Geog 1900 Exam 3 Dr. Mark

Which of the following best explains why sea breezes usually do not occur during winter?

The land is usually colder than adjacent water during winter. ea breezes tend to be strongest in the spring and summer, when the greatest daytime temperature contrasts occur between land and sea.

According to the Ekman spiral, in what direction does the surface layer of ocean water move, relative to the overlying wind?

45 degrees to the right of the wind in the Northern Hemisphere. According to the Ekman spiral, the surface water moves not in the same direction as the wind, but at an angle of 45 degrees to the right of the air flow in the Northern Hemisphere and to the left in the Southern Hemisphere.

If you observe short, intense, scattered rainfall as a front passes, which of the following are you most likely to be experiencing?

A cold front. The air ahead of a cold front tends to be unstable and therefore easily lifted. This promotes development of cumuliform clouds along these boundaries. With their large vertical extent, cumuliform clouds can often produce intense precipitation. However, because of the limited horizontal extent and rapid movement of the frontal wedge, such precipitation is often of short duration.

Which of the following best defines an air mass

A large body of air with similar temperature and moisture characteristics

Which of the following best defines a front?

A narrow boundary separating different air masses

What conditions can one expect when the Indian monsoon takes place during the summer?

A reversal in wind direction at high and low levels of the atmosphere. During late spring or early summer, heating of the Indian subcontinent contributes to a reversal in the wind direction at both low and high levels of the atmosphere.

Which of the following best describes a single, extremely powerful and complex storm with updrafts and downdrafts bending and wrapping around each other due to strong wind shear?

A supercell storm, Despite their single-cell structure, supercell storms are remarkably complex, with the updraft and downdraft bending and wrapping around each other due to strong wind shear.

What does a tornado watch mean?

A tornado is possible.

Which of the following best describes the vast majority of lightning on Earth?

Cloud-to-cloud lightning. About 80 percent of all lightning results from the discharge of electricity within clouds, as opposed to discharge from cloud-to-ground. This cloud-to-cloud lightning occurs when the voltage gradient within a cloud, or between clouds, overcomes the electrical resistance of the air

Which of the following is the coldest type of air mass?

Continental Arctic

What is the name for an air mass that forms over a large, high-latitude landmass with very low temperatures?

Continental Polar

Which of the following best describes the extremely hot, dry, and often cloud-free air masses that form during the summer over hot, low-latitude areas?

Continental Tropical air masses

Cold fronts-Cloud

Cumuliform clouds, often producing intense precip, rapid movement, short lived storms

Which of the following best describes the strong downdrafts associated with mesoscale convective systems that can produce very powerful, larger-scale horizontal winds?

Derechos, Such winds may last for hours and achieve speeds higher than 120 mph.

Under clear conditions, when would the wind on a mountain be most likely to flow toward the peak?

During the day, mountain slopes oriented toward the Sun heat most intensely. The air over these sunny slopes warms, expands upward, and diverges outward at higher altitudes. The valley breeze occurs when air flows up from the valleys to replace it.

Which of the following best describes a circulation involving rising air near the equator and sinking air in the subtropics?

Hadley Cell

Which circulation cell extends from the equator to the subtropics?

Hadley cell

Which of the following types of weather are NOT typically associated with anticyclones?

Heavy precipitation

In which of the following areas is cyclogenesis most likely to occur?

In regions of strong temperature contrasts

Warm Fronts-cloud

as warm air rises, nimbostratus (rain/storm), alto stratus, cirrostratus abd cirrus occur

Which of the following descriptions is most appropriate for a thunderstorm that occurs far from a frontal boundary?

It is an air mass thunderstorm, the most common and least destructive of thunderstorms. Air mass thunderstorms are very localized and are well removed from frontal boundaries.

Which of the following describes meandering rivers of air 9 to 12 km above sea level with wind speeds averaging 180 km per hour in winter?

Jet Streams can be thought of as meandering rivers of air, usually 9 to 12 km above sea level. Their wind speeds average about 180 km/hr in winter and about half that in summer, though peak winds can exceed twice these values.

Semi-Permenant Cell

Large area of high or low pressure present year after year, size and location change seasonally

ocean gyres

Large, circular ocean circulation cells that form around sub tropic high pressure zones

What is the name for an air mass that develops over warm tropical waters and is warm, moist, and unstable near the surface?

Maritime Tropical

Which of the following air mass types generally has the highest dew point?

Maritime Tropical

Which of the following best describes midlatitude cyclones that move along the U.S. East Coast and bring moist maritime air towards New England, often producing cold winds and heavy snowfall in winter?

Northeasters

Where is this pressure cell located?

Northern Hemisphere, surface

In classical cyclogenesis, what is the last stage in the life of a midlatitude cyclone in North America?

Occlusion

The Tibetan low of southern Asia is an example of which of the following?

Semipermanent cells of high and low pressure are called semipermanent because they undergo seasonal changes in position and intensity over the course of the year. In summer, the best-developed cells are the Hawaiian and Bermuda-Azores highs of the Pacific and Atlantic Oceans and the Tibetan low of southern Asia.

Santa Ana winds

Specific to Cali, common in fall, occur in response to large area of high pressure, causing air to flow out of the rockies

Which of the following best describes the scale at which cyclones, anticyclones, troughs, and ridges, covering hundreds or thousands of square kilometers, occur?

Synoptic Scale

Why are tornadoes most common during spring and early summer in most areas of the United States?

The contrasts between air masses are at their greatest.

The theory postulated in the early part of the twentieth century to describe the formation, development, and dissipation of midlatitude cyclones is known as which of the following?

The polar front theory

Which of the following describes a recurrent event in which sea surface temperatures in the tropical eastern Pacific are significantly above normal?

Unusually warm waters in the eastern Pacific Ocean mark an El Niño event.

Which of the following best describes the phenomenon that typically develops at the surface beneath an area of divergence in the upper atmosphere?

Upper-level divergence causes a low pressure system, whereas upper-level convergence causes high pressure at the surface.

Air masses are classified according to the latitude of their source regions: tropical, polar, or arctic. How else are air masses classified?

Whether they form in a continental (dry) or maritime (moist) source region

Which of the following best describes winds blowing from east to west or from west to east?

Zonal

Katabatic Winds

cold over snow covered plateau/high areas. slide off and down hill. along Antartic and greenland ice sheets

Isobars

line connecting points of equal pressure, PGF acts perpendicular to isobar

Isotherms

line connecting points of equal temperature, temp gradients perpendicular to isotherm

stationary front

non moving boundary, can present significant flooding, divides warm and cold air masses

Tornado

rotating column of air w/ extreme horizontal winds

overrunning

warm air flows upward along the boundary when cold front moves in

occluded front

warm air mass closed off from and not in contact with surface. occur when faster moving cold front catches up with warm front

Chinook winds

warmed by compression, descend eastern slopes of rockies, low pressure

dryline

where mT and cT reside next to each other, forming as warm moist air migrates westward to the drier air. increase temp and decreases dew point

upwelling

wind out of figure, horizontal current to east

Foehn wind

winds that flow down mountain slopes, warm by compression, introduce hot, dry and clear conditions to lowlands