Dew is most likely to form on: |
Clear, calm nights |
The name given to a liquid drop of dew that freezes when the air temp drops below freezing: |
Frozen dew |
The cooling of the ground to produce dew is mainly the result of: |
Radiation |
For frozen dew to form, |
The air temp must drop to freezing or below |
Suppose it is a winter night and at about 10 p.m., the air cools to the dew-point temperature and a thick radiation fog develops. If the air continues to cool during the night, in 5 hours the dew point temperature will probably: |
Decrease as the air becomes drier |
Particles that serve as surfaces on which water vapor may condense are called: |
Condensation nuclei |
Frost forms when: |
Water vapor changes directly into ice in a process called deposition |
On a humid day, the ___ causes salty potato chips left outside uncovered bowl to turn soggy. |
Attraction of water by hygroscopic condensation nuclei |
Frost typically forms on the inside of a windowpane (rather than the outside) because: |
There is more water vapor touching the inside of the pane |
Condensation nuclei may be: |
Particles of dust, nitric acid particles, smoke from forest fires, and salt from the ocean (all of the above) |
Condensation nuclei are important in the atmosphere because: |
They make it easier for condensation to occur in the atmosphere |
Under what circumstances could the relative humidity exceed 100% without producing fog? |
There are no condensation nuclei present |
wet haze forms when the relative humidity is: |
Less than 100% |
On a cold winter morning, the air near the surface is full of smoke particles. If fog should form in this air, it would probably be __ fog that forms in cleaner air. |
Thicker than |
High fog is also called __. |
Stratus |
When radiation fog "burns off", the fog tends to dissipate: |
From the bottom up |
When fog "burns off", it: |
Evaporates |
On a clear night, the minimum temp drops to 34°F. The following night, fog forms early in the evening. It is a good but the minimum temp will not be as low because of the: |
Enhancement of the greenhouse effect by the fog cloud |
Winter fog in the Central Valley region of California is mainly due to: |
Radiation cooling |
On a cold, winter morning, the most likely place for radiation fog to form is: |
In a valley |
The fog that forms off the coast of the Newfoundland is mainly a form of: |
Advection fog |
Along an irregular coastline, advection fog is more likely to form at the headlands than at the beaches because of the __ surface winds and __ air. |
Converging, Rising |
If the fog is forming at Denver, Colorado, and the wind is blowing from the east, then the fog is most likely: |
Unslope fog |
Exhaled breath from your mouth can condense whenL |
It is very cold, it is warm and humid, the addition of water vapor from your breath causes the airs realtive humidity to exceep 100% |
When you see your breath on a cold morning, the air temp: |
Can be above or below freezing |
The use of helicopters to mix the air and disperse radiation fog at airports is effective provided that: |
The liquid water content of the fog is high |
On a cold, calm autumn morning, the formation of fog above a relatively warm lake would most likely be: |
Steam fog |
Which for does not necessarily form in air that is cooling? |
Evaporation (mixing) fog |
Frontal fog most commonly forms as __ raindrops fall into a layer of __ air. |
Warm, Colder |
Clouds are classified by their __. |
Appearance |
A reasonably successful method of dispersing cold fog is to: |
Seed the fog with dry ice |
Fog is a major hazard to aviation. |
True |
Which association below is NOT correct? |
Altostratus-high cloud |
At which city might you be able to observe cirrus clouds at an altitude of 3,000 m (0,000 ft) above the surface? |
Barrow, Alaska |
Even at high elevations where cirrus clouds are found, liquid water still exists in the clouds. |
True |
Which association below is not correct? |
Cumulus congeestus – anvil top |
Which cloud is LEAST likely to produce precipitation that reaches the ground? |
Cirrocumulus |
In middle latitudes, which cloud will have the highest base? |
Cirrostratus |
A halo around the moon means that: |
Cirrostratus clouds are present |
Which cloud type is composed of ice crystals and can cause a halo to form around the sun or moon? |
Cirrostratus |
Which of the following associations is not correct? |
Stratocumulus – Cloud of vertical development |
Light or moderate-but-steady precipitation is most often associated with __ clouds. |
Nimbostratus |
In the middle latitudes, with cloud will have the lowest base? |
Stratocumulus |
Which of the following cloud types would be found at the highest elevation above the earth’s surface? |
Noctilucent |
Which of the following pairs of cloud types could be very similar in appearance? |
Altocumulus and Cirrocumulus |
Which clouds often appear in parallel waves or bands? |
Altocumulus |
A "mackerel sky" describes what type of cloud? |
Cirrocumulus |
When viewed from the surface, the smalles individual cloud elements (puffs) are observed with which cloud? |
Cirrocumulus |
Cirrus clouds are composed primarily of: |
Ice particles |
Detached clouds of delicate and fibrous appearances, without shading, usually white in color and sometimes of a silky appearance are: |
Cirrus |
Suppose the sky is completely covered with a thin, white layered-type cloud. You look at the ground and see that the objects cast a distinct shadow. From this you conclude that the cloud type must be: |
Cirrostratus |
At middle latitudes, the base of an altostratus or altocumulus cloud would generally be found between: |
6,500 and 23,000 ft |
A middle cloud that sometimes forms in parallel waves or bands is: |
Altocumulus |
A dim, "watery" sun visible through a gray sheet-like cloud layer is often a good indication of __ clouds. |
Altostratus |
The name given to ragged-looking clouds that rapidly drift with the wind beneath a rain-producing cloud is: |
Scud |
An anvil-shaped top is most often associated with: |
Cumulonimbus |
If you hold your hand at arm’s length and cloud elements appear to be about the size of your fist, the cloud type is probably: |
Stratocumulus |
The name given to a towering cloud that has not fully developed into a thunderstorm is: |
Cumulus congestus |
A low lumpy cloud layer that appears in rows, patches, or rounded masses would be classified: |
Stratocumulus |
Hail is usually associated with what cloud? |
Cumulonimbus |
The cloud with the greatest vertical growth is: |
Cumulonimbus |
As Apollo 2 ascended into the atmosphere, the height of the surrounding clouds was noted to be 42,000 ft. A lightening strike was seen within these clouds, indicating that they must have been: |
Cumulonimbus |
Which of the following clouds would form in the stratosphere> |
Nacreous |
Which cloud forms in descending air? |
Mammatus |
Which below is not a way in which a contrail may form? |
Due to heating of the air by the engine exhaust |
The small, smooth cloud that may form just above the top of a towering cumulus clouds is called (a): |
Pileus cloud |
The cloud-like streamer often seen forming behind an aircraft flying at high altitude is called: |
Contrail |
Clouds that have a characteristic lens-shaped appearance are referred to as: |
Lenticular |
Clouds that appear as bag-like sacks hanging from beneath a cloud are: |
Mammatus |
An altocumulus in the form of parallel waves would be describes as an altocumulus __. |
Undulatus |
Another name for a "mother of pearl" cloud is: |
Nacreous cloud |
"Luminous night clouds: are aka: |
Noctilucent clouds |
Which term below describes a situation in which clouds cover between one-tenth and five-tenths of the sky? |
Scattered |
When clouds are viewed near the horizon, the individual cloud elements usually: |
Appear closer together than is actually the case |
Which of the following can be used to determine the height of cloud bases? |
Ceiling balloons, rotating-beam ceilometer, fixed-beam ceilometer |
If a piolet balloon rises at a rate of 00 m per min, and if it disappears into a deck of stratus clouds, 500 m (5,000 ft) thick in 5 mins, what is the ceiling of the cloud layer? |
500m (1,600 ft) |
Which of the following would provide the most accurate method of determining cloud base altitude? |
Ceilometer |
Infrared and visible satellite images might provide: |
A way of determining cloud thickness and altitude |
On an infrared satellite image, low, warm clouds appear __ and high, cold clouds appear __. |
Gray, White |
Infrared satellite images are computer enhanced to: |
increase the contrast between specific features in the picture, show where thick clouds with cold tops are located, show where clouds with tops near the freezing level are located. (all of the above) |
Satellite images taken of clouds at night use: |
Emitted infrared light |
If a cloud appears white on a visible satellite image and gray on an infrared image, then the cloud could be: |
Stratus |
The TRMM (Tropical Rainfall Measuring Mission) satellite provides information on tropical: |
Clouds, precipitation, storms |
Which of the following is NOT a name given to a satellite? |
SCUD |
Geostationary satellites: |
orbit the earth once each day, remain above a fixed spot above the equator, are placed in higher orbits than most polar orbiting satellites. (all of the above) |
Satellites can: |
monitor the amount of snow cover, provide information about the earth-atmosphere energy balance, provide information about surface water temperatures, monitor the movement of icebergs. (all of the above) |
Polar orbiting satellites: |
on each successive orbit view an area to the west of the previous orbit. |
A rotating-beam ceilometer is useful for |
Determining Visibility for pilots |
Lenticular clouds typically form ____ a mountain range. |
Downwind |
When temperatures are below freezing, the temperature to which air must be cooled in order for a phase change to occur is called the: |
Frost point |
Dew, frozen dew, and frost form when the below-freezing layer of air is: |
Shallow |
On humid days, salt in saltshakers sometimes becomes moist and no longer pours out easily. The salt can be described as: |
Hygroscopic |
Radiation fog typically forms on: |
Clear, calm nights |
In hilly areas, cold air typically collects: |
In valleys |
When fog is "burning off," the cloud droplets are preventing solar radiation from reaching the ground. |
False |
Stratus and high fog are: |
The same thing |
Advection fog is often observed along the Pacific coast during summer, as westerly winds carry moist air toward the shore. The fog forms because the surface water near the coast is ____ the surface water farther offshore. |
Much colder than |
Suppose two ocean currents with different temperatures are flowing next to one another. If the wind blows perpendicular to the currents, we would expect to find |
Advection fog |
Upslope fog forms because air ____ as it flows up a hill or mountain range. |
Cools adiabatically |
Suppose two unsaturated air masses mix horizontally. The resulting mixture cannot possibly be saturated. |
False |
In order to be effective, fog lamps on cars should be directed: |
Slightly downward |
Which two clouds can produce precipitation? |
Cumulonimbus, nimbostratus |
Which of the following clouds are almost always composed of ice crystals? |
Cirrus, cirrostratus, cirrocumulus |
Stratus clouds are typically puffy and form by convection. |
False |
Which below best describes the solute effect? |
Water droplets dissolve hygroscopic nuclei and condensation can occur at relative humidities less than 100% |
Which statement below best describes the curvature effect? |
Small droplets evaporate more quickly than large droplets |
Condensation onto hygroscopic nuclei is possible at relative humidities less than 00 percent due to the: |
Solute effect |
Which of the following is NOT an important factor in the production of rain by the collision-coalescence process? |
Number of ice crystals in the cloud |
Which cloud type below will only produce precipitation by the collision-coalescence process? |
Thick, warm cumulus cloud |
Large raindrops fall __ than smaller raindrops, and have a __ terminal velocity than smaller rain drops |
Faster, Greater |
Which cloud would most likely produce drizzle? |
Stratus |
The merging of liquid cloud droplets by collision is called: |
Coalescence |
If you observe large raindrops hitting the ground, you could prob say that the cloud overhead was __ and had __ updrafts. |
Thick; Strong |
If rain falls on one side of a street and not the other side, the rain most likely fell from a: |
Cumulonimbus cloud |
During the ice crystal process of rain formation, |
ice crystals grow larger at the expense of the surrounding liquid cloud droplets |
The temp at which you would expect a cloud to become completely glaciated is: |
-40 degrees |
Homogeneous nucleation occurs when: |
Small, non-water particles (usually called condensation nuclei) serve as sites for cloud droplet formation |
When only ice crystals exist in a cloud, the cloud is said to be: |
Glaciated |
Ice nuclei may be: |
Ice crystals, certain clay minerals, bacteria in decaying plant matter |
Supercooled cloud droplets are: |
Liquid droplets observed at temps below 0 oC or (32 oF) |
At the same sub-freezing temp, the saturation vapir pressure just above a liquid water surface is __ the saturation vapor pressure above an ice surface. |
Greater than |
Contact nucleation is: |
Involved in contact freezing. Can be just about any substance. |
The growth of a precipitation particle by the collision of an ice crystal (or snowflake) with a supercooled liquid droplet is called: |
Accreation |
Cloud seeding using silver iodide only works in: |
Cold clouds composed of ice crystals and supercooled droplets |
Which of the following conditions would be most suitable for natural cloud seeing by ice crystals? |
A cirriform cloud lying directly above a lower cloud deck |
What are the two main substances used in cloud seeding? |
Silver iodide, dry ice |
After a rainstorm, visibility typically: |
Improves |
Rain which falls from a cloud but evaporates before reaching the ground is referred to as: |
Virga |
The most common ice crystal shape: |
Dendrite |
Fall streaks usually __ before reaching the ground. |
Sublimate |
Snowflakes or ice crystals falling from high cirriform clouds are called: |
Fall streaks |
A light shower of snow that falls intermittently from cumuliform clouds for a short duration is known as: |
Flurries |
The creaking sound produces by walking on snow is most common on: |
New snow when the air temp is below -10 deg C |
Which below best describes why a fluffy covering of snow is able to protect sensitive plants and their root systems from damaging low temps? |
Snow is a good insulator |
Large, heavy snowflakes are associated with: |
Moist air and temperatures near freezing |
Fall streaks most often form with: |
Cirrus clouds |
A true blizzard is characterized by: |
Low temperatures, strong winds, reduced visibility, blowing snow |
The largest snowflakes would probably be observed in ____ air whose temperature is ____ freezing. |
Moist; near |
In order for falling snowflakes to survive in air with temperatures much above freezing, the air must be ____ and the wet bulb temperature must be ____. |
Unsaturated; at or below freezing |
In the winter you read in the newspaper that a large section of the Midwest is without power due to downed power lines. Which form of precipitation would most likely produce this situation? |
Freezing rain |
Which of the following might be mistaken for hail? |
graupel |
A raindrop or partially melted snowflake that freezes into a pellet of ice in a deep subfreezing layer of air near the surface is called: |
Sleet |
Which type of precipitation would most likely form when the surface air temperature is slightly below freezing and the air temperature increases as you move upward away from the ground? |
Freezing rain |
The primary method used in preventing the growth of large, destructive hailstones is to inject a thunderstorm with large quantities of: |
Silver iodide |
Hail deposited in a long narrow band is known as a: |
Hail streak |
Precipitation with the greatest size (diameter) is: |
A hailstone |
Glaze is another name for: |
Freezing rain |
You would use a wooden stick to measure rainfall in the: |
Standard rain guage |
An amount of precipitation measured to be less than one hundredth of an inch (0.25 mm) is called: |
A trace |
If a city were to receive /2 inch of rain in the morning and then 5 inches of snow that afternoon, about how much precipitation would the weather service report for that day? |
1 in |
After a snowstorm, the newspaper reports that Buffalo, New York, received .50 inches of precipitation. If we assume an average water equivalent ratio for this snowstorm, then Buffalo received about ____ inches of snow. |
15 |
On average, the water equivalent of 0 inches of snow is about ____ inches of water |
1 |
Radar gathers information about precipitation in clouds by measuring the: |
Amount of energy reflected back to a transmitter |
In a typical advancing winter storm, which of the following sequences of precipitation types is most likely to occur? |
Rain, freezing rain, sleet, and snow |
Freshly fallen snow ____ sound waves. |
Can absorb |
The main difference between a cloud drop and a raindrop is its: |
size |
A typical raindrop is about ____ a typical cloud droplet. |
One hundred times larger |
Saturation vapor pressure ____ as temperature increases. |
Increases |
Large cloud droplets fall faster than small cloud droplets because: |
Large drops have faster terminal velocity |
The lightest form of rain is: |
Drizzle |
The difference in saturation vapor pressure between supercooled water and ice reaches a maximum at about -2°C. This means that the ice crystal process will be most effective in producing precipitation when cloud temperatures are: |
Below -40 degrees Celsius |
Satellites measure rainfall from space using which instrument? |
Precipitation radar and the microwave imager |
Net convergence of air would cause surface pressure to ____ and net divergence would cause surface pressure to ____. |
decrease |
If the earth’s gravitational force were to increase, atmospheric pressure at the ground would: |
increase |
The surface pressures at the bases of warm and cold columns of air are equal. Which of the following statements is NOT correct? |
Pressure will decrease with increasing height at the same rate in both columns |
The surface pressures at the bases of warm and cold columns of air are equal. Air pressure in the warm column of air will ____ with increasing height ____ than in the cold column. |
Decrease; more slowly |
Suppose a parcel of air has a given temperature, pressure, and density. If the parcel’s size remains the same while its temperature increases, then the air pressure inside the parcel will: |
increase |
If two air parcels at sea level have the same size but different temperatures, the colder parcel of air will have: |
The same pressure but higher density than the warm parcel |
Which of the following relationships best describes the gas law? |
P=T x P x C |
If surface air pressure decreases, the height of the column in a mercury barometer would: |
decrease |
If the outside air temperature is 27°C and the air density is .2 kg/m3, the outside air pressure would be: |
172.28mb |
The scale on an altimeter indicates altitude, but an altimeter actually measures: |
pressure |
A barograph will: |
mark a continuous record of pressure on chart paper |
The unit of pressure most commonly found on a surface weather map is: |
A millibar or hectopascals |
If a liquid with a lower density than mercury were used in a barometer, the height of the column in the barometer would: |
increase |
An aneroid barometer works on the principle that: |
a small closed cell with most of its air removed will expand and contract with changes in air pressure |
Which of the following instruments measures pressure? |
barometer |
An aneroid barometer carried from sea level to the top of a 300 m (,000 ft) hill would indicate: |
Stormy weather |
The mercury barometer was invented by: |
Evangelista Torricelli |
To obtain the station pressure you must normally make corrections for: |
Temperature and gravity |
A station at an altitude of 900 m (about 3,000 feet) above sea level measures an air pressure of 930 mb. Under normal conditions, which of the values below do you think would be the most realistic sea level pressure for this station? |
1020 mb |
Suppose a station at sea level measures an air pressure of ,030 mb. Under standard conditions, what would be the most likely air pressure at an elevation of 600 m (about 2,000 ft) above this station? |
1090 mb |
To correctly monitor horizontal changes in air pressure, the most important correction for a mercury barometer is the correction for: |
altitude |
The surface weather map is a sea level chart. Thus, a surface weather map is also called: |
A constant height chart |
Lines connecting points of equal pressure are called: |
isobars |
Pressure changes: |
more rapidly in the vertical direction than in the horizontal |
On a weather map, ridges are: |
elongated high pressure areas |
Which of the following expresses the gas law? |
P=T x P x C |
According to the gas law, when temperature remains constant, which of the following is TRUE? |
P+ T rho C, rho 8 rho |
Suppose you are a pilot who is flying from warm air into colder air. In the cold air, even though your altimeter is still indicating the same altitude as it did in the warm air, you would be flying: |
Lower than your altimeter indicated |
On an isobaric surface, |
the atmospheric pressure is everywhere equal |
Low ____ on a constant height chart corresponds to low ____ on a constant pressure chart. |
Pressure; heights |
On a 500 millibar chart, ____ are drawn to represent horizontal changes in altitude which correspond to horizontal changes in pressure. |
Contour lines |
The contour lines drawn on a 500 mb chart are lines of constant: |
altitude |
If an airplane flies from standard temperature air into warmer than standard temperature air, without making any correction, the altimeter in the warmer air would indicate an altitude: |
Lower than the airplanes actual altitude |
Warm air aloft is associated with constant pressure surfaces that are found at ____ altitude than normal and ____ than normal atmospheric pressure aloft. |
Higher; higher |
On an upper-level chart, normally we find warm air associated with ____ pressure, and cold air associated with ____ pressure. |
High; low |
A surface low pressure center is generally associated with ____ on an upper level isobaric chart. |
A trough |
On an upper-level chart the wind tends to blow: |
Parallel to the isobars or contours |
A ridge on an upper-level isobaric chart indicates: |
Higher than average heights |
On an isobaric weather chart, the spacing of the height contours indicates the magnitude of the pressure gradient force. |
True |
Newton’s first law states that "an object at rest ____ as long as no force is exerted on the object." |
Will remain at rest |
During a reversible adiabatic process, the pressure gradient force is parallel to the isobars. |
False |
The Coriolis force is the force that causes the wind to blow. |
False |
The hydrostatic equation describes the equilibrium between the: |
vertical pressure gradient force and gravity |
Why is there a minus sign in the hydrostatic equation? (The hydrostatic equation is .) |
As pressure decreases, height increases |
The fundamental laws of motion were formulated by: |
Sir Isaac Newton |
The "force exerted on an object equals its mass times the acceleration produced" is a description of: |
Newtons Second Law |
Which of the following forces does not have a direct effect on horizontal wind motions? |
Gravitational force |
Which of the following can influence wind direction? |
coriolis force, pressure gradient, and centripetal force (all of these) |
Which of the following forces CANNOT act to change the speed of the wind? |
Coriolis force |
The net force on air moving in a circle at constant speed is: |
Inward toward the center of rotation |
The amount of pressure change that occurs over a given horizontal distance is called the: |
Pressure gradient |
Which of the statements below is NOT correct concerning the pressure gradient force? |
It is non-existent at the equator |
The pressure gradient force is directed from higher pressure toward lower pressure: |
At all places on earth |
The force that would cause a stationary parcel of air to begin to move horizontally is called the: |
Pressure gradient force |
Which of the following produces the strongest Coriolis force? |
Fast winds, high latitude |
The ____ is an apparent force created by the earth’s rotation. |
Coriolis force |
The rate of the earth’s rotation determines the strength of the: |
Coriolis force |
The Coriolis force is the result of: |
Rotating earth |
Which statement below is NOT correct concerning the Coriolis force? |
It causes the winds to blow faster |
If the earth stopped rotating which of the following would NOT be true? |
There would still be a Coriolis force |
A wind blowing at a constant speed parallel to straight line isobars with the pressure gradient force (PGF) and the Coriolis force in balance is called a: |
Geostrophic wind |
The net force acting on air which is blowing parallel to straight contours at constant speed is: |
0 |
Suppose that the winds aloft are geostrophic and blowing from the north. Low pressure is located to the: |
East |
Suppose that the winds aloft are geostrophic and blowing from the north. With the same orientation of isobars at the surface, the winds would blow from the: |
NorthWest |
The winds aloft in the middle latitudes would not blow from the west if: |
the air over high latitudes became warmer than over the equator |
If in the Northern Hemisphere the upper level winds above you are blowing from the south, then it is a good bet that a trough of low pressure is to the ____ of you. |
West |
When the wind blows in a more or less west to east direction, the wind flow pattern is called: |
Zonal |
A wind that blows at a constant speed parallel to curved isobars or contour lines is called a: |
Gradient wind |
If directly above you at 0,000 feet the wind is blowing from the south, then it is a good bet that at 0,000 feet, the center of lowest pressure is ____ of you, while the center of highest pressure is ____ of you. |
Right |
A wind flow pattern that takes on a more or less north-south trajectory is called: |
Meridional |
The vertical pressure gradient force is directed: |
Upward |
The winds aloft in the middle latitudes of the Southern Hemisphere generally blow: |
From west to east |
A surface LOW pressure area that moves from south to north directly east of your home would most likely produce winds that shift from: |
Northeast to north to northwest |
The wind around a surface low pressure center in the southern hemisphere blows: |
Clockwise and inward |
Surface winds blow across the isobars at an angle due to? |
The frictional forces |
If, at your home in the Northern Hemisphere, the surface wind is blowing from the northwest, then the region of lowest pressure will be to the ____ of your home. |
east |
Winds blow slightly inward: |
around surface low pressure centers in the Northern and Southern hemisphere |
Cyclonic flow means ____ in either the Northern or Southern Hemisphere. |
Circulation around a low pressure center |
Buys-Ballot’s law states that, "In the Northern Hemisphere if you stand with your back to the surface wind, then turn clockwise about 30°, lower pressure will be ____." |
To your left |
The wind around a surface high pressure center in the Northern Hemisphere blows: |
Clockwise and outward |
We can generally expect the air to be ____ above areas of surface low pressure and ____ above areas of surface high pressure. |
Rising; sinking |
The surface air around a strengthening low pressure area normally ____, while aloft, above the system, the air normally ____. |
Converges; diverges |
The atmosphere around the earth would rush off into space if the vertical pressure gradient force were not balanced by: |
gravity |
In the vertical, the pressure gradient force points ____ and gravity points ____. |
Away from the earth; toward the earth |
When the upward-directed pressure gradient force is in balance with the downward pull of gravity, the atmosphere is in: |
Hydrostatic equilibrium |
If an air parcel is completely at rest, which of the following forces can make the parcel begin to move? |
Pressure gradient |
The smallest scale of atmospheric motion is the: |
microscale |
An example of mesoscale motion is: |
Winds blowing through a city |
An example of microscale motion is: |
Winds blowing pas a chimney |
Which of the following associations is most accurate? |
Mesoscale- land breeze |
The slowing of the wind due to the random motion of air molecules is called |
Molecular viscosity |
Thermal turbulence above the surface is usually most severe: |
At the time of maximum surface heating |
On a clear, windy day, the depth to which mixing occurs above the surface depends upon: |
the wind speed, surface heating, and the landscape (all of the above) |
The top of the friction layer is usually found near what altitude? |
1,000m (3300 ft) |
The friction of fluid flow is called: |
viscosity |
The wind’s speed generally increases with height above the earth’s surface because: |
Friction with the earths surface slows the air near the ground |
The howling of wind on a blustery night is believed to be caused by: |
Eddies of higher air density |
An abrupt change in wind speed or wind direction is called |
Wind shear |
Violent, rotating eddies that create hazardous flying conditions beneath the crest of a mountain wave are called: |
rotors |
Clear Air Turbulence (CAT) can occur: |
When huge eddies develop in clear air |
Which below is NOT true concerning an "air pocket"? |
they often form in regions that exhibit strong vertical wind shear |
Pedaling a bicycle into a 20 knot wind will require about ____ as much effort as pedaling into a 0 knot wind. |
2 times |
The greatest wind speed ever recorded at the earth’s surface occurred at: |
231 mhp in 1934 on Mount Washington, New Hampshire |
Clear air turbulence often occurs near a boundary of high wind shear. |
True |
The size and shape of a turbulent eddy depend on |
the size of the obstacle, the shape of the obstacle, and the speed of the wind (all of these) |
If huge waves pound against the beach communities of Southern California for several days during clear, calm weather, it is a good bet that: |
the winds are strong somewhere over the Pacific ocean |
Suppose the wind speed increased from 5 mph to 25 mph. We can conclude that the force exerted by the wind increased by a factor of ____. |
5 |
Which of the features below could indicate prevailing wind direction? |
all of the above |
Dust storms and dust devils are ____ on Mars. |
found |
A wind rose indicates: |
the percentage of time that the wind blows from different directions. |
The most practical location for building a wind turbine would be: |
Regions with moderate, steady winds |
An offshore wind: |
Is wind blowing from land to water |
Which below would NOT be considered an onshore wind? |
Santa Ana wind |
A wind reported as 45° would be a wind blowing from the: |
northeast |
Suppose a west wind of 20 knots blows over a coastal region which is densely covered in shrubs. If this same wind moves out over the middle of a large calm lake, its speed and direction would probably be: |
Greater than 20 knots and more northwesterly |
What instrument would you use for a rawinsonde observation? |
Radiosonde balloon |
An instrument used to measure wind speed is called a(n): |
anemometer |
A wind reported as 225° would be a wind blowing from the: |
Southwest |
A wind profiler obtains wind information using: |
Doppler radar and the backscattered energy |
A wind instrument that usually consists of three or more cups: |
Cup anemometer |
The instrument that uses infrared or visible light in the form of a laser beam to determine wind direction is the: |
Iidar |
Which of the instruments below indicates both wind speed and wind direction? |
aerovane |
Which is NOT a characteristic of a thermal low? |
Becomes stronger with increasing height |
If the sea level pressure in Philadelphia, Pennsylvania is ,06 mb, the strongest summertime sea breeze along the New Jersey coast would occur when the sea level pressure just east of Atlantic City, New Jersey is: |
1019 mb |
During the summer in humid climates, nighttime clouds tend to form over water during a: |
Land breeze |
Which below is usually NOT true concerning a sea breeze circulation? |
They mainly occur at night |
A sea breeze circulation will reverse direction and become a land breeze: |
Once per day |
A sea or land breeze is caused by: |
Differences in temperature |
The nighttime counterpart of the sea breeze circulation is called a: |
land breeze |
In summer, during the passage of a sea breeze, which of the following is NOT usually observed? |
A drop in relative humidity |
A smog front is most often associated with which wind system? |
sea breeze |
A cool, summertime wind that blows from sea to land is called a: |
Sea breeze |
When a sea breeze moving north meets a sea breeze moving south, they form: |
cloudy conditions and showery weather over the land |
Clouds and precipitation are frequently found on the downwind side of a large lake. This would indicate that the air on the downwind side is: |
converging and rising |
During the summer along the coast, a sea breeze is usually strongest and best developed: |
In the afternoon |
Monsoon depressions are: |
low pressure areas that enhance rainfall during the summer monsoon |
The summer monsoon in eastern and southern Asia is characterized by: |
wet weather and winds blowing from sea to land |
An extremely strong downslope wind that occurs in parts of Antarctica would be considered a: |
Katabatic wind |
A katabatic wind on the Oregon coast would most likely blow from the: |
East to west downslope |
A katabatic wind is a ____, ____ wind. |
Cold, downslope |
A chinook wind in the Alps is called a: |
foehn |
The heat from a chinook wind is generated mainly by: |
Compressional heating |
A chinook wall cloud is a: |
Bank of clouds forming over the mountains |
On the eastern side of the Rocky Mountains, chinook winds are driest when: |
clouds form and precipitation falls on the upwind side of the mountains |
Chinook winds are: |
warm, dry winds that descend the eastern slope of the Rocky Mountain |
The main reason Santa Ana winds are warm is because: |
Sinking air warms by compression |
Santa Ana winds warm by ____ as the flow down an elevated desert plateau. |
Compression |
The Santa Ana wind is a ____, ____ wind that blows into southern California. |
Warm, dry |
Strong Santa Ana winds develop in Los Angeles during the fall when a ____ pressure center forms to the ____. |
High; northeast of Los Angeles over the Great Basin |
A warm, dry gusty wind that blows across North Africa is the: |
Leste |
Which of the following conditions favor the development of dust devils? |
Hot, dry days |
Another name for a small, rotating whirlwind observed at the surface is: |
Dust devil |
A dust or sandstorm that forms along the leading edge of a thunderstorm is a: |
haboob |
A northeaster along the east coast of the United States is best developed when a low pressure area: |
enhances the surrounding pressure gradient |
A sea breeze is most likely to develop along a coastline when: |
Large temperature differences exist between land and water |
Which of the following is a serious hazard to aircraft? |
Clear-air turbulence |
Good hang-gliding conditions require: |
Strong winds |
Strong winds blowing over vegetation results in: |
Brush fires |
If the wind speed doubles, the force exerted by the wind increases by a factor of ____. |
4 |
The land/sea breeze, lake breeze, and mountain/valley breeze are examples of: |
local winds |
A seiche can be caused by: |
strong winds and sudden changes in atmospheric pressure or by earthquakes |
A westerly wind means that the atmosphere: |
Is moving faster than the earth spins |
Which below is NOT an assumption of the single-cell model of the general circulation of the atmosphere? |
The earth rotates once in 24 hours |
The large thermally driven convection cell that is driven by convective "hot" towers along the equator is the ____. |
Hadley cell |
Air moving eastward more slowly than the earth rotates, would appear to be ____ wind to an observer on the earth. |
An east |
Chicago, Illinois (latitude 42°N) is located in the ____. |
westerlies |
The intertropical convergence zone (ITCZ) is a region where: |
northeast trades meet the southeast trades |
In terms of the three-cell model of the general circulation, areas of surface low pressure should be found at: |
The equator and 60 degrees latitude |
In Honolulu, Hawaii (latitude 2°N), you would most likely experience winds blowing from the: |
northeast |
At Barrow, Alaska (latitude 70°N), you would expect the prevailing wind to be: |
easterly |
At Barrow, Alaska (latitude 70°N), you would expect the prevailing wind to be: |
easterly |
Generally, along the polar front, one would not expect to observe: |
Sinking air aloft |
According to the three-cell general circulation model, at the equator we would not expect to find: |
A ridge of high pressure |
The wind belt observed on the poleward side of the polar front is called the: |
Polar easterlies |
On a weather map of the Northern Hemisphere, one would observe the westerlies: |
Between the subpolar lows and the subtropical highs |
The majority of the United States lies within which wind belt? |
westerlies |
On a weather map of the Northern Hemisphere, the trade winds would be observed: |
South of the subtropical highs |
In the general circulation of the atmosphere, one would find the region called the doldrums: |
At the equator |
In terms of the three-cell general circulation model, the driest regions of the earth should be near: |
30 degrees latitude and the polar regions |
The world’s deserts are found at 30° latitude because: |
Of the sinking air of the subtropical highs |
On a surface weather map during the month of July, one would expect to find what type of pressure system over the desert southwest of the United States? |
Thermal low |
The semi-permanent pressure systems associated with the polar front are called: |
Subpolar lows |
Which of the following is not considered a semi-permanent high or low pressure area? |
Siberian high |
The position of the Pacific high over the North Pacific Ocean shifts ____ in winter and ____ in summer. |
Southward; northward |
The large semi-permanent surface anticyclone that is normally positioned over the ocean, west of California, is called the: |
Pacific high |
A thermally direct cell is one that: |
Is driven by the energy from the sun |
Many small-scale processes are ____ in General Circulation Models. |
Approximated and parameterized |
Which of the following does NOT describe the subtropical jet stream? |
Forms along the polar front |
Which below does NOT describe the polar front jet stream? |
is normally found at a higher elevation than the subtropical jet |
In the Northern Hemisphere, the polar jet stream is strongest when: |
air north of the polar front is much colder than air south of the polar front. |
The jet stream flows: |
in a wavy pattern from west to east |
As an air parcel aloft moves northward from the equator, it moves closer to the earth’s axis of rotation. Because of the conservation of angular momentum, the air parcel’s motion should: |
Increase in speed |
In the Northern Hemisphere, air found to the north of the polar front is ____, while air further south is ____. |
Cold; warm |
The average winds aloft are strongest in: |
winter |
The low-level jet that forms over the Central Plains of the United States appears to be responsible for: |
Nighttime thunderstorms |
Factors that contribute to the formation of a low-level jet stream over the Central Plains of the United States are: |
the sloping of the land from the Rockies to the Mississippi Valley, a north-south trending mountain range, stable air above the jet ( all of these) |
Which below is NOT correct about the stratospheric polar-night jet stream? |
it is found near the tropopause. |
Generally, on an upper-level (00 mb) chart in the Northern Hemisphere during July, we would expect to find the tropical easterly jet stream: |
south of the upper-level subtropical high |
A phenomenon in the Atlantic Ocean, similar to the southern oscillation, is the: |
North Atlantic Oscillation |
Average winter temperatures in Great Britain and Norway would probably be much colder if it were not for the: |
North Atlantic Drift |
In the Northern Hemisphere, ocean currents in the Atlantic and the Pacific move in a generally circular pattern. The direction of this motion is ____ in the Atlantic and ____ in the Pacific. |
Clockwise; clockwise |
The Pacific Decadal Oscillation is similar to the El Niño/Southern Oscillation, except that it: |
Affects the fish populations |
At any given time, only one jet stream can be found in the atmosphere. |
FALSE |
The cold water observed along the northern California coast in summer is due mainly to: |
Upwelling |
Major ocean currents that flow parallel to the coast of North America are: |
California, Gulf stream, Labrador |
The name given to the current of warm water that replaces cold surface water along the coast of Peru and Ecuador during December is: |
El Nino |
The two ocean currents, warm and cold, that produce fog off the coast of Newfoundland are the: |
Gulf Stream and Labrador current |
The turning of water with depth is known as: |
The Ekman Spiral |
The Ekman Spiral describes: |
The turning of water with depth |
Upwelling is: |
The rising of cold water from below |
During a major El Niño event, |
extensive ocean warming occurs over the tropical Pacific |
At jet streak is a place where ____ is (are) often found. |
clear air turbulence, strong vertical wind speed shear, very strong winds (all of these) |
Upwelling occurs along the northern California coast because: |
winds cause surface waters to move away from the coast |
A condition where the central and eastern tropical Pacific Ocean turns cooler than normal is called: |
La Nina |
The reversal of the positions of surface high and low pressure at opposite ends of the Pacific Ocean is called: |
The southern oscillation |
If the earth’s surface was homogeneous (either all land or all water), |
the semipermanent highs and lows wouldnt change in intensity |
Because clouds often block their view, instruments onboard satellite cannot regularly make observations of surface winds. |
False |
The scatterometer measures winds by sending and receiving pulses of: |
Microwave energy |
Satellites provide a global picture of winds by converting ____ into wind speed and direction. |
Sea roughness |
During some years, the northern hemisphere has more than 0 semi-permanent highs and lows. |
false |
The southern hemisphere has ____ semi-permanent lows than the northern hemisphere. |
fewer |
Areas of rising air tend to be associated with ____ precipitation. |
abundant |
Jet streams sometimes split into two branches. |
TRUE |
A jet stream transfers more heat across the globe when it is: |
meridional |
The ultimate cause of jet streams is: |
The energy imbalance between high and low latitudes |
During the positive phase of the North Atlantic Oscillation, |
an increased pressure gradient exists across the North Atlantic Ocean, the prevailing westerlies in the northern hemisphere are stronger, winters in the eastern US are wet and mild, (all of these) |
A good source region for an air mass would be: |
generally flat areas of uniform composition with light surface winds |
The origin of cP and cA air masses that enter the United States is: |
Northern Canada and Alaska |
Continental polar (cP) and continental Arctic (cA) air masses: |
originate over the ice- and snow-covered regions of the arctic, northern Canada, and Alaska where long, clear nights allow for strong radiational cooling of the surface. |
Which of the following statements is most plausible? |
In winter cA source regions have lower temperatures than cP source regions |
The temperature that unsaturated air would have if it moved from its original altitude to a pressure of ,000 mb is the: |
Potential temperature |
In an exceptionally cold winter during which the Great Lakes were entirely covered by ice, lake effect snows would be expected in extremely high frequency and intensity. |
FALSE |
Compared to an mP air mass, mT air is ____. |
Warmer and moister |
A moist, tropical air mass that is warmer than the surface over which it is moving would be classified ____. |
mT |
The greatest contrast in both temperature and moisture will occur along the boundary separating which air masses? |
mT and cP |
An air mass is characterized by similar properties of ____ and ____ in any horizontal direction. |
Temperature; moisture |
One would expect a cP air mass to be: |
Cold and dry |
A Texas norther (or blue norther) is most often associated with which air mass? |
cP |
When cP air moves into western Washington, western Oregon, and California from the east, the air mass is warmer at the surface than it was originally because: |
The air sinks, is compressed, and warms |
Which air mass would show the most dramatic change in both temperature and moisture content as it moves over a large body of very warm water? |
Continental polar (cP) in winter |
The coldest of all air masses is ____. |
cA |
What type of air mass would be responsible for refreshing cool, dry breezes after a long summer hot spell in the Central Plains? |
cP |
Clear sunny days with very cold nights would be associated with what type of air mass? |
cP |
Cumuliform cloud development would be most likely in which of the following? |
cP air mass moving over warm water |
Lake-effect snows are best developed around the Great Lakes during: |
late fall and early winter when cold, dry polar air moves over the relatively warm water |
The lake effect occurs when ____ air mass moves over a ____ body of water. |
cP; warm |
Generally, the greatest lake effect snow fall will be on the ____ shore of the Great Lakes. |
eastern |
During the winter, an air mass that moves into coastal sections of Oregon and Washington from the northwest would most likely be ____. |
mP |
Wintertime mP air masses are less common along the Atlantic coast of North America than along the Pacific coast mainly because: |
The prevailing winds aloft are westerly |
The designation for a cool, moist air mass is ____. |
mP |
What type of air mass would be responsible for snow showers on the western slopes of the Rockies? |
mP |
What type of air mass would be responsible for persistent cold, damp weather with drizzle along the east coast of North America? |
mP |
What type of air mass would be responsible for hot, muggy summer weather in the eastern half of the United States? |
mT |
The air mass with the highest actual water vapor content is ____. |
mT |
In Southern California, which air mass is mainly responsible for heavy rains, flooding in low-lying valleys, and melting of snow at high elevations? |
mT |
During the spring, which air mass would most likely bring record-breaking high temperatures to the eastern half of the United States? |
mT |
What type of air mass would be responsible for daily afternoon thunderstorms along the Gulf Coast? |
mT |
What type of air mass would be responsible for heavy summer rain showers in southern Arizona? |
cT |
An mT air mass lying above a cold ground surface represents a(n) ____ situation. |
stable |
What type of air mass would be responsible for summer afternoon thunderstorms along the eastern slopes of the Sierra Nevada Mountains in California? |
mT |
Which air mass forms over North America only in summer? |
cT |
What type of air mass would be responsible for hot, dry summer weather in southern Arizona? |
cT |
A maritime polar air mass that reaches the Pacific Coast is: |
Cool, Moist, and Conditionally Unstable |
During winter, easterly winds along the front range of the Rocky Mountains provide excellent conditions for: |
Upslope snow |
Along the boundary between continental polar and maritime tropical air masses, ____ is often found. |
Widespread precipitation and storms |
On a weather map, the transition zone between two air masses with sharply contrasting properties is marked by: |
A front |
The word "frontogenesis" on a weather map would mean that: |
A front is regenerating or strengthening |
Continental tropical air masses are typically found in: |
northern Mexico and the southwestern US |
Fronts are associated with: |
Low pressure |
The only indication on the station model of past weather conditions is the: |
temp |
A drylines is: |
a dew point front and a boundary marking a strong horizontal change in atmospheric moisture |
An upper-air front involves downward motion of the: |
tropopause |
When comparing an "average" cold front to an "average" warm front, which of the following is NOT correct? |
generally, precipitation covers a much broader area with a cold front |
Alternating lines of blue and red on a surface weather chart indicate: |
A stationary front |
A stationary front does not move because: |
The wind blows parallel to the front |
A true cold front on a weather map is always: |
Followed by cooler air |
Which of the following is NOT correct concerning a cold front? |
It is colored purple |
On a weather map, this front, drawn in blue, represents a region where colder air is replacing warmer air: |
cold front |
Before the passage of a cold front the pressure normally ____, and after the passage of a cold front the pressure normally ____. |
rises |
Squall lines most often form ahead of a: |
cold front |
In winter, thunderstorms are most likely to form along: |
cold fronts |
A "back door" cold front moving through New England would most likely have winds shifting from ____ to ____. |
East; west |
A "back door" cold front describes which of the following situations? |
a cold front that moves into New England from the Atlantic Ocean |
A cold front that moves into New England from the east or northeast is called: |
A "back door" cold front |
Which of the following is NOT correct concerning a warm front? |
it has warm air ahead (in advance) of it |
A halo around the sun or moon indicates that rain may be on the way because the halo indicates: |
A warm front may be approaching |
A frontal inversion would probably be best observed: |
With a warm front in winter |
In winter, which sequence of clouds would you most likely expect to observe as a warm front with precipitation approaches your location? |
cirrus, cirrostratus, altostratus, nimbostratus |
The rising of warm air up and over cold air is called: |
overrunning |
At a warm front, the warm air: |
rises and cools |
During the winter as you travel toward a warm front, the most likely sequence of weather you would experience is: |
Snow, sleet, freezing rain, rain |
On a weather map where cold air is replacing cool air, what type of front is drawn? |
Cold-type occluded front |
Occluded fronts may form as: |
A cold front overtakes a warm front |
A cold-type occluded front: |
Has cold surface air behind it |
What type of weather front would be responsible for the following weather forecast? "Increasing cloudiness and warm today with the possibility of showers by this evening. Turning much colder tonight. Winds southwesterly becoming gusty and shifting to northwesterly by tonight." |
cold front |
What type of weather front would be responsible for the following weather forecast? "Increasing high cloudiness and cold this morning. Clouds increasing and lowering this afternoon with a chance of snow or rain tonight. Precipitation ending tomorrow morning. Turning much warmer. Winds light easterly today becoming southeasterly tonight and southwesterly tomorrow." |
cold front |
What type of weather front would be responsible for the following weather forecast? "Cool today with rain becoming heavy by this afternoon. Slightly warmer tomorrow. Winds southeasterly becoming westerly to northwesterly by tomorrow morning." |
cold front |
What type of weather front would be responsible for the following weather forecast? "Light rain and cold today with temperatures just above freezing. Southeasterly winds shifting to westerly tonight. Turning colder with rain becoming mixed with snow, then changing to snow." |
cold-type occluded front |
The polar front theory of a developing wave cyclone was conceived in: |
Norway |
Which of the scientists below was not one of the meteorologists who helped develop the polar front theory of a developing wave cyclone? |
C.G Rossby |
On a surface weather map that shows an open wave cyclone, the warm sector can be observed: |
Ahead of the advancing cold front |
According to the model of the life cycle of a wave cyclone, the storm system is normally most intense: |
When the system first becomes occluded |
Which below is not a name given to a large cyclonic storm system that forms in the middle latitudes? |
anticyclone |
In the polar front theory of a developing wave cyclone, energy for the storm is usually derived from all but which of the following? |
Heat energy stored in the ground |
Another term for explosive cyclogenesis used by meteorologists is: |
bomb |
The development or strengthening of a middle latitude storm system is called: |
cyclogenesis |
Which region is not considered to be a region where cyclogenesis often occurs? |
california |
A building anticyclone means: |
The central pressure is increasing |
For cyclogenesis to occur along a frontal wave, the winds aloft directly above the wave should be: |
diverging |
The piling up of air above a region is called: |
convergence |
If the flow of air into a surface low pressure area is greater than the divergence of air aloft, the surface pressure in the center of the low will: |
increase |
Which of the following is NOT associated with rising air motions? |
convergence of air aloft |
Cyclogenesis is the ____ of a mid-latitude cyclone. |
Development or strengthening |
A lee-side low forms: |
On the downwind side of a mountain |
Northeasters (or nor’easters) are midlatitude storms commonly found: |
Along the Atlantic coast of North America |
A surface low pressure area with a deep upper-level trough to the west will tend to move toward the: |
northeast |
When a deep upper-level trough is located to the east of a surface anticyclone, the surface anticyclone will tend to move toward the: |
southeast |
When an upper-level low lies directly above a surface low, |
The surface low will probably weaken |
An upper-level pool of cold air that has broken away from the main flow is called: |
a cut-off flow |
For a surface storm system to intensify, the upper-level low (or trough) should be located to the ____ of the surface low. |
west |
Developing low pressure areas generally have ____ air near the surface and ____ air aloft. |
converging, diverging |
Strong storms that develop over water, poleward of the polar front, are called: |
polar lows |
Like hurricanes, polar lows have a clear area in their center. |
true |
When upper-level divergence of air above a surface low pressure area is stronger than the convergence of surface air, the surface pressure will ____ and the storm itself will ____. |
decrease, intensify |
If the outflow of air around a surface high pressure area is greater than the convergence of air aloft, you would observe: |
a decrease in the central pressure |
Longwaves in the middle and upper troposphere usually have lengths on the order of: |
thousands of kilometers |
An upper-level trough that shows retrograde motion would probably be moving toward the: |
west |
Rossby waves are also known as: |
longwave |
Atmospheric shortwaves usually move ____ at a speed that is ____ than longwaves. |
west to east, faster |
Atmospheric shortwaves usually move ____ than longwaves, and ____ when they move through a longwave ridge. |
faster, weaken |
A small, moving disturbance imbedded in a longwave is called: |
a shortwave |
On an upper-level chart where the isotherms cross the isobars (or contours) and temperature advection occurs, the atmosphere is called: |
baroclinic |
During baroclinic instability, |
wave cyclones can intensify into large storm systems, strong wind speed shear exists from the surface up to at least the 500 mb level, rising and descending air motions exist, temperature advection is occurring (all of these) |
Which of the following statements is NOT correct about vorticity? |
the earths vorticity is zero at the poles |
If we assume that the absolute vorticity of flowing air is conserved, air moving northeastward will bend ____ to compensate for the ____ in the earth’s vorticity. |
anticyclonically ; increase |
Lee-side lows are: |
storms (extratropical cyclones) that form on the eastern (lee) side of a mountain range |
The planetary vorticity of an air parcel moving from low toward high latitude in the Northern Hemisphere will: |
increase |
Vorticity refers to: |
The spin of air parcels |
The type of weather system known as a ‘mid-latitude cyclone’ CANNOT form over the tropical ocean because: |
surface temperature contrasts are not large and the Coriolis force is weak in the tropics |
MET1010
Share This
Unfinished tasks keep piling up?
Let us complete them for you. Quickly and professionally.
Check Price