Relative humidity in cities is usually _____ compared to rural areas. |
|
lower |
| |
What is the basic reason why condensation is not very important in causing a cloud droplet to grow to raindrop size? |
|
condenation is too slow |
| |
Dew point is the temperature at which water vapor in the air begins to condense. The temperature inside a cloud would therefore be... |
|
about equal to the dew point |
| |
The _______ cloud may have an "anvil head" |
|
cumulonimbus |
| |
A ________ consists of two compartments each capable of holding 0.025 cm of water. |
|
tipping-bucket gauge |
| |
When warm moist air moves over a cold surface, _______ fog may result. |
|
advection |
| |
Clouds, dew, and frost all form because air has become saturated. This condition of saturation is usually caused by... |
|
the air being cooled |
| |
If ice crystals form in this cloud, they will experience the cloud environment as having a relative humidity of... |
|
more than 100% |
| |
A halo around the Sun or Moon indicates the cloud _______ is present. |
|
cirrostratus |
| |
The necessary conditions for hail formation include strong upward vertical motion and... |
|
large numbers of supercooled droplets |
| |
Of the following cloud types, which is most likely to produce the most rain? |
|
nimbostratus |
| |
A cloud type that develops as a consequence of local convection is... |
|
cumulus |
| |
A wintertime form of precipitation that consists of small ice particles is called... |
|
none of these |
| |
The most common way for air to be cooled in order that a cloud may form is by... |
|
rising and expanding |
| |
Freezing rain (ice storm) or sleet occurs when... |
|
upper air is warm and surface air is cold |
| |
Which type of cloud is most likely to form a halo around the Sun or Moon? |
|
cirrostratus |
| |
This cloud sometimes produces mare's tails. |
|
cirrus |
| |
This growth from cloud droplet to raindrop occurs mainly because of... |
|
collision and coalescence |
| |
The intensity of rainfall can be calculated with data from a... |
|
weighing gauge |
| |
The cloud form that is best described as sheets or layers that cover much or all of the sky is termed: |
|
alto |
| |
Wind speeds in the city, compared to rural areas, are... |
|
about 25% less |
| |
Why are high altitude clouds always so thin? |
|
very little water vapor is present |
| |
A cumulus cloud is recognized mainly by its... |
|
obvious vertical dimension |
| |
Atmospheric electricity is believed to play an important role in... |
|
collision-coalescence process |
| |
This fog results from adiabatic cooling |
|
none of these (upslope) |
| |
The ______ may result in snow or rain. |
|
Bergeon process |
| |
The word 'radiation' in the term radiation fog refers to... |
|
radiant energy lost by the ground |
| |
Supercooled water is water which is... |
|
still liquid at temperatures below 0degreeC |
| |
In order for water condensation to occur, |
|
a and b |
| |
Clouds are classified and named according to their altitude and... |
|
form or appearance |
| |
Clouds that form in air that is very stable will usually be... |
|
stratus |
| |
Which one of the fogs listed below may be categorized as an evaporation fog? |
|
steam fog |
| |
The conditions that persist along the West Coast of the US that are conducive to fog formation are, |
|
moist air moving over a cold surface |
| |
Clouds and precipitation form in the air primarily due to... |
|
air being cooled as it rises |
| |
Which of the following is not generally true of urban climates? |
|
higher relative humidity |
| |
One aspect of the _______ theory relies on the fact that different-sized cloud droplets fall at different speeds. |
|
collision-coalescence process |
| |
Which of the following does not contribute to urban-induced precipitation increases? |
|
higher relative humidity in cities |
| |
Thunder and lightning are associated with the _______ cloud. |
|
cumulonimbus |
| |
A _______ is a layer of dark gray clouds that produces precipitation. |
|
nimbostratus |
| |
The formation of raindrops by collision and coalescence of smaller cloud droplets is strongly inflenced by... |
|
electrical charges on the droplets |
| |
Clouds which have extensive vertical dimensions are... |
|
cumulus |
| |
The most common source of cloud condensation nuclei is... |
|
combustion by-products (pollution) |
| |
Condensation nuclei may be formed from... |
|
all of the above |
| |
The _______ makes use of a spring balance. |
|
weighing gauge |
| |
A ________ magnifies rainfall ten times. |
|
standard rain gauge |
| |
"Anvil head" is a term applied to: |
|
cumulonimbus clouds |
| |
The most important process for cloud formation in the atmosphere is... |
|
cooling by expansion of the air |
| |
This fog is found in valleys at night and in the early morning: |
|
radiation fog |
| |
Cumulus clouds... |
|
all of these |
| |
The water content or volume of a raindrop is approx. ____ times that of a typical cloud droplet. |
|
1 million |
| |
The cloud droplets in a cloud are formed by water vapor molecules and... |
|
condensation nuclei |
| |
Dew is most likely to form on... |
|
clear calm nights |
| |
Hail is most commonly associated with... |
|
cumulonimbus clouds |
| |
The _______ cloud is confined to the middle height range. |
|
altostratus |
| |
Hail suppression: |
|
relies primarily on cloud seeding with silver iodine |
| |
Pollutants may: |
|
all of the above |
| |
The important difference between liquid droplets and ice crystals in a supercooled cloud is that ice crystals... |
|
grow much more rapidly |
| |
Cloud seeding is used: |
|
in all of the ways listed above |
| |
Which of these is a mid-level cloud? |
|
none of these |
| |
The process by which a cloud droplet first forms is |
|
condensation |
| |
Fog is usually a result of an air having been... |
|
either a) or c) |
| |
Why do clouds represent a source of heat for the atmosphere? |
|
cloud formation releases latent heat to the air |
| |
This method of frost prevention relies heavily on the release of latent heat of fusion: |
|
sprinklers |
| |
Which of these clouds is least likely to produce precipitation that reaches the ground? |
|
cirrostratus |
| |
Cloud seeding experiments have yielded the result of... |
|
all of the above |
| |
Freezing nuclei are part of the... |
|
Bergeon process |
| |
Cloud seeding with silver iodine is based on the... |
|
Bergeon process |
| |
On which day of the week would someone living in or downwind of a city expect the least precipitation ( on averagre)? |
|
Sunday |
| |
The _______ is associated with supercooled clouds. |
|
Bergeon process |
| |