Exam 3 Study Guide Flashcards
(84 cards)
Does the sierra Nevada mountains have more snow typically than the rest?
Yes
What is an upslope storm?
Snow storm along the rocky Mountains caused by air flowing westward (to the west)
What characteristics of mountains influence snowfall?
Location (Near ocean), Height, Steepness
What is an atmospheric River?
Narrow flow of moist air in the lower and middle troposphere.
What does Atmospheric Rivers look like on satellite?
Long stream of clouds, or high water vapor concentration.
What is orographic lifting?
Forced ascent air that occurs on the windward (upslope) side of the mountains.
Would more snow be expected to fall on the windward or leeward side of a mountain range?
Windward side
Why does more snow happen on the windward side of the mountain?
Air rises on the windward side of a mountain, creating clouds and precipitation. Air sinks on the leeward side, warming and drying air.
What is the melting point?
Defines the freezing/melting point of water.
What type of precipitation would happen above and below the melting point?
Above - Snow
Below - Rain
What is a rain shadow?
A region that experiences little precipitation because it is located on the leeward slope of a mountain range.
Where are rain shadows located?
Leeward side of the mountain.
Where would the ideal locations be for low-pressure system and high-pressure system for heavy storm on the east slope of Colorado’s Front Range?
High-pressure north of colorado
and Low in south west corder of colorado
What general location is the surface wind blowing during an upslope storm in eastern colorado?
Easterly (Northeast, East, or southeast)
What surface wind direction factors heavy snowfall in Denver, colorado?
Northeast
What maximum speeds can downslope windstorms attain?
Gusts may exceed 100 knots (115mph)
What three factors determine the temperature of chinook winds?
- Temperature of air upstream of the mountains?
- Latent heat release in the clouds upstream
- Adiabatic Warming during descent.
Why is the dewpoint temperature typically lower on the leeward side of a mountain compared to the windward side during a downslope windstorm?
Precipitation falls out of the cloud on the windward side of the mountains. The dewpoint lowers when the temp hits it.
What three factors are common to weather patterns that produce Chinook winds?
- Stable layer upstream of a mountain a Kilometer or two above the mountaintop.
- Strong surface pressure gradient across the mountain
- Levels near mountaintop, background flow that is strong and from west.
Where do Santa Ana winds occur?
Southern California
How do Santa Ana winds differ from chinook winds near boulder?
- Santa Annas are
- more frequent
- Less intense
- Winds from east
Why are Katabatic winds most common in Greenland and Antartica?
Katabatic winds require high altitude, large ice sheets - which are present in Greenland and Antartica.
What is the difference between Foehn and Bora?
- Foehn - Warm downslope windstorm
- Bora - Cold Downslope windstorm
What is a lee wave?
A wave in airflow that forms as air passes over the mountain to the lee side.