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Viewed from above in the Northern Hemisphere, surface winds about about a subtropical high blow
clockwise and outward
Viewed from above in the Southern Hemisphere, surface winds about a subtropical high blow
counterclockwise and outward
The eastern flank of a subtropical anticyclone is characterized by
The western flank of subtropical anticyclone is characterized by
A broad region of light winds or calm air prevails
along the horse latitudes
Subtropical anticyclones are ---------core circulation systems.
Over a broad region about the center of a subtropical high, the horizontal air pressure graident is relatively---- and winds are ---------.
weak, light or calm
The trade winds blow out of the -------fland of the subtropical anticyclones.
In the Northern Hemisphere, trade winds blow from the
In the Southern Hemisphere, trade winds blow from the
The global westerlies blow our of the ------fland of the subtropical anticyclones.
The tropical deserts of the world are found at latitudes near 30 degrees latitude because
of the sinking air associated with the subtropical highs.
Viewed from aboce in the Nothern Hemisphere, winds above the atmospheric boundary layer blow
clockwise and parallel to isobars.
Viewed from above, surface winds blow-----about the Icelandic low.
counterclockwise and inward
The trade winds of the two hemispheres converge in the
The trade winds of the two hemispheres
diverge at the equator
The intertropical convergence zone (ITCZ)
is a discontinuous belt of cumulonimbus clouds.
A front is a narrow zone of transition between air masses that contrast in
temperature, humidity, or density.
Hadley cells are located in the-----latitudes of both hemispheres.
Hadley Cells are
similar to huge convection cells.
The intertropical convergence zone (ITCZ) is
the persistent band of cloudiness near the equator.
In the Northern Hemisphere, with the shift from winter to summer, the semi-permanent subtropical highs shift
In the Northern Hemisphere, with the shift from summer to winter, the semi-permanent subtropical anticyclones shift
In the Northern Hemisphere autumn, the ITCZ shifts
In the Southern Hemisphere spring, the suptropical high shift
The middle latitude westerlies are more energetic in ---- then in ------.
Long-waves in the westerlies undergo changes in
wavelength, number of waves, and wave amplitude.
On a typical day, ------ Rossby long waves encircle the globe.
2 to 5
Which one of the following westerly wave patterns favors the maximum north-south exchange of air masses?
The westerly wave pattern this is likely to persist for the longest time is
A blocking pressure system is associated with a ----- flow pattern in the westerlies.
Across the United States, temperature contrasts are generally greatest during a --------------- circulation pattern in the westerlies.
During droughts, when soil moisture is low, the Bowen ratio is relatively
In the Midwest, drough is most likely with a ------- circulation pattern in the westerlies.
Horizontal divergence occurs to the ---- or an upper-air trough.
Horizontal convergence occurs to the----- of an upper-air ridge.
Horizontal divergence occurs to the ------ of an upper-air ridge.
Horizontal convergence occurs to the ----- of an upper-air trough.
A synoptic-scale cyclone is most likey to develop to on the ------- side of an upper-air trough.
A synoptic-scale cyclone is most likely to develop on the -------side of an upper air ridge.
In an essentially straight jet streak viewed from above, the strongest horizontal divergence takes place in the-------quadrant.
The average winder location of the polar front jet stream is
southern United States.
The average summer location of the polar front jet sream is
The southern oscillation
is linked to the development of El Nino.
In the Northern Hemisphere, Ekman transport of surface ocean waters is about ------- of the surface wind direction.
90 degress to the left of
brings cold bottom water to the ocean surface, is the long-term average condition off the northwest coast of South America, is suppressed during El Nino, supports important fisheries.
Along the California coast, upwelling occurs when winds blow from the
An extreme and persistent El Nino
may be accompanied by weather extremes in various parts of the world.
During "neutral" condition, sea surface temperatures are highest in the ----- tropical Pacific.
La Nina -------- follows El Nino.
In equal volumes, which one of the following air masses exerts the highest surface air pressure.
In summer, at the same pressure, maritime tropical air is-------continental tropical air.
less dense than
A source region for maritime tropical air is
the Gulf of Mexico
A warm and humid air
mT maritime tropical
At teh same pressure, which one of the following air masses is least dense?
At the same pressure, which one of the following air masses is most dense in winter?
Of the following air masses, which one exhibits the greatest temperature changes between winter and summer
Usually air mass modification is most rapid when
continental polar air moves over bare ground.
In winter, continental plar air is----- maritime polar air.
A front is a narrow zone of transition between between air masses that contrast in
temperature, vapor pressure, or density
As a warm front approaches, clouds appear in which one of the following sequences:
cirrus, alostratus, stratus
A cloud that indicates warm air advection aloft:
The cloud and precipitation shield associated with a cold front typicaly is------- the cloud and precipitaion shild associated with a warm front.
A type of cloud associated with a fast-mving, well defined cold front:
Cold fronts typically travel ------- warm fronts.
The type of front formed when the leading edge of cold air merges with a warm front is known as
an occluded front.
An occluded front forms
late in the life cycle of an extra tropical cyclone.
The most common type of occlusion in the Great Lakes region is the
Surface air pressure drops when horizontal divergence aloft----------- horizontal convergence at the surface.
is greater than
In a mature extra tropical cyclone, fog, and drizzle are most likely to develop
in the cold air just ahead of the surface warm front.
If a weather station reports a wind shift from northeast to north and then northwest and a steady rain turning to snow flurries, the low center is most likey moving
from southwest to northeast, east of the station.
Precipitation tends to be steady and persistent in the --------sector of a mature extra tropical cyclone.
The coldest sector of a matue extra tropical cyclone is usually ------------ of the cyclone center.
The warmest sector of a mature extra tropical cyclone is usually ----------of the cyclone center.
The warmest air associated with a mature extra tropical cyclone is usually located
southeast of the low center.
What is the surface wind direction in the northwest sector of a mature extra tropical cyclone?
Major winter storms that most directly affect central Indiana follow the ------------- cyclone track.
Extra tropical cyclones that occur with the greatest freqeuncy over North America.
Viewed from above, the surface wind circulation about an Alberta-type cyclone is
counterclockwise and inward
If the surface wind backs from northeast to north, Boston usually experiences
cold air advection
If the surface wind veers from east to southeast to south, Baltimore usually experiences
warm air advection.
A surface wind that backs the time indicates that you are situated on the ------side of the track of an extra tropical cyclone.
Warm air advection takes place to the ---- of a ridge and to the ---- of a trough.
The relatively warm side of the track of an extra tropical cyclone
to the right of the system's forward motion.
Contrasting air masses are brought together to form fronts by the surface winds about the centers of ------------- pressure.
In the southwestern United States, heat (thermal) lows generally
An intense extra-tropical cyclones tracks up the Mississippi River Valley and passes well to the west of Chicago. As the cold front sweeps through Chicago, the wind shifts from the south to the
An example of a cold-core anticyclone is the
At the center of a polar high, the horizontal pressure gradient is weak and winds are
light or calm
Nocturnal radiational cooling is most intense
at the center of an anticyclone.
When land and water are exposed to the same intensity of solar radiaiton, the land warms------ the water.
At night, radiational cooling chills a land surface ---- an adjacent water surface.
The time of day, when a summer sea breeze is likey to be strongest is
During a lake breeze, the horizontal pressure gradient force is directed
parallel to the coastline.
The time of year when a lake breeze is most likey to develop along the Lake Michigan shoreline is
The chinook wind blows done the leeward slopes of the mountain ranges and is characteristically
warm and dry.
are not warm at he moist adiabatic rate, do not flow downhill under the influence of gravity, does not occur only on the windward slopes of a mountain range.
As a chinook wind is drawn down the leeward slopes of a mountain range,
the saturation vapor pressure increases.
A dust devil
may resemble a small tornado, is not linked to a cloud, typically causes little or not property damage.
A mountain breeze blows
downslope at night.