Week 7 Earth Science
A large chunk of air usually 1000 miles or more in diameter
4 designations used to describe air masses
Polar (P cold) tropical ( Twarm) continental (c dry) and maritime (m wet).
The first two such as polar and tropical are used to describe ____. Whereas the last two such as continental and maritime refer to _____.
Temperature (cP), moisture.(mT)
5 main air masses affecting the continental US. See p 542
Continental arctic (cA): Very cold and dry. Continental polar (cP) Cold and dry. Maritime polar (mP) Cool, humid. Maritime tropical (mT) warm, humid. Continental tropical (cT) Hot, dry.
Air masses can ____ as they move across the Earth. Interaction between the air masses and local geography and weather conditions can produce different _______ events.
Boundaries between air masses
Four types of fronts?
Warm, cold, stationary, and occluded
Boundary between cold and warm air masses with no movement
Moving cold air overtaking warm air moving in the same direction.
Middle latitude cyclones?
Low pressure areas with counterclockwise winds
3 main severe weather types
Thunderstorms, Tornadoes and hurricanes
Formed when warm humid air rises into an unstable atmosphere and produce thunder and lightning along with wind gusts, rain, or hail.
Tornadoes represent? How are they formed?
Small regions of extremely low pressure.
When wind speed at the ground is slower than upper wind speed and updrafts are created
How is the strength of Tornadoes measured?
What does the Fujita Scale do?
Classifies wind, speed, and damages.
How can the possibility of a tornado be predicted? (5) =?
temperature, barometric pressure, wind speeds, directions, and radar echoes. Tornado watch
When are tornado warnings issued?
When a tornado has been seen
Cyclonic storms. Considered to be the largest and strongest storms.
Average of US hurricanes/yr?
How are hurricanes formed?
Over warm, late summer, ocean water
2 other names for hurricanes in the Pacific region?
Typhoons or cyclones
How are hurricanes rated and on what scale?
based on pressure and wind readings on the Saffir Simpson scale.
When is the rating of hurricanes taking place?
during the progression of a tropical depression to a tropical storm to a hurricane.
Damage from a tornado vs a hurricane
Tornado: Wind damage. Hurricanes: High winds, large amounts of rainfall and flooding due to high ocean waves (storm surge)
Average or long term weather
Climate system involves 5 areas?
atmo, hydro, geo, bio, and cryosphere ( region covered with ice or snow)
The most widely studied change in Earth's climate system currently?
How are climates classified?
5 categories within the Koppen classification
A-humid tropical B-dry C-humid middle latitude with mild winters D-humid middle-latitude with severe winters and E-polar
What is the classification of AR?
Cfa= humid subtropical
No winter climates. All months have an avg temp of 18 C
Climates where evaporation exceeds precipitation there is always a h20 lack.
humid middle latitude with mild winters?
Mild winters. Avg temp of coldest month is below 18 C and above -3.
humid middle latitude with severe winters?
Severe winters. Avg temp of coldest month is below -3 C and warmest month avg exceeds 10 C
No summer climate. Warmest month avg is below 10 C