Francisco (Advection is horizontal transport of something)
steam fog
cool air moves over warm water, producing enough moisture to saturate the air above it
DEW
visible masses of minute water droplets; water droplets on the surface. NEEDS MOISTURE AND CONDENSATION NUCLEI & FORMS DIABATICALLY
precipitation
falling water/ice from the sky
rain
precipitation that falls when temperature is above freezing
sleet
partially melted snowflake that refreezes before it hits the ground
snow
ice crystals that fall through atmosphere and do not encounter any layers above freezing temperatures
freezing rain
precipitation that falls as rain, but freezes when it comes in contact with sub- freezing surface
hail
precipitation that forms ice crystals are blown about within a tall and very moist cloud; NEEDS MOISTURE, CONDENSATION NUCLEI, AND RISING MOTION