Weather Flashcards
(90 cards)
1
Q
What is the driving force behind weather
A
The Sun
2
Q
What causes the air currents
A
As solar energy reaches the Earth, equatorial region regions heat up more than the poles, which causes the air there to rise
, drawing air in from cooler areas elsewhere
3
Q
What creates low pressure
A
Heated rising air
4
Q
What creates wind?
A
Air flowing form areas of higher pressure (cooler with air sinking) to lower pressure areas created when heated air rises
5
Q
What creates high pressure?
A
Cooler air falling
6
Q
Wind is created by air flowing form ______ to _____
A
highs (high pressure) to lows (lower pressure)
7
Q
Evaporation
A
Water vapor rising into the atmosphere
8
Q
Condensation
A
The changing of water from a vapor to a liquid
9
Q
Precipitation
A
Ay form of water falling from the sky such as rain, sleet, snow, and hail
10
Q
Barometric pressure
A
The pressure of the atmosphere
11
Q
The terms high and low pressure indicate
A
The pressures relative to the surrounding areas
12
Q
High and Low Pressures resultfrom
A
Vertical airflow caused by changed in temperature
13
Q
Air pressure is measured with
A
A barometer
14
Q
Isobars are
A
Lines of equal pressure
15
Q
Due to the counterclockwise circulation around low pressure areas in the Northern Hemisphere, cold air will likely be found to the _____ and _____ of low pressure areas
A
north and west
16
Q
Due to the counterclockwise circulation around low pressure areas in the Northern Hemisphere, warm air is most often found to the _______ and ____ of low pressure areas
A
south and east
17
Q
Define Front
A
a boundary between two air masses with an abrupt pressure and temperature across it.
18
Q
Warm Front
A
red line and half circles
19
Q
cold front
A
blue line and triangles
20
Q
occluded front
A
purple with half-circles and triangles on the same side
21
Q
stationary front symbols on a map are
A
red half circles on one side, blue triangles on the other
22
Q
What is a cold front?
A
a warm-cold air boundary with the colder air replacing the warmer denoted on a weather map with a blue line with triangles pointing the direction the cold air is moving
23
Q
As a cold front moves into an area
A
the heavier cool air pushes under the lighter, warm air it is replacing
24
Q
As the warm air rises,
A
it cools and if the rising air is humid enough, water vapor in it will condense into clouds and maybe precipitation
25
A Warm Front is
the boundary between warm and cool, or cold, air when the warm air is replacing the cold air
26
Warm fronts often bring
days of inclement weather
27
The warm front symbol on a weather map marks
the warm-cold boundary at the Earth's surface
28
On a weather map a warm front is indicated by
red half-circles pointing in the direction the warm air is morbing
29
Where is the warm-cold boundary in a warm front
over the cold air, and can stretch hundreds of miles.
30
Warm fronts tend to form
to the east of low pressure centers where southerly winds push warm air northward
31
Occluded front is caused by
A cold front overtaking a warm front
32
An occluded front is shown on a weather map symbolically as
a line with purple triangles and half circles on the same side
33
A frontal occlusion often occurs
in the later stages of a storm's life cycle when the air in the warm sector of the storm is lifted off the ground
34
A cold occlusion happens when
the air behind the storm front is colder than the air ahead of the storm from. The coldest air undercuts the cool air ahead of the front and the occluded front acts very similar to a cold front
35
A warm occlusion occurs when
the air behind the front is warmer than the air ahead of the front. The cool air is lighter than the coldest air ahead of the front so the cool air rises up and over the coldest air at the surface and the occluded front acts very similar to a warm front
36
An occluded front has well-defined
vertical boundaries between the coldest air, the cool air and the warm air
37
Stationary Front
A cold front is the boundary between cool and warm air when the cool air is replacing the warm. A warm front is the boundary when the warm air is replacing the cold air. When the pushing is a standoff, you have a stationary front.
38
Stationary front map symbol
combining both the warm front and cold front symbols, you have a line with blue tringles (cold) on one side and red half-circles (warm) on the other
39
A trough is
An elongated area of low atmospheric pressure that can occur at the Earth's surface or higher altitudes.
40
Precipitation tends to fall ___ of the trough axis while _____, ______ air tends to prevail to ________of the trough
east, cooler, drier, west
41
Air rises ___ of troughs and sinks ____ of troughs
East, Weat
42
Upper-level troughs influence
many surface weather features, including the movement of surface low pressure areas, clouds and precipitation
43
A ridge is
an elongated area of high atmospheric pressure
44
Ridges occur
both at the Earth's surface and at higher altitudes
45
Sunny, dry weather usually prevails to the ____ of the upper level ridge while on the ___ of the ridge, wet weather can dominate
east, west
46
Air tends to ___ east of ridge axis inhibiting clouds and precipitation
sink
47
air tends to rise to the ____ of the ridge axis, which can lead to the formation of clouds and precipitation
west
48
Sea breezes form
because water heats up much slower than land. The land heats up, warms the air close to the ground, which rises. Cool air from the ocean moves in to replace the rise warmer air, which may create an on shore wind.
49
The strength of a sea breeze is relative to
the temperature contrast between the air temperature inland and the ocean temperature
50
A land breeze is made
by the temperature difference between the quickly cooling land and slowly cooling water. As the land cools, it cools the surrounding air, which moves offshore to replace the warm air over the much more slowly cooling ocean. This is most common during the fall and winter season when water temperatures are still fairly warm and nights are cool
51
An aneroid barometer reads
atmosphere pressure differences and changes
52
A barometer that reads rain, change, or clear
tells you nothing
53
Aneroid barometer shows changes in atmospheric pressure using
a set hand. Tap the face to bring the pointer to the true position. The speed at which the need moves indicates the wind speed. Little or no change indicates that current conditions will continue
54
Clouds are
masses of small water droplets of tiny ice crystals that float in the air, there are three main types
55
Cirrus
the highest and are composed entirely of ice crystals. Usually they signal a change in the weather
56
Cumulus clouds
are heaped and billowy with a "cotton ball" appearance, They will often have flat gray bases, with puffy white topes. Then usually signal good weather, but can produce showers and thunderstorms
57
Nimbus clouds are
dark rain clouds. Cumulonimbus clouds are large heaps of rain clouds that are often anvil shapes. The are associated with thunderstorms and can produce gusty winds, thunder, rain, hail and lightening.
58
Stratus clouds are
layered, lowly, dull-colored clouds. The form in layers and usually bring drizzling rain or light-falling snow
59
Dew point
the temperature at which the air can no longer hold moisture and begins to unload slowly as fond.
60
Winds are names
from where they blow
61
Veering winds change
in a clockwise direction, such as a wind changing from north to east
62
Backing winds change
in a counterclockwise direction. A find changing from the south to from the east would be backing
63
Apparent wind is
shown on the wind vane of a moving vessel
64
Apparent wind speed is measure by
an anemometer
65
Coriolis Effect
Winds are deflected by the Earth's rotation
66
The wind pattern that generally influences movement of frontal systems over North America is
the Prevailing westerlies
67
Fog is
a cloud on the Earth's surface. It is visible condensations in the atmosphere. Its water or ice particles are smaller than rain or mist and those particles stay suspended in air
68
Form forms when
air cools to the point (dew point) when water vapor in the air begins to cool into tiny water droplets
69
fog is more likely to form
at night, and likelier as is gets later and later because the air cooling off more and more
70
Advection
the horizontal movement of air
71
Advection fog is created by
warm moist air flowing over cold coastal water. It is very common during winter warming and early spring thaws.
72
If air is at near moisture saturation, ...
moisture will condense out of the cooled air and form fog
73
Advection fog is worse
When winds are too light to mix the warm humid air near the ground with the cooler drier air above.
74
Sea smoke
looks like and is sometimes called steam. Cold, dry air blows over warmer water and the water evaporates into the lower layers of the air that is warmed by the water. The warmed air rises and is cooled by the cooler air above enough to for tiny droplets. This is most common in the fall because the cold winds bring cold air over the more slowly cooling warm water.
75
In the Northern Hemisphere, a wind that shift counterclockwise is a
Veering wind
76
direction of the surface wind is/are
deflected by the Earth's rotation
77
In the Northern Hemisphere, a wind that shifts counterclockwise is a _____.
Backing Wind
78
A weather forecast states that the wind will commence backing. In the Northern Hemisphere, this would indicate that it will _____.
Shift in a counterclockwise manner
79
A weather forecast states that the wind will commence veering. In the Northern Hemisphere this indicates that the wind will _____.
Shift in a clockwise manner
80
A local wind which occurs during the daytime and is caused by the different rates of warming of land and water is a _____.
Sea Breeze
81
Wind resulting from a land mass cooling more quickly at night than adjacent water is a _____.
Land Breeze
82
On a weather chart, a warm front is indicated by what symbol?
Line with red half circles on one side
83
The barometer is an instrument for measuring the _____.
Atmospheric Pressure
84
Which symbol on a weather chart represents a cold front?
Line with blue triangles
85
What is the weather chart symbol for an occluded front?
Line with purple half-circles and triangles
86
A local wind which occurs during the daytime and is caused by the different rates of warming of land and water is a _____.
sea breeze
87
Prior to reading an aneroid barometer, you should tap the face lightly with your finger to _____.
bring the pointer to its true position
88
Which symbol on a weather chart represents a Warm front?
Line with red half circles
89
Which weather chart symbol represents a stationary front?
Line with red circles on one side & blue triangles on the other
90
A boundary between two air masses is called a _____.
front
