Final Exam Flashcards
Primary Circulation
general global circulation: average air flow around globe and created by unequal heating of earth’s surface
Secondary Circulation
related to pressure belts migratory high pressure and low pressure systems
Tertiary Circulation
includes local winds and temporal weather patterns
General Atmospheric circulation
reason there is different weather patterns, jet streams, deserts, and prevailing winds; caused by rotation of Earth and amount of heat different parts of Earth receive.
Air mass
a large body of air with similar temperature and moisture characteristics in any horizontal direction
Air mass and Earth’s surface
each area of Earth’s surface impacts its temperature and moisture characteristics to overlaying air; Effect of the surface on the air creates regional air masses w/ homogenous mix of temperature, humidity, and stability
Classification of air masses
air masses are classified moisture and temperature
Moisture
“m” for maritime (wet) & “c” for continental (dry)
Temperature
“A” for arctic, “P” for polar, “T” for tropical, “E” for equatorial, & “AA” for antartic
Four categories for the classification of air masses
(cP, mP, cT, mT)
cP
continental polar: air masses form only in Northern Hemisphere and developed in cold weather conditions; displaces moist and warm air: producing lifting, cooling and condensation
mP
maritime polar: air masses in the Northern Hemisphere exist over the northern oceans
mT
maritime tropical: two maritime tropical air masses that influence North America
mT Gulf/ Atlantic:
unstable and active in spring and fall
mT pacific:
stable to conditionally unstable and generally lower in moisture content and available energy
cT
continental tropical: hot dry unstable at low levels, stable at upper levels, over Mexican plateau region
If air mass is colder than surface over which it is moving
“k” is added
If air mass is warmer than the surface over which it is moving
“w” is added
Zonal flows (winds)
move east or west along parallels of latitude
Meridional flows (winds)
move north or south along meridians or parallels to lines of longitude
Intertropical Convergence Zone (ITCZ)
Where northeast trade winds in the northern hemisphere and the southeast trade winds in the southern hemisphere meet
NE and SE Trade winds
comes from the east located between the equator and 30 degrees latitude in both hemispheres
Doldrums
another name for intertropical convergence zone
Horse latitudes
around 30 degrees latitude, sinking air creates a belt of high pressure which causes weak winds
Pacific High
moves northward during summer, during winter moves south allowing precipitation to SW US
Bermuda High
transports warm, moist subtropical air to US and southern Canada, air can be unstable
Cyclones
Southwestern pacific ocean
Lightning
Gigantic electrostatic discharge between the cloud and the ground, other clouds, or within a cloud
Chinook winds
Dry winds blowing down on the lee-side of the mountains ranges
Thermocline
o Layer within a body of water or air where the temperature changes rapidly with depth
o Thermos= heat
o Cline= slope
El nino
refers to eastward movement of warm water from the western equatorial pacific to the eastern equatorial pacific
La Nina
after El Nino phase, la Nina occurs; Unusually cold weather that is found in eastern Pacific Ocean; cold episodes
a tropical line
A trough or cyclonic curvature maximum in the trade wind easterlies
a dry line and its symbol
A boundary separating moist and dry air masses and lies north-south across the central and southern high plains states
a trough and its symbol
An elongated area of relatively low atmospheric pressure
a squall line and its symbol
A line of active thunderstorms either continuous or with breaks
a cold front and its symbol
o Transition zone where a cold air mass is replacing warmer air mass
o Move from northwest to southeast
a warm front and its symbol
o Transition zone where a warm air mass is replacing a cold air mass
o Move from southwest to northeast
Occluded front and its symbol
Occurs when a fast-moving cold front overtakes a warmer front; cold air wedges the warm front upward = precipitation
Frontolysis Process
Fronts can weaken with time
Microburst
a sudden, powerful, localized air current, especially a downdraft.
Oceans and their properties
Regulate climate, cycle mass, and transfer energy around the globe
Isothermal
Equal or constant temperature; not present at high latitudes
Midlatitude Westerlies
global wind system that comes from the west
Polar easterlies
global wind system that comes from the east
Icelandic lows
Observed average surface pressure and winds during January
Aleutian lows
genesis region for cyclones impacting pacific NW
Observed average surface pressure and winds during January
Trend technique
o Rate x time = distance
o If phenomenon is in a steady state or is moving at a constant speed
Surface winds, flowing into Low, out of High, crossing isobars
When low or high pressure develops more locally, the resulting high and low pressure regions are cell-like systems, and isobars describe the patterns of air pressure will include one or more closed circular isobars
Polar front
The boundary at which air flowing away from the polar regions collides with the warmer air from the lower latitudes
Polar jet stream
jet stream that can bring down cold weather conditions from the north
Polar high
Zone of high atmospheric pressure at high latitudes
Distribution of precipitation globally
Equator:
- Higher temperatures (more rising, cooling air
masses, which results in precipitation)
Poles:
- Lower temperatures (less rising, cooling air masses)
convergence
the state of separate elements joining or coming together
divergence
the act of moving away in different direction from a common point
subtropical deserts
A biome prevailing at approximately 30° N and 30° S, with hot temperatures, extremely dry conditions, and sparse vegetation.
subtropical jet stream
jet stream that can bring up warm weather conditions from the south
seasonal variations of Hadley cells
convection cells in the atmosphere through which warm air rises, releases its moisture, and returns poleward as cool, dry air.
poleward energy transport atmospheric
Air moving equatorwards over the surface of the Earth takes up heat from the oceans and continents
poleward energy transport oceanic
Heat is transferred in a northward, heat is absorbed by the tropical waters and is then transferred to the high latitudes, where it is finally given up to the atmosphere.
temperature inversions
atmospheric condition in which warm air traps cooler air near the earth’s surface
tornado and its scale
localized and violently destructive windstorm occurring over land characterized by a funnel-shaped cloud extending toward the ground
thunderstorms (causes of birth)/ locations
1: Sun heats surface during the day, warms air and starts to rise (updraft); if air is moist, it condenses into a cumulonimbus cloud
2: Becomes to large and water becomes heavy, cool dry air starts to enter the cloud, cool air is heavier and starts to descend the cloud; down draft pulls the water down making rain
Location: Florida gulf coast and colorado
