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8th Grade Science > Weather > Flashcards

Flashcards in Weather Deck (183):
1

the 5 big guiding principles of Meteorology:

1. Hot air rises
2. Rising air expands & cools
3. As air rises, air pressure at the surface is lowered
4. Air travels from high pressure to low pressure
5. Cool air holds less moisture than warm air

2

Hot air is less ___ than cold air

dense

3

Add heat to gas and what 2 things happen?

1. molecules move faster
2. molecules spread out

4

Wind forms as ___ pressure air moves to areas of ___ pressure

high; low

5

the layers of the Atmosphere: from the top, down

Thermosphere
(550km from Earth)
Mesosphere
(80km from Earth)
Stratosphere
(50km from Earth)
Troposphere
(12km from Earth)

6

the layer of the Earth's atmosphere that you live in

Troposphere

7

the coldest layer of the Earth's atmosphere; lies directly below the uppermost layer

Mesosphere

8

the uppermost layer of the atmosphere

Thermosphere

9

the layer that contains most of the atmosphere's ozone; above the layer that you live in

Stratosphere

10

Why does air pressure decrease as altitude increases?

Air pressure decreases as you go up because the majority of air is closest to the Earth's surface due to gravity.

11

Explain why the temperature decreases & increases as you travel throughout the layers of the atmosphere.

The temp. decreases as you travel up in the troposphere b/c there is less air molecules the higher you go up.

The temp. increases in the stratosphere due to the ozone layer absorbing UV rays.

It decreases again in the mesosphere due to the few slow moving molecules.

It increases in the thermosphere due to the rapidly moving ions. Even though there are few air molecules, they are moving so rapidly that the temp. increases; however, it would still FEEL cold.

12

What gases is the atmosphere mainly composed of & what are their percents?

78% Nitrogen
21% Oxygen
1% Miscellaneous

13

Radiation:

the transfer of energy as ELECTROMAGNETIC WAVES

14

Radiation moves energy through space in...

waves, heating the Earth's surface

15

Through this method of heat transfer...

the earth recieves energy from the sun

15

The radiation absorbed by the land, water, and atmosphere is changed into...

thermal energy

16

50% of Radiation is...

absorbed by the Earth's surface

17

25% of Radiation is...

scattered & reflected by clouds & air

18

20% of Radiation is...

absorbed by ozone, clouds, & atmosphere

19

5% of Radiation is...

reflected by the Earth's surface (snow & pool/ocean water)

20

Conduction:

the transfer of thermal energy from one material to another by DIRECT CONTACT

21

Air is heated by conduction near...

the earth's surface

22

Thermal energy ALWAYS moves from ___ to ___ areas

warm to cold areas

23

When air molecules come into contact with a warm surface...

thermal energy is transferred into the atmosphere

24

Where is air heated by conduction?

near the earth's surface

25

Convection:

the transfer of thermal energy by the circulation or movement of a fluid (liquid or gas)

26

Convection currents are caused by...

the unequal heating of the atmosphere

27

Most thermal energy in the atmosphere moves by...

convection

28

What are the 4 steps in convection?

1. Heated air becomes less dense & rises
2. Air cools, becomes more dense & sinks
3. As the cool air sinks, it pushes the warm air up
4. The cool air is eventually heated again by the ground & again begins to rise

29

This continual process for convection creates a circular movement called a...

convection current

30

How are convection currents created?

by the uneven heating of the atmosphere

31

Air Pressure Demonstration: What were the 2 methods of heat transfer used to heat the water in the soda can?

•Conduction (can was touching hot plate)
•Convection (convection currents when boiling the water)

32

Air Pressure Demonstration: As the water started to boil, which phase change was occuring?

Evaporation

33

Air Pressure Demonstration: Where was the GREATEST amount of air pressure?

Outside the can because it was a lower temperature than inside the can.

34

Air Pressure Demonstration: Where was the LEAST amount of air pressure?

Inside the can because it had a higher temperature than outside the can.

35

Air Pressure Demonstration: Explain why the can collapsed.

Air travels from high pressure to low pressure, so when the can became surrounded by the low pressure air that was above the cooler temp. water, more air went into the can, causing it to collapse.

36

What is wind?

moving air from high to low pressure

37

Winds are named by...

where they come from

38

How is wind created?

by differences in air pressure

39

Wind is generally caused by the uneven ___ of the Earth

uneven heating

40

___ sun rays = hotter temperatures

direct

41

___ sun rays = cooler temperatures

indirect

42

Air that is warm & less dense ___ and creates an area of ___ pressure.

Air that is warm & less dense rises and creates an area of low pressure.

43

Air that is cold & more dense ___ and creates an area of ___ pressure.

Air that is cold & more dense sinks and creates an area of high pressure.

44

There is a change in global air patterns approximately every ___.

30° latitude

45

What are convection cells?

the circular patterns of air movement caused by the rising & sinking of air

46

Global Winds:

• are part of a pattern of air circulation that moves across the Earth
• blow over longer distances in a specific direction

47

Local Winds:

• blow over short distances & can blow from any direction
• types: sea breeze, land breeze,
valley breeze, mountain breeze, etc.

48

Where are the Doldrums?

near the equator

49

Why is the air calm in the doldrums?

there is very little change in temperature

50

Doldrums - area of low pressure at the ___

Equator

51

Doldrums - very little wind there because of ___ rising air

warm

52

Doldrums - "doldrums" mean foolish because...

it would be foolish to sail in that region

53

Where are the trade winds?

above and below the equator

54

Above the equator the trade winds are steady ___ winds. Below the equator, the trade winds are steady ___ winds. (direction)

northeast; southeast

55

Trade Winds - between ___ & the equator

30° latitude

56

Trade Winds - early ___ used them to sail from Europe to the Americas

traders

57

Trade Winds - go from ___ to ___

east to west

58

The ___ ___ are another area of calm. The air is cooling & ___ here.

horse latitudes; sinking

59

Horse Latitudes - areas of ___ pressure caused by sinking air at ___ N & ___ S

high; 30°; 30°

60

Horse Latitudes - the winds are very ___

weak

61

Horse Latitudes - How was this area named?

Legend: ships carrying horses from Europe to America got stuck due to lack of wind & would throw horses overboard to save drinking water & make the ship lighter

62

Where are the Westerlies the prevailing wind?

over much of the middle and higher latitudes

63

Westerlies - wind belts found between ___ and ___ N & S latitude

30° & 60° N & S latitude

64

Westerlies - flow in the ___ direction of the trade winds (___ to ___)

opposite; west to east

65

Westerlies - bring most of ___ weather

our

66

What is the Polar Front?

where the warm air of the westerlies meets the cold air of the polar easterlies

67

This causes ___ weather in the region where the ___ prevail.

unstable weather; westerlies

68

Polar Easterlies - wind belts found in both hemispheres between the ___ and ___.

poles & 60° latitude

69

Polar Easterlies - named for the ___ and ___ they come from.

direction & area

70

Jet Streams - narrow belts of high ___ winds in the upper troposphere & lower stratosphere

speed

71

Jet Streams - ___ north and south

shift

72

Jet Streams - control the ___ & ___ of storms (inportant to meteorologists who track storms)

direction & movement

73

Jet Streams - pilots fly with the jet stream when possible to ___ time & fuel

save

74

Coriolis Effect - ___ winds are affected by the coriolis effect

global

75

Coriolis Effect - the apparent ___ of winds because of the Earth's ___.

curving; rotation

76

Coriolis Effect - winds in the Northern hemisphere appear to curve to the ___

right

77

Coriolis Effect - winds in the Southern hemisphere appear to curve to the ___

left

78

A convection current is an alternating cycle in which ___ air is constantly being replaced by ___ air

warmer; cooler

79

Heat is released (energy is lost) in which phase changes?

condensation, freezing, deposition

80

Heat is absorbed (energy is added) in which phase changes?

evaporation, melting, sublimation

81

What is precipitation? What is the phase change?

rain, snow, sleet, or hail that falls from the clouds onto the Earth's surface; liquid to solid

82

What is infiltration?

the movement of water into the ground due to the pull of gravity

83

What is runoff?

water that flows across land & collects in rivers, streams, & eventually the ocean

84

What is groundwater?

the water located within the rocks below the Earth's surface

85

What are glaciers? What is the phace change?

an enormous mass of moving ice; solid to liquid

86

What is an example of perspiration? What is the phase change?

sweating; liquid to gas

87

What is transpiration? What is the phase change?

the process by which plants release water vapor into the air through their leaves; liquid to gas

88

What is wind?

moving air (moves high & low pressure)

89

What is Humidity?

the amount of water vapor or moisture in the air

90

As water evaporates, does the humidity of the air increase or decrease?

As water evaporates, the humidity of the air increases.

91

What is Relative Humidity?

the amount of moisture the air contains compared with the maximum amount it can hold at that particular temperature

92

How can the relative humidity become higher? (2 ways)

1. more water vapor in the air at a particular temperature
2. lower temperature with a particular amount of water vapor in the air

93

What is Condensation?

the change of state from a gas to a liquid

94

What % relative humidity will there be condensation?

Condensation is when a gas changes to a liquid when the air is saturated with 100% relative humidity.

95

What is Dew Point?

the temperature at which air must cool to be completely saturated

96

How is there condensation on a glass with ice in it?

the ice in a glass of water causes the air surrounding the glass to cool to its dew point, making the relative humidity 100% & causing condenstion to form

97

What is Saturated?

when air holds all the water it can at a given temperature

98

What is the relative humidity of saturated air?

Saturated air has a relative humidity of 100%

99

How is relative humidity found using a Psychrometer?

by taking the difference between the Dry-Bulb temperature and the Wet-Bulb temperature. then a chart is used to find the relative humidity.

100

What happens to relative humidity as air temperature increases?

relative humidity decreases as air temperature increases

101

What is a River?

a large natural stream of water flowing in a definite course that empties into an ocean, lake, or another body of water

102

What are Tributaries?

smaller streams or rivers that flow into bigger ones

103

What is a Watershed?

the land drained by a river system - the main river & tributaries are within it

104

What are Wetlands?

the area around the mouth of a river tht has fertile soil and marsh, freshwater, and saltwater habitats

105

What is a Delta?

a fan shaped deposit of sediment where a river slows down as it reaches a large body of water

106

What is an Ocean?

a large body of salt watet

107

What is Sediment?

sand/minerals

108

Why are river systems & the water cycle classified as CLOSED LOOP SYSTEMS? Tell the difference between open & closed systems.

River systems & the water cycle are both classified as closed loop systems because neither of them are dependent on things outside of their system. In the river system & water cycle, water flows continuously & the systems are never-ending. They don't need, for example, a human to continue the cycle by moving water from 1 place to another. An open loop system is dependent on outside factors to continue it's cycle.

109

What are the basic ingredients for weather?

temperature, pressure, volume, density

110

What do all weather events have in common?

clouds

111

Altitude: Stratus Cloud

below 6,500 ft (low)

112

Composition: Stratus Cloud

water droplets

113

What they look like: Stratus Cloud

grey clouds that cover the entire sky; layered

114

Weather/Precipitation: Stratus Cloud

drizzle (very light rain)

115

Altitude: Nimbostratus Cloud

below 6,500 ft (low)

116

Composition: Nimbostratus Cloud

water droplets

117

What they look like: Nimbostratus Cloud

dark grey; wet-looking; layered

118

Weather/Precipitation: Nimbostratus Cloud

continuously falling rain or snow (light to moderate)

119

Altitude: Stratocumulus Cloud

below 6,500 ft (low)

120

Composition: Stratocumulus Cloud

water droplets

121

What they look like: Stratocumulus Cloud

low lumpy clouds; usually some blue sky in between

122

Weather/Precipitation: Stratocumulus Cloud

can become nimbostratus

123

Altitude: Altocumulus Cloud

6,500 - 18,000 ft (middle)

124

Composition: Altocumulus Cloud

water droplets

125

What they look like: Altocumulus Cloud

grey puffy masses; sometimes in waves or bands

126

Weather/Precipitation: Altocumulus Cloud

indicates possible thunderstorms by late afternoon

127

Altitude: Altostratus Cloud

6,500 - 18,000 ft (middle)

128

Composition: Altostratus Cloud

water droplets & ice crystals

129

What they look like: Altostratus Cloud

layered across the sky; bumpy

130

Weather/Precipitation: Altostratus Cloud

often form ahead of storms with continuous precipitation

131

Altitude: Cirrus Cloud

above 18,000 ft (high)

132

Composition: Cirrus Cloud

ice crystals

133

What they look like: Cirrus Cloud

thin; wispy

134

Weather/Precipitation: Cirrus Cloud

fair, pleasant weather

135

Altitude: Cirrostratus Cloud

above 18,000 ft (high)

136

Composition: Cirrostratus Cloud

ice crystals

137

What they look like: Cirrostratus Cloud

thin; sheet-like; can see the sun/moon through clouds (halo around moon)

138

Weather/Precipitation: Cirrostratus Cloud

predicts rain or snow within 12-24 hours

139

Altitude: Cirrocumulus Cloud

above 18,000 ft (high)

140

Composition: Cirrocumulus Cloud

ice crystals

141

What they look like: Cirrocumulus Cloud

small, rounded white puffs

142

Weather/Precipitation: Cirrocumulus Cloud

fair, but cold weather

143

Altitude: Cumulus Cloud

below 6,500 ft (vertically developed)

144

Composition: Cumulus Cloud

water droplets

145

What they look like: Cumulus Cloud

puffy clouds; look like cottonballs

146

Weather/Precipitation: Cumulus Cloud

fair weather

147

Altitude: Cumulonimbus Cloud

6,000 - 50,000 ft (vertically developed)

148

Composition: Cumulonimbus Cloud

water droplets & ice

149

What they look like: Cumulonimbus Cloud

towering, dark clouds

150

Weather/Precipitation: Cumulonimbus Cloud

heavy rain; thunderstorms; hail; tornadoes

151

If you were outside for a day & were looking at the clouds fro time to time, what would you see that would indicate precipitation was on the way?

the clouds would become darker & their altitudes would become lower

152

What is an air mass?

a large body of air that has similar temperature & moisture throughout the whole air mass

153

What is a front?

sharp transition zone

154

Where do air masses form?

the land or the sea

155

What is a Maritime air mass?

an air mass that forms over water; it is wet/moist

156

What is a Continental air mass?

an air mass that forms over land; it is dry

157

What is a Polar air mass?

an air mass that forms over polar regions; it is cold

158

What is a Tropical air mass?

an air mass that develops over the Tropics; it is warm/hot

159

Describe the maritime Tropical (mT) air mass.

warm & moist

160

Describe the continental Tropical (cT) air mass.

hot & dry

161

Describe the maritime Polar (mP) air mass.

cold & showery (wet; precipitation)

162

Describe the continental Polar (cP) air mass.

cold & dry

163

What is a front?

a front is a boundary between 2 different air masses

164

All of the ___ & ___ is the same behind the front

moisture & air temperature

165

How does a cold front form?

the cold air mass moves under a warm air mass & moves the less dense warm air out

166

Weather: As the cold front passes there is a sudden drop in...

temperature

167

Weather: As the cold front passes there is heavy...

precipitation

168

Weather: As the cold front passes there is a sharp drop in...

humidity

169

Weather: As the cold front passes there are shifting/increased...

winds

170

After the cold front passes, what is the weather like?

1. colder temperatures
2. decrease in precipitation
3. lowered humidity

171

How does a warm front form?

a warm air mass meets & overrides a cold air mass

172

Weather: As the warm front passes temperature...

steadily increases

173

Weather: As the warm front passes there is light...

precipitation over a large area

174

Weather: As the warm front passes there is minimal change in...

humidity

175

After the warm front passes, what is the weather like?

1. temperature becomes warmer
2. no precipitation
3. usually nice weather

176

How does a stationary front form?

a cold front meets a warm front and stalls - no movement

177

Weather: As the stationary front passes there is similar weather as a...

warm front

178

Weather: As the stationary front passes there is little...

precipitation

179

Weather: As the stationary front passes the weather may last...

over several days

180

How does an occluded front form?

the cold air mass from the cold front meets the cool air that was ahead of the warm front. the warm air rises as these air masses come together

181

Type of Weather for an Occluded Front: mature...

storm development

182

Type of Weather for an Occluded Front: weather similar to a...

cold front