Download Last time Clouds and Fog Cloud Formation Processes

9/29/2010
GEOG 1001: Clouds and Lifting
September 30th, 2010
Dr. Bob Ross
Last time
• Polarity of water molecule and strength of
hydrogen bond.
• Phase changes.
• Relative Humidity (changes with temperature)
• Atmospheric Stability (ELR VS DAR and MAR)
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Clouds and Fog
• Cloud Formation Processes
• Cloud Types and Identification
• Fog
Cloud Formation Processes
• Moisture droplet
• Cloud-condensation nuclei
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Raindrop and Snowflake Formation
Moisture Droplets
Figure 7.21
Figure 7.20
Cloud Types and Identification
Cirrus
Bright and fluffy clouds
Low clouds
Figure 7.22
Figure 7.22
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Cirrostratus
Altocumulus
Figure 7.22
Altostratus
Figure 7.22
Nimbostratus
Figure 7.22
Figure 7.22
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Stratus
Cumulus
Figure 7.22
Cumulonimbus
Figure 7.22
Cumulonimbus Development
Figure 7.22
Figure 7.23
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Advection Fog
Fog
• Fog is a cloud layer on the ground; several
types:
• Advection fog (warm air moves over cold)
• Evaporation fog
• Upslope fog
• Valley fog
• Radiation fog
Figure 7.24
Evaporation Fog
Valley Fog
Figure 7.25
Figure 7.25
Figure 7.26
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Atmospheric Lifting Mechanisms
Atmospheric Lifting Mechanisms
•
•
•
•
Convergent Lifting
Convectional Lifting
Orographic Lifting
Frontal Lifting (Cold and Warm Fronts)
Figure 8.6
Orographic Precipitation
Convection over Florida
Figure 8.8
Figure 8.9
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Orographic
Patterns
Frontal Lifting
• Cold Fronts
– Cold air forces warm air aloft
– 400 km wide (250 mi)
• Warm Fronts
– Warm air moves up and over cold air
– 1000 km wide (600 mi)
Increased precipitation
intensity
Increased precipitation
frequency
Figure 8.10
Cold Frontal Lifting
Warm Front
Figure 8.11
Figure 8.13
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Summary
• Cloud formation
• Cloud types
• Atmospheric lifting
– Convergent Lifting
– Convectional Lifting
– Orographic Lifting
– Frontal Lifting (Cold and Warm Fronts)
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