Topic 1: Hadardous Earth✅ Flashcards
1
Q
What is warm air?
A
Low pressure
2
Q
What is cold dry air?
A
High pressure
3
Q
What are 3 natural factors that have caused climate change?
A
Asteroids
Volcanos
Orbital
4
Q
What is the correct structure of the earth from outwards in?
A
Crust
Mantle
Outer core
Inner core
5
Q
Which layer of earth is found beneath the crust?
A
Mantle
6
Q
What is the asthenosphere?
A
The upper mantle
Below the crust and below the lithosphere.
(Middle mantle)
7
Q
What is the lithosphere?
A
The CRUST both oceanic and continental
8
Q
Which type of crust is heaviest?
A
Oceanic
9
Q
Which crust is thicker continental or oceanic?
A
Continental
10
Q
What is the lithosphere broken down into?
A
Tectonic plates
11
Q
What tracks how plates move and behave?
A
GPS
12
Q
What is magma called above the surface?
A
Lava
13
Q
What does viscous mean?
A
How thick and sticky something is
14
Q
What is a ridge push?
A
Gravity force that causes the plate into a subduction zone. It works with the slab pull. Weaker than the slab pull.
15
Q
Where do convection currents happen?
A
In the mantle
16
Q
What do convection currents cause?
A
Movement in the plates due to the rise and fall of rock in the asthenosphere
17
Q
What is slab pull
A
Is the strongest force causing subduction
18
Q
How are hurricanes categorised?
A
Wind speed
19
Q
What magnitude was hurricane Catarina?
A
5
20
Q
What is a plate margin?
A
Where two tectonic plates meet.
21
Q
What are the types of plate boundaries?
A
Divergent, convergent and conservative.
22
Q
What happens at a conservative plate margin?
A
Two plates slide past each other
Causes earthquakes and tsunamis
23
Q
What happens at a convergent plate margin?
Both Continental plates
A
Two continental plates move towards each other.
Mountains are formed
24
Q
What happens at a divergent plate margin?
A
Two plates move away from each other
Causes a new crust as magma rises and forms underwater mountains
25
What plate margin are rift valleys associated with?
Divergent
26
What is a good example of a rift valley?
The great rift valley in East Africa
27
Which type of plate margin has a subduction zone?
Convergent
| Oceanic and continental
28
What plate margin are shield volcanos associated with?
Divergent
29
What plate margin causes fold mountains?
Convergent
| Continental and continental
30
What is a subduction zone?
The area where the oceanic plate is pushed under a continental plate.
(Convergent)
31
Can volcanos and earthquakes occur at convergent plate margins?
Yes
| Composite volcanos
32
What volcano is found along convergent plate boundaries?
Composite
33
What causes plates in conservative boundaries to get stuck?
Friction
34
What is liquefaction?
soil mostly loses strength and stiffness in response to stress such as shaking during an earthquake. The material that is ordinarily a solid behaves like a liquid.
35
Is the San andreas fault along a conservative plate margin?
Yes
36
Why do volcanos occur in convergent plate margins?
In subduction magma rises through cracks in the bedrock called vents.
37
Why do volcanos occur at hotspots?
A plume of hot mama rises from the mantle to the surface, causing large flow of heat from the mantle to the crust. Magma becomes lava.
38
Characteristics of composite volcanos:
They erupt andesitic lava which has high silica content.
Lava can not flow very far
Very violent but NOT frequent
Eruptions are explosive
39
Shield volcanos
Not very explosive
They erupt basaltic lava low silica level: it is runny spreads over a large area
No larva bombs
40
What is large scale movement of air?
Wind
41
What are trade winds?
Surface winds that blow from 30 degrees north and south of the equator.
The winds blow back to the equator
42
In the southern he hemisphere, trade winds will blow from _______ to _________ until the reach the equator.
South east
| North west
43
In the northern he hemisphere, trade winds will blow from _______ to _________ until the reach the equator.
North east
| South west
44
What are westerlies?
Wind that blow from 30 degrees north and south to the POLES.
45
In the southern he hemisphere, westerlies will blow from _______ to _________ until the reach the south pole.
North west
| South east
46
In the northern hemisphere, westerlies will blow from _______ to _________ until the reach the north pole.
South west
| North east
47
What are two types of surface winds?
Trade winds (to the equator)
Westerlies (to the poles)
48
Properties of winds:
1. Caused by differences in air pressure.
2. Large scale air movements.
3. Move from high pressure areas to low pressure areas.
49
At what degree does air cool and sink north and south of the equator?
30 degrees(they move as surface winds)
50
What does raising hot air form?
Rising hot air forms a low-pressure belt
51
High pressure!
When air cools and falls, this results in a high pressure belt with no clouds and minimal rainfall.
52
What happens at 60 degrees north and south?
cold air blown from the poles meets warm air surface winds. Because the warmer air is less dense, it rises and forms a low-pressure belt.
The air splits, with some returning back towards the equator and the rest heading to the poles.
53
What happens to air at the poles?
The high pressure belt will move back to the equator as surface winds.
54
A low pressure belt?
- raising air
- clouds
- rain
Usually the equator and between 50° and 70° latitude.(north and south CHECK
55
Examples of low pressure in the northern hemisphere:
Aleutian low and the Icelandic low.
56
What are deep ocean currents caused by?
Deep ocean currents are caused by differences in water density.
(Thermohaline circulation)
Water freezing in polar regions causes the surrounding water to become saltier and therefore denser.
The sinking of this dense water lets warm water flow in near the surface. This warm water will then cool and sink.
57
How is warm water is transferred to Western Europe from the Caribbean?
The gulf stream
58
What is the name of the circulation system that causes deep ocean currents?
Thermohaline circulation
59
Surface currents transfer heat ______ the equator
Away from (shallower)
60
How is a low pressure belt formed from the Hadley cell?
Air rises where the Hadley cells from each hemisphere meet. This creates a belt of low pressure.
61
How is a high pressure belt formed from the Hadley and ferrel belt meeting?
Air sinks where the Ferrel and Hadley circulation cells meet. This creates a belt of high pressure.
62
What are the conditions in tropical climate zones?
High rainfall
| High temperatures
63
What type pf ocean current is the gulf stream?
Surface current
64
What are the conditions in tropical climate zones?
Winds move from high pressure areas to low pressure areas.
65
What are the three names of the global atmospheric circulation cells found in EACH hemisphere?
Polar cell
Hadley cell
Ferrel cell.
66
How long do interglacial periods usually last?
8-12 thousand years
67
What is the greenhouse effect?
The greenhouse effect happens when greenhouse gases (e.g. carbon dioxide, methane) absorb heat that has been reflected off the Earth and re-radiate this heat back towards Earth.
68
How long did the Quaternary period last?
2.588 million years
69
How long did the Neogene period last for?
21.4 million years
70
How long do glacial periods last for?
About 100 thousand years.
71
Sources for climate change evidence:
```
Ice cores
Tree rings
Pollen analysis
Temperature records
Sediment cores
```
72
What geological period are we currently in?
Quaternary period
73
When was the mini ice age?
1600-1685
74
When was the medieval warm period?
950-1100 AD
75
The UK's air masses:
The climate of the UK today is influenced by six air masses, leading to different weather conditions that contribute to four distinct climate regions.
The north-west - tends to experience mild winters and cool summers
The north-east - tends to experience cold winters and cool summers
The south-west - tends to experience mild winters and warm summers
The south-east - tends to experience cold winters and warm summers.
76
How often does the earth's tilt change?
41,000 years
77
What is the length of the cycle of earth wobbling on its axis?
22 thousand years
78
How often does the earth's orbit change from circular to elliptical?
Every 96,000 years
79
What emits methane?
- The digestive system of cows
| - rice paddies
80
What is an example of an industry process that releases methane?
Clement (made from limestone contains a lot of carbon co2 is released when it is made
Decay of industrial waste also produces methane
81
During____ plants take in co2 from the atmosphere and convert it into food.
Photosynthesis
82
Proof of human enhanced sea level rise:
- Global sea level rise increasing by 210 mm since 1900(melting ice)
- more extreme weather events (more frequent)
The ice sheets in the poles are getting thinner (13 % each decade)
- world increased by 1 degree since 1880
- all ten of the hottest years have been post 2001
83
The natural green house effect:
Greenhouse gases cause the greenhouse effect. This helps keep the Earth warm enough for life. But, the greenhouse effect can cause global warming if too strong. The process is:
The Sun emits short wavelength
infrared radiation that enters the atmosphere and travels towards the Earth’s surface.
The Earth absorbs some of this radiation, but long wavelength radiation is reflected back into the atmosphere.
Greenhouse gases can't absorb the frequency of radiation emitted by the Sun, but they can absorb the longer wavelength reflected radiation.
The gases re-radiate this energy.
Temperature at the Earth’s surface rises.
84
Will climate change change the distribution of species?
Yes
85
How much did hurricane Katrina cost the USA?
125 billion
86
By 2100 how much is the temperature expected to rose by?
2.8-3.2 degrees
87
Rising sea temperatures are causing the _______ of sensitive _______
Bleaching
| Corals
88
What graphs predict the best and worse case temperature scenarios as a result of climate change?
Temperature projection graphs
89
What are the conditions in the eye of a tropical cyclone?
```
No clouds
High temperature
Low pressure
No rain
Light winds
```
90
What are the 6 sources of climate change evidence?
- Pollen analysis
- Ice cores
- tree rings
- sediment cores
- temperature records
- historical records
91
How does pollen analysis show climate change?
- it can be preserved in sediment
| - comparing plant pollen from sediment plant pollen can show the differences from the past climate.
92
How do tree rings show climate change?
Every year, a new ring forms in the trunks of trees.
Rings are thicker in good conditions for growth (temperate and wet climate).
Counting the number of tree rings can show that tree's age.
Tree rings give us data on the climate and temperature for up to the last 10,000 years.
93
How do ice cores show climate change?
Every year a new layer of ice freezes on top of the previous ice sheet
Examining the gasses in each layer of ice can show us what the temperature was like thousands of years ago.
-sometimes there are fossils and sediment that can provide more information.
94
How do temperature records show climate change?
Temperatures have been recorded globally since 1850, however, global records are a lot better from the last 50 years.
This data is very reliable but only stretches back 170 years.
95
Give 2 possible effects of climate change:
Possible effect 1:
POINT!Global climate change will cause sea levels to rise.
EXPLAIN: rising sea levels will affect approximately 80 million people and will result in a massive migration away from the coast. This has the potential to lead to over population in some areas.
Possible effect 2:
POINT: Global climate change will cause an increased frequency of droughts.
ExPLINTION: this will stop crops from growing in affected areas, which could cause malnutrition and starvation.
96
Four possible effects of global climate change:
Increased frequency of flooding.
Increased frequency of extreme weather events.
Changes in farming patterns.
Changes in animal/plant/disease distribution.
97
Where are composite volcanos usually found?
At destructive plate boundaries(convergent)
98
What happens at the collision zone?
Fold mountains are formed
99
What is the characteristics of composite volcanos?
- occur at convergent plate boundaries
- the water reacts with magma tp form gasses. This causes subducted crust to erupt
- very explosive, ash explosions
- erupt andesitic lava(high silica) very thick and sticky
- can't flow far forms a steep-sided cone.
Eg. Mount Fuji in Japan
100
Characteristics of shield volcanos:
- occur at hotspots or divergent plate boundaries.
- not very explosive made up of only lava
- erupt basaltic lava(low silica) very runny
-flows quickly over a large
area forming a gentle-sided volcano(no massive mountains)
101
Characteristics of hotspot volcanos:
- plume of hot magma moves towards the surface.
- ballistic lava (low silica)
- they remain stationary but the crust moves above them, it creates volcanic islands.
Eg. Hawaii is a chain of hotspot volcanos in the pacific plates.
102
What are storm surges?
Storm surges are large sea level rises brought about by high winds and low pressure.
It leads the sea to flood costal areas
103
In cyclone Nargis, how manny people are dead and missing?
84,000 people dead
| 53,800 missing
104
Physical hazards of tropical cyclones:
Storm surges
Costal flooding
High winds
Landslides intense rainfall
105
Whar do meteorologists do?
Build models to forecast weather and cyclones
106
How can we reduce the impacts of tropical cyclones?
- weather forecasting
- storm surge defences
- evacuations
107
What are the 3 types of vulnerabilities with tropical cyclones?
Social
Economic (high dependence on agriculture)
Physical
108
2environmental impacts of hurricane Katrina:
Oil spills
| Damage of costal areas
109
Where did hurricane Katrina strike on 29th of August 2005?
Mississippi
| Louisiana
110
Primary effects of hurricane Katrina:
1,836 dead
154,522 houses were destroyed
The electricity for over 3 million people were cut off.
Many people in New Orleans
.
80% of New Orleans was flooded
Coastal habitats were damaged and bridges & infrastructure collapsed.
111
In hurricane Katrina, how many evacuated?
1.7 million people were evacuated from the states of Mississippi and Louisiana before the storm struck.
112
How many people were rescued by the coast guard in New Orleans
35000
113
What produces heat in the earth's core?
Radioactive decay
114
How high was the storm surge in cyclone Nargis?
7.6 m
115
When was the first batch of aid allowed in as a response to cyclone Nargis?
9 May
116
How high were the winds in cyclone Nargis?
120 MpH
117
Where are shield volcanos found?
Divergent or hotspots
118
What is pyroclastic flow?
Pyroclastic flows are currents of hot ash, lava and gas that can move downhill at speeds of up to 500 km/h during an eruption.
119
In the decade before cyclone Nargis large amounts of ______ forest had been cut down. It reduced the natural protection of the coast line.
Mangrove
120
Can earthquakes happen in all 3 plate margins?
Yes
121
Parts of an earthquake:
Seismic waves
Epicentre
Focus
122
Earthquakes at divergent margins:
pressure can build up from cracks in the plates when they move apart. This can cause earthquakes.
123
Earthquakes at conservative margins:
there can be friction between plates because they aren't smooth. A build up of friction will cause a snap(an earthquake)
124
Earthquakes at convergent margins!
a plate can get stuck as it moves under another. This can cause earthquakes.
125
What measures earthquakes?
The moment magnitude scale
126
What is the focus of an earthquake?
Pressure is released underground and where energy comes from.
-this is where the strongest waves do the most damage
127
Seismic waves
Energy from the focus in shock waves
-most damage will occur in places where earthquakes are strongest.
128
What is the epicentre of an earthquake?
The place on the surface that is directly above the centre of the earthquake.
129
What are shallow focus earthquakes?
Earthquakes where the focus is close to earths surface.
| 0-70km
130
What are deep focus earthquakes?
Earthquakes where the focus is more than 70km under earth's surface
- usually happen at convergent plate boundaries
- usually less damaging as it is so far deep under the surface
131
Underwater earthquakes:
They move the sea bed and displace water.
Cause Tsunamis
132
What year was the Hati earthquake?
2010
133
What's the name of the model that describes how air circulates between low and high-pressure belts?
Global atmospheric circulation model
134
What is the magma type for composite volcanos?
Andesitic
135
What is the magma type for sheild volcanos?
Basaltic
136
What type of radiation is emitted by the Sun?
Short wave radiation
137
What causes bigger tsunamis?
Shallow-focus earthquakes
| Deep-focus earthquakes
138
Are Earthquakes easy to predict, and why?
Cannot be easult predicted but monitoring certain signs like
- movements
- vibrations in Earth's crust
139
How are vibrations in Earth' crust measured?
Using seimoeters
140
What happens to rocks before an earthquake?
They crack and expand due to increased pressure
141
Can volcanic eruptions be predicted
Yes, if the volcano is well monitored
142
How do we know if a volcano is likely?
- tiny earthquakes
| - changes in the Volcano's shape
143
What are used to detect changes of temperature around a volcano?
Thermal imaging cameras
144
What long term planning can be done to help prepare for a tectonic hazard?(5 reasons)
- train emergency services
- buildings designed to withstand earthquakes
- educate population
- evacuation routes
- emergency supplies
145
Name 5 examples of short term relief that needs to be provided after a disaster?
- food,drink
- treat injured
- Prevent the spread of disease(recover dead bodies)
- rescue trapped people
- provide temporary supplies(gas, electricity, communications ect
146
What are our two tropical cyclone case studies?
Hurricane Katrina(USA) and Cyclone Nagis(Myanmar)
147
What is Hurricane Katrina's magnitude at landfall, and date?
Magnitude 3 and landfall and 2005
148
What forecasting did the USA have for Hurricane Katrina?
-sophisticated monitoring system
149
What warning and evacuation did the USA have for Hurricane Katrina?(3 answers)
- warning issued for: Alabama, Mississippi and Louisiana
- state of emergencies issued
- 70-80% of New Orelands residents evacuated
150
What flood defences did the USA have for Hurricane Katrina?
Flood defences(e.g embankments failed- 80% of New Orleans underwater
151
What were the enviromentwl impacts of Hurricane Katrina(2 answers)
- costal habitats damaged
| - oil spills
152
Two social impacts of the Hati earthquake?
- 250,000 injured
| - 3 million affected
