3.B.2 - Weather and Climate Flashcards
(226 cards)
1
Q
What is the atmosphere?
A
The layer of gases surrounding the Earth.
2
Q
What keeps the atmosphere in place?
A
Gravity.
3
Q
Describe the physical appearance of gases in the atmosphere.
A
Odourless and transparent.
4
Q
By international convention, what is the furthest extent of the atmosphere?
A
1000km above sea level.
5
Q
What is weather?
A
The condition of the atmosphere at a local level.
6
Q
What is climate?
A
The average weather conditions of a location based on the weather experienced over the past 30 years.
7
Q
Within what depth of the atmosphere is most of our weather and climate concentrated?
A
16km above sea level at the Equator and 8km above sea level at the poles.
8
Q
What is paleoclimatology?
A
The study of changes in climate throughout history.
9
Q
According to scientists, how old is the Earth?
A
4.5 billion years old
10
Q
True or False?: When the Earth first formed 4.5 billion years ago, there was an atmosphere.
A
False - There was no atmosphere.
11
Q
What was the surface of the Earth like when it first formed 4.5 billion years ago?
A
Molten
12
Q
What kick-started the formation of the atmosphere?
A
Volcanoes releasing gases from the Earth’s interior.
13
Q
What happened when the planet cooled during the formation of the atmosphere?
A
Water vapour that had been emitted by volcanoes condensed to form the oceans.
14
Q
What happened to the carbon dioxide in the atmosphere once water vapour condensed to create the oceans during its formation?
A
It dissolved into the oceans and began to make sedimentary rocks.
15
Q
When did life appear on Earth?
A
2 billion years ago.
16
Q
How did the appearance of life in the oceans affect the formation of the atmosphere?
A
Organisms began to photosynthesis, releasing oxygen into the atmosphere.
17
Q
What happened once there was sufficient oxygen in the atmosphere that had been photosynthesised by early life?
A
It formed the ozone layer, blocking out harmful UV radiation.
18
Q
How did the ozone layer affect the formation of the atmosphere?
A
Life was able to move to shallower depths of the ocean without being harmed by UV radiation, and photosynthesise more.
19
Q
True or False: The gases of the atmosphere are chemically combined.
A
False - the atmosphere is a mixture. None of the chemicals that compose it are chemically combined.
20
Q
What are the 5 categories of atmospheric components?
A
- Major components
- Variable components
- Inert gases
- Pollutants
- Non-gaseous substances
21
Q
What are the 2 variable components of the atmosphere?
A
- Nitrogen
2. Oxygen
22
Q
What percentage of the atmosphere is nitrogen?
A
78.1%
23
Q
What percentage of the atmosphere is oxygen?
A
20.9%
24
Q
True or False? : The major components of the atmosphere are passive gases which have little effect on our weather and climate.
A
True - Our weather and climate is mainly effected by smaller, more variable components.
25
What are the 3 variable components of the atmosphere?
1. Carbon dioxide
2. Water vapour
3. Ozone
26
What percentage of the atmosphere is carbon dioxide?
0.04%
27
What percentage of the atmosphere is water vapour?
5%
28
What percentage of the atmosphere is ozone?
Trace
29
What is responsible for the 0.01% rise in atmospheric carbon dioxide concentrations in recent years?
Human activities such as the combustion of fossil fuels and deforestation.
30
By scientific consensus, what is the affect of increasing carbon dioxide concentrations in the atmosphere?
Anthropogenic climate change
31
How does carbon dioxide cause climate change?
Ut contributes to the greenhouse effect by absorbing terrestrial long-wave radiation emitted by the Earth.
32
Why is the percentage of water vapour in the atmosphere variable?
Because it varies from place to place depending on temperature.
33
Which gas provides the majority of the Earth's greenhouse effect?
Water vapour
34
What does ozone do in the atmosphere?
Absorbs/filters incoming ultraviolet radiation.
35
What is the name of the chemical which depletes ozone in the atmosphere?
CFCs - chlorofluorocarbons.
36
What are the 4 inert gases in the atmosphere (in order of abundance)?
1. Argon
2. Neon
3. Helium
4. Krypton
37
What is the 3rd largest component of the atmosphere?
Argon
38
What percentage of the atmosphere is argon?
0.9%
39
What percentage of the atmosphere is neon, helium and krypton?
Trace
40
What are the 3 pollutants which make up the atmosphere?
1. Sulphur dioxide
2. Nitrogen oxides
3. Methane
41
What are the 3 types of nitrogen oxides in the atmosphere?
1. Nitrogen monoxide
2. Nitrogen dioxide
3. Nitrous oxide
42
What role do pollutants play in the atmosphere?
They assist with the greenhouse effect by absorbing outgoing terrestrial long-wave radiation.
43
What is the name given to the non-gaseous component of the atmosphere?
Particulates
44
Give 4 examples of particulates.
1. Dust
2. Volcanic ash
3. Rain
4. Snow
45
What percentage of the atmosphere is particulates?
Trace
46
True or False? : Particulate concentration does not vary spatially.
False - Particulate concentration does vary spatially.
47
What happens to atmospheric pressure as you increase altitude?
It decreases.
48
True or False? : Changes in atmospheric pressure with altitude depend on the layer of the atmosphere you are in.
False - Atmospheric pressure always decreases with altitude, regardless of your layer.
49
How can the atmosphere be divided up into 4 different layers?
By changes in temperature with altitude.
50
What is the term given to the act of dividing up the atmosphere into layers depending on changes in temperature with altitude?
Atmospheric stratification.
51
What are the 4 stratified layers of the atmosphere, from lowest to highest?
1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
52
What are the 4 isothermal boundaries between the layers of the atmosphere (from lowest to highest)?
1. Tropopause
2. Stratopause
3. Mesopause
4. Thermopause
53
What happens in the isothermal boundary layers between the layers of the atmosphere?
Temperature remains constant with changes in altitude.
54
What is the troposphere?
The layer of the atmosphere closest to the Earth.
55
What is the planetary boundary layer?
The lowest part of the atmosphere where friction between the air and the Earth exists.
56
In which layer of the atmosphere does nearly all weather and climate occur?
The troposphere.
57
True or False? : 50% of the mass of the atmosphere is found in the troposphere.
False - 75% of the mass of the atmosphere is found in the troposphere.
58
What percentage of water vapour and clouds can be found in the troposhere?
99%
59
What is the height of the tropopause at the Equator?
20km above sea level
60
What happens to temperature as you increase your altitude in the troposphere?
It decreases with altitude.
61
What lapse rate does temperature decrease by with altitude in the troposphere?
The ELR - environmental lapse rate, which is a decrease of 6.49 degrees C for every 1km rise in altitude.
62
Why does temperature decrease with altitude in the troposphere?
Because the air is warmed by the adjacent ground as it emits outgoing terrestrial long-wave radiation.
63
What happens to temperature as you increase your altitude at the poles?
There is a temperature inversion and temperature actually increases with altitude at the poles!
64
Why is the troposphere sometimes called the convective region of the atmosphere?
As it contains all of the convective activity of the atmosphere.
65
What is the name of the boundary between the troposphere and the stratosphere?
The tropopause.
66
What is an isothermal layer?
A layer of the atmosphere where there is no change in temperature with changes in altitude.
67
True or False? : The height of the tropopause is constant with spatial and temporal variation.
False - There are latitudinal and seasonal variations in its height.
68
What is the role of the tropopause?
It acts as a lid for convection in the atmosphere, and as an upper ceiling for weather.
69
What is the stratosphere?
The 2nd layer of the atmosphere.
70
What is the height of the stratopause at the Equator.
50km above sea level.
71
What percentage of atmospheric mass is found in the stratosphere?
20%
72
What happens to temperature as you increase your altitude in the stratosphere?
It also increases.
73
Why is there an increase in temperature with altitude in the stratosphere?
The ozone layer is located here, where the UV rays of the Sun are absorbed by ozone.
74
Why is the stratosphere stable?
Layers of warmer air sit above layers of cooler air.
75
True or False? : The stratosphere is very dry.
True - There is no clouds or weather.
76
In which layer of the atmosphere do planes fly, and why?
The stratosphere - because it is dry so there are no clouds.
77
How does the stratosphere protect the Earth from meteorites?
It is the layer in which they burn themselves out.
78
What is the name of the isothermal layer between the stratosphere and the mesosphere?
The stratopause.
79
What is the former name of the stratopause?
The mesopeak.
80
What is the mesosphere?
The 3rd layer of the atmosphere.
81
What happens to temperature as you increase altitude in the mesosphere?
Temperature decreases.
82
Why does temperature decrease with altitude in the mesosphere?
Because there is no ozone to absorb incoming radiation.
83
Which 3 layers compose the middle atmosphere?
The stratosphere, the mesosphere and the thermosphere.
84
What is the name of the isothermal layer between the mesosphere and the thermosphere?
The mesopause.
85
What is the height of the mesopause at the Equator?
100km above sea level.
86
What is temperature like at the mesopause?
The coldest naturally occurring place on Earth.
87
What is the thermosphere?
The top layer of the atmosphere.
88
What happens to temperature with altitude in the thermosphere as you increase your altitude?
It increases with altitude.
89
Why does temperature increase with altitude in the thermosphere?
Unfiltered radiation from the Sun causes molecules of oxygen to break apart into ions, releasing energy.
90
Why would a person not feel warm in the thermosphere?
The layer is so close to the vacuum of space that few gas atoms would come into contact with them.
91
What orbits around the Earth in the thermosphere?
The International Space Station.
92
What is the primary source of energy for the Earth?
The Sun.
93
What is insolation?
Energy emitted by the Sun. It is ultraviolet, short-wave and high frequency.
94
What is the overall factor which causes weather on planet Earth?
Insolation.
95
What 4 astronomical factors affect the amount of insolation the Earth receives?
1. The solar constant
2. The distance from the Sun.
3. The altitude of the Sun in the sky.
4. The length of night and day.
96
What is the solar constant?
The rate at which energy reaches the surface of the Earth.
97
What 3 processes can happen to radiation once it enters the atmosphere?
1. Absorption
2. Reflection
3. Scattering
98
What absorbs insolation in the atmosphere?
Ozone, oxygen, water vapour, carbon dioxide, particultaes and clouds (to a lesser extent).
99
What reflects insolation in the atmosphere?
Clouds - their white nature gives them a high albedo.
100
What scatters radiation in the atmosphere?
Particulates of dust or molecules of gas.
101
What is scattering?
The diversion of radiation in all directions.
102
What is diffuse sky radiation?
Radiation which reaches the surface of the Earth after being scattered.
103
What is the solar radiation atmospheric cascade?
The process in which incoming insolation is either absorbed, reflected or scattered by the components of the atmosphere before it can reach the surface of the Earth.
104
What percentage of insolation in the solar radiation atmospheric cascade directly reaches the Earth?
24%
105
What percentage of insolation in the solar radiation atmospheric cascade is absorbed?
28% (25% by the atmosphere's gases, 3% by clouds).
106
What percentage of insolation in the solar radiation atmospheric cascade is reflected?
27% (23% by clouds, 4% by the surface of the Earth).
107
What percentage of insolation in the solar radiation atmospheric cascade is scattered?
21% - this reaches the Earth as diffuse sky radiation or is scattered back into space.
108
What happens to insolation once it reaches the surface of the Earth?
It is converted into heat energy, then emitted back into the atmosphere as outgoing, long-wave, low-frequency, infrared terrestrial radiation.
109
What type of radiation is terrestrial radiation?
Infrared (long-wavelength, low frequency)
110
What percentage of terrestrial radiation is absorbed by greenhouse gases?
94%
111
What percentage of terrestrial radiation makes it out into space?
6%
112
What would the temperature of the Earth be without the greenhouse effect?
-18 degrees
113
True or False? : The planet has a fairly constant temperature.
True - on the whole there is no loss or gain of heat. Insolation is equal to outgoing terrestrial radiation.
114
Describe the budget of radiation at the different latitudes of the Earth.
At the tropics there is a net gain in radiation (insolation > terrestrial radiation), but at the poles there is a net loss (insolation < terrestrial radiation).
115
True or False? : The poles receive more insolation than the tropics.
False - The tropics receive more insolation than the poles.
116
What 4 factors cause there to be an imbalance in the insolation received at different latitudes?
1. Distance to the Sun.
2. Depth of the atmosphere
3. Angle of rays
4. Albedo effect
117
How does distance from the Sun affect the amount of insolation a place receives?
Tropical latitudes are closer to the Sun than polar latitudes due to the curvature of the Earth, thus insolation must travel over further distances in order to reach the poles. This means greater exposure to the solar radiation atmospheric cascade.
118
How does the depth of the atmosphere affect the amount of insolation a place receives?
The atmosphere is thickest at the Equator and thinnest at the poles. Due to the tilt of the Earth, insolation does not enter at a perpendicular angle, thus insolation reaching the poles must travel through a greater depth of atmosphere.
119
How does the angle of rays affect the amount of insolation a place receives?
Due to the curvature of the Earth, insolation strikes the poles at an angle. This means that energy received is dispersed over a wider are than at the tropics, reducing its intensity.
120
How does the albedo effect affect the amount of insolation a place receives?
The higher the albedo, the higher the percentage of radiation reflected back into space. Light, polar ice has a high albedo, whereas the dark vegetation of the tropics has a low albedo.
121
Why are global mechanisms of heat re-distribution necessary?
To prevent the tropics from overheating and the poles from cooling.
122
What is latent heat?
The amount of energy required to change the state of a substance without affecting its temperature.
123
What is pressure?
The weight of the air pressing down on the surface of the Earth.
124
What is high pressure?
Descending air.
125
What is low pressure?
Rising air.
126
What is wind?
The movement of air along a pressure gradient, from an area of high pressure to an area of low pressure.
127
What is a pressure gradient?
The difference in pressure between 2 regions of varying pressure.
128
What is the Coriolis force?
A phenomenon observed in rotating objects, where fluids curve as they travel across the object's surface.
129
In which direction does the Earth rotate?
Eastwards (from west to east).
130
True or False? : Due to the varying width of the Earth, points at the Equator are travelling at a greater speed than points at the poles.
True.
131
What is atmospheric circulation?
The large-scale redistribution of air in the atmosphere to counter-act imbalances in the global heat budget.
132
What are the 2 processes which aim to redistribute heat from the Equator to the poles to counteract a global imbalance in the heat budget?
1. Atmospheric circulation (the tri-cellular model)
| 2. Oceanic circulation (ocean currents)
133
What are the 3 cells of the tri-cellular model?
1. The Hadleuy cell
2. The Ferrell cell
3. The Polar cell
134
True or False? : The tri-cellular model occurs in both hemispheres.
True - but most models show it in action in the Northern Hemisphere.
135
Explain the Hadley cell.
A low pressure region exists at the ITCZ where air is rising due to maximum insolation from the Sun. This makes the rising limb. It condenses to form clouds. It migrates north to try re-balance the heat budget, but the increase in latitude cools it and it descends at 30 degrees. This creates a high pressure region and the descending limb. At ground level, some air travels from this region of high pressure to the low-pressure region at the ITCZ as the north-east trade winds.
136
Explain the Ferrell cell.
The remaining air is diverted northwards. It travels as winds known as the south-westerlies. At 60 degrees it meets colder, denser, south-migrating air from the Polar cell, and is uplifted by frontal uplift. This creates an area of low pressure and the rising limb of the cell. Up in the atmosphere some air travels southwards back to the Equator, but the remaining air continues to travel north to the pole.
137
Explain the Polar cell.
The remaining air cools and descends to form a high pressure region. At the surface the air is drawn along a pressure gradient to the low pressure region of the Ferrell cell, forming winds called the easterlies.
138
True or False? : The Ferrell Cell is a result of the other 2 cells.
True - it is powered by the Hadley and Polar cells.
139
What are ocean currents?
The movement of surface water to redistribute a global imbalance in the heat budget.
140
What percentage of insolation is received by the oceans?
67% - as oceans cover 67% of the Earth.
141
What percentage of the global heat budget is affected by ocean currents?
25%
142
What 2 properties of the oceans mean that they absorb heat differently to land?
1. Specific heat capacity - water has a higher specific heat capacity than land.
2. Transparency - water can absorb heat down to greater depths.
143
What way do ocean currents circulate in the Northern Hemisphere?
Clockwise
144
What way do ocean currents circulate in the Southern Hemisphere?
Anti-clockwise
145
In thermohaline circulation, what happens to water as it migrates from the Equator to the poles?
It cools and evaporates, increasing the salinity of the water. Cooler, saltier water sinks to greater depths and moves slowly.
146
What is upwelling in thermohaline circulation?
The process in which deeper, denser, cooler water is brought back up to the surface where it warms.
147
What does thermohaline circulation ensure?
The world's oceans are continually mixed.
148
What is continentality?
Distance of land from the sea.
149
How does continetality affect climate in the summer?
The oceans act as a cooling influence on coastal areas.
150
How does continetality affect climate in the winter?
The oceans act as a warming influence on coastal areas.
151
How does altitude affect climate?
As we are situated in the troposphere, temperature decreases with altitude as the distance from the planetary boundary layer increases.
152
What is the most common system used for classifying climates?
The Köppen climate classification system
153
What are the 5 climatic groups of the Köppen climate classification system?
```
A - Tropical
B - Arid
C - Temperate
D - Continental
E - Polar
```
154
What is climate type A in the Köppen climate classification system?
Tropical climates
155
What is climate type B in the Köppen climate classification system?
Arid climates
156
What is climate type C in the Köppen climate classification system?
Temperate climates
157
What is climate type D in the Köppen climate classification system?
Continental climates
158
What is climate type E in the Köppen climate classification system?
Polar climates
159
Using the Köppen climate classification system, what do the 2 proceeding letters represent?
The 1st letter represents precipitation, the 2nd letter represents temperature.
160
Summarise the conditions of a tropical climate.
Wet and hot, with all months having an average temperature above 18 degrees and annual precipitation over 1500mm.
161
Where are tropical climates found?
In an unbroken belt along the Equator.
162
Why is precipitation abundant in tropical climates?
Their position means that they receive a lot of insolation, thus air is warmed and rises. This causes convectional rainfall.
163
True or False? : There are virtually no thermal seasons in a tropical climate.
True, seasons are distinguished by variations in rainfall instead of temperature.
164
True or False? : It is warm at night in a tropical climate.
True - the cloud cover produced during the day restricts heat loss.
165
Summarise the conditions of an arid climate?
Dry and hot, with a deficiency of precipitation throughout the year.
166
What are the 2 types of arid climate?
1. Desert climates
| 2. Semi-arid climates
167
What distinguishes a desert climate from a semi-arid climate?
Desert climates receive so little precipitation that vegetation cannot be sustained at all. Semi-arid climates receive enough precipitation to subsidise some forms of vegetation.
168
Summarise the climatic conditions of a temperate climate.
Distinct seasonal change: hot summers and mild winters.
169
Were are temperate climates found?
The mid-latitudes.
170
What are the 3 types of temperate climate?
1. Humid subtropical climates
2. Oceanic climates
3. Mediterranean climates
171
What makes a humid subtropical climate?
Hot and humid summers with semi-mild winters.
172
What makes an oceanic climate?
Cool summers and cool winters. They lack a dry season with precipitation throughout the year. The UK is an example.
173
What makes a Mediterranean climate?
Rainy winters, but hot, dry summers.
174
What differentiates a humid subtropical climate from a Mediterranean climate?
Mediterranean climates have dry summers; humid subtropical climates have wet summers.
175
Summarise the climatic characteristics of a continental climate.
Great continentality produces a range in temperatures. Warm summers and cool winters due to specific heat capacities and a lack of a moderating influence from the sea.
176
Summarise the climatic characteristics of a polar climate.
Snow and ice throughout the year. All-year round cold temperatures sitting below 10 degrees. Dry due to descending air.
177
What is the thermal equator?
The part of the Earth which receives the most intense heat from the Sun.
178
What is the difference between the thermal equator and the geographical Equator?
The thermal equator has no fixed position.
179
What is the result of the moving height of the Sun in the sky?
2 solstices a year. A solstice in 1 hemisphere is the opposite solstice in the other.
180
What is a solstice?
A day where we receive the most/least hours of daylight.
181
At the time of the summer solstice in the Northern Hemisphere, where is the thermal equator?
The Tropic of Cancer.
182
At the time of the winter solstice in the Northern Hemisphere, where is the thermal equator?
The Tropic of Capricorn.
183
What is an equinox?
The point equidistant between the Sun's most northerly and southerly extent.
184
What happens to the length of day during an equinox?
It is equal to the length of night.
185
When are the 2 equinoxes?
The March equinox and the September equinox.
186
When is the summer solstice in the Northern Hemisphere?
Around the 21st June
187
When is the winter solstice in Northern Hemisphere?
Around the 21st September.
188
What does ITCZ stand for?
Intertropical Convergence Zone
189
Where is the position of the ITCZ?
On the thermal equator.
190
What is the pressure like at the ITCZ?
Low - air is rising here due to the most intense solar heating, thus the trade winds converge here.
191
What weather is associated with the movement of the ITCZ?
Precipitation, as the ITCZ is usually situated over the oceans. It creates a rainy season in the area it moves over.
192
What is a monsoon?
A seasonal reversal in the direction of winds, followed by corresponding changes in precipitation.
193
What causes a monsoon?
Differences in pressure between the land and the sea, caused by different specific heat capacities.
194
What is the golden rule of a monsoon?
Monsoons always blow from a colder region to a warmer region.
195
What percentage of the world's population live in a region affected by monsoons?
Over 60%
196
Name a case study fora monsoon climate.
India
197
True or False? : There are 2 monsoons in India.
True - the summer monsoon and the winter monsoon.
198
What weather is associated with the summer monsoon in India?
Heavy rainfall.
199
Explain the summer monsoon in India.
The ITCZ migrates northwards. This brings heavy rainfall with it. Greater insolation over Asia heats the land quicker than the sea, creating a low pressure zone.A pressure gradient develops between the land and the sea, and this brings moist air in from the oceans. This is forced to rise through orographic uplift due to the Himalayas where water vapour condenses to form clouds and precipitation.
200
Where is the wettest place on Earth?
Mawsynram, India - 11,800 mm of rainfall a year!
201
What percentage of its rainfall does India receive during the summer monsoon?
90%
202
What percentage of India's GDP comes from agriculture?
18%
203
What percentage of the Indian population works in agriculture?
55%
204
Why is the summer monsoon important in India?
1. Agricuture
2. Livestock
3. Aquifer recharge
4. Hydroelectric power
205
What dangers does the summer monsoon pose in India?
1. Pluvial flooding in cities
| 2. Mudslides in rural areas
206
How many people were killed by the summer monsoon in Bangladesh in 1974?
28,700 people.
207
What happens during the winter monsoon in India?
The opposite of the summer monsoon - a dry season is created in India as the ITCZ migrates south and the land cools at a faster rate than the sea, forming a high pressure system over the land that draws winds to the low pressure system over the sea.
208
What type of climate does the UK have?
A temperate climate, specifically an oceanic once.
209
Summarise temperature in the UK.
Overall temperatures are cool with infrequent extremes. We have mild winters and warm summers.
210
Describe spatial variations in temperature in the UK.
The north of the country is warmer than the south, and the west of the country is warmer than the east.
211
What is the average annual temperature in London?
Higher than 11 degrees.
212
What is the average annual temperature in the Scottish Highlands?
Less than 4 degrees.
213
Why is temperature higher in the south of the UK than in the north?
Latitude - the angle of the Earth relative to the Sun means insolation has to travel through more of the atmosphere, and is less intense.
214
Why is the west of the UK warmer than the east?
The influence of the Atlantic Ocean and the Gulf Stream.
215
What is the Gulf Stream?
A fast-moving ocean current forming part of the thermohaline circulation system, that originates from the Gulf of Mexico before it crosses the Atlantic towards the UK.
216
What other factor affects spatial variation in temperature in the UK besides latitude and maritime influences?
Altitude.
217
Describe spatial variation in precipitation in the UK.
The west of the UK receives more rainfall than that of the east.
218
Annually, how much rainfall falls on the Lake District on average?
Over 3,000mm a year.
219
Annually, how much rainfall falls on Essex on average?
Less than 600mm a year.
220
What 2 types of rainfall affect the UK?
Orographic rainfall and frontal rainfall.
221
What causes seasons in the UK?
The inclination of the Earth's axis in relation to the Sun.
222
What is an air mass?
A body of air with uniform weather conditions.
223
How are air masses defined?
Based off their source regions.
224
What 2 properties does the name of an air mass describe?
1. Its temperature
| 2. Its humidity
225
What system is used to classify air masses?
The Bergeron classification system.
226
Under the Bergeron classification system, what does the first letter represent?
The surface of the source region, which will tell you its moisture properties.
