Hazardous Earth Flashcards
1
Q
Explain global circulation in 3 steps
A
- Warm air rises at the equator (low pressure)
- Cool air falls (high pressure)
- As the air falls it warms again and flows back to complete the cycle
2
Q
What do high pressure areas look like?
A
Clear skies and little precipitation
3
Q
Give 2 ways how ocean currents transfer heat
A
- The wind (circulation cells)
- Density differences due to differences in water temperature and salinity
4
Q
What is the biggest cell?
A
Hadley Cell
5
Q
Name the 3 cells
A
- Hadley
- Ferrel
- Polar
6
Q
Where is the hadley cell located?
A
Near the equator
7
Q
Where is the Ferrel Cells located?
A
30 degrees north and south
8
Q
Where is the polar cell located?
A
South and North Pole
9
Q
8 points
What are the natural causes of climate change?
A
- Solar Variation
- Eccentricity
- Tilt
- Wobble
- Volcanism
- Asteriod Collisions
- Orbital Changes (Milankovitch cycles)
- Ocean current changing
10
Q
Explain how volcanoes cause climate change
A
- Eruption = CO2 = GHG
- Aerosols eg sulfur dioxide, they react with water vapour to form sulfate aerosols. They reflect sunlight which have a cooling effect on the Earth
11
Q
Explain Solar variation
A
Amount of energy changes over an 11 year cycle. Periods of lower solar activity lead to glacial periods and those with higher activity lead to warmer interglacial periods.
12
Q
Explain sun spots
A
Black areas on the sun, spots tell the Sun is more active than usual, more spots means more solar energy fired out from the sun
13
Q
Explain Orbital Cycles
A
Orbit is sometimes circular or ellipse (oval). Circle (more heat), Oval (less heat). Changes due to wobble
14
Q
Give ways we can find evidence of climate change
A
- Tree rings
- Sea level Rise
- Historical Sources
- Pollen Records
- Ice Cores
- Melting Ice Sheets
15
Q
Explain Tree rings
A
Rings are added every year of growth, narrow means a cooler, drier year, thicker means warmer and wetter
16
Q
Explain ice cores
A
Ice is drilled to measure C02 trapped. Trapped air bubbles, composition of gases is analysed and tells levels of gases
17
Q
Explain historical sources
A
Paintings, diaries, documentaries, weather reports
18
Q
What is the greenhouse effect?
A
- Natural process where gases in atmosphere trap heat from sun.
- Short wavelengths from the sun
19
Q
What is the enhanced greenhouse effect?
A
- Unnatural heating caused by humans
20
Q
List 4 human causes of climate change
A
- Transport
- Industry
- Farming
- Deforestation
21
Q
What is the glacial or Ice Age?
A
When the temp was cooler for longer periods, more of Earth is covered in ice
22
Q
What is interglacial?
A
Now, warmer period
23
Q
What are the possible consequences of global warming?
A
- More droughts, lasting longer
- Loss in biodiversity
- Loss of glaciers - water supply probs
- more destruction - extreme weather
- sread of diseases
- Changes in farming
- Coastal flooding
- More floods
24
Q
6 points
What is needed to form a cyclone
A
- 26.5 degree water
- Cluster of thunderstorms
- Earths rotation - Coriolis Effect
- Light winds causing air to rise
- Time of year - Late summer early autumn
- Tropic of cancer and capricorn
- 70m deep
- trade winds - warm as they blow towards equator
25
What is a cyclone?
Fast-moving rotational storm formed in the ocean, has strong winds and is associated with heavy rainfall and flooding.
26
Give 3 words for cyclone
* Willy Willy
* Typhoon
* Hurricane
27
# 5 points
What are the impacts of tropical cyclones?
* Storm surges
* Coastal Flooding
* Heavy Rainfall
* High winds
* Landslides
28
What way do hurricanes rotate/move in the North and South hemisphere?
North - clockwise
South - Anticlockwise
29
Environmental/ physical factors that make countries more or less vulnerable
* Low-lying coastal areas
* Near the coast
* Soft permeable rock - landslides are likely
* Within the tropics
30
Social factors that make countries more or less vulnerable
* Poor, lower class
* Old people
* People are of minority races
* No response systems prepared at a community/national level
31
Economic factors that make countries more or less vulnerable
* Rich developed countries have better prediction, protection and evacuation technology
* No investment in tracking
* No investment in coastal defences
* No investment in sturdy buildings
32
Key points to include in comparison of cyclones (vulnerability)
* Development
* Capacity to cope (how quickly they can recover)
* Buildings
* Money
* Preparation, Prediction, Adaptation
33
What is GIS?
Geographical Information Systems - maps are digital maps that have layers of data added to them. GIS maps can be changed to show specific information about a place.
34
What 4 things have to be considered in order to prepare or respond to a TC?
* Prediction - give warning
* Protection
* Preparation
* Planning - evaluate past evens to find solutions
35
Is a hurricane low or high pressure?
Low
36
What is weather forecasting?
Measuring atmospheric pressure using bouys/boat data
37
Positives of weather forecasting?
* Storm surge predictions
* Sends quick warnings to countries
38
Negatives of weather forecasting?
* Only takes local readings
* Expensive
39
What is satellite tracking?
Large areas of ocean can be measured, satellites in space find formations of cloud formations
40
Positives of satellite tracking?
Tracked in real-time
41
Negatives of satellite tracking?
* Hard to spot until it has an eye
* Radars (track precipitation levels) are expensive
42
What are warning systems?
Gives information and guidance on what to - from TV, radio, internet
43
What are the positives of warning systems?
Most people have social media so they would see warnings
44
What are the negatives of warning systems?
Not everyone has daily access to a phone/ internet
45
What is an evacuation strategy?
Emergency shelters, evacuation points, trains emergency services how to react to reduce deaths
46
What are storm surge defences?
Government likely to have invested in defences
47
Negatives of storm surge defences?
* Developing countries cant afford defences that are strong (they use embankements that arent effective
48
Where was Hurrican Katrina?
How many deaths?
Category?
Causes of deaths?
1. Developed country - USA
2. 1836 deaths
3. Category 3
4. Failed storm surge defences, levees breached, shelters lacked food, evacuation had problems
49
Improvements since Hurricane Katrina
1. Levees made much higher and stronger
2. Funding spent on search and rescue teams - emergency text messages
3. Lake Vorgne surge barrier built to protect New Orleans
4. All these costed $14 billion
50
Name the layers of the earth
1. Inner core
2. Outer core
3. Mantle Crust
51
What is the asthenosphere?
* Solid
* Upper part of mantle where rocks flow
52
Temperature of the mantle + characteristics
* 500 - 900
* completely molten rock - magma
* rocks at the top are semi-molten rock = asthenosphere
53
What is the temperature and material of the outer core?
* Liquid iron and nickel
* 4000 - 6000
54
What is the temperature and material of the inner core?
* Solid iron due to high pressure
* Iron and nickel
* 5000 - 6000
* energy generated by radioactive decay
55
How does convection work in the tectonic plates?
1. Core heats molten rock in matle to create convection current
2. Heated rock from mantle rises to Earth's surface
3. At surface, convection current moves the tectonic plates in the crust
4. Molten rock cools and flows back to core to be reheated
56
Properties of continental crust
* Less dense than oceanic
* Granite
* Never sinks so is never destroyed
* cant sink
57
Properties of oceanic crust
* More dense than continental
* Basalt
* Eventually sinks into the mantle so continually renewed
58
Convergant/ Destructive plate boundaries
* 2 plates collide - oceanic and continental
* Denser oceanic is forced under
* 1 plate flows beneath another (subduction)
* Many earthquakes and volcanoes
* If 2 continental plates collide = mountain ranges
59
Divergant/ Constructive plate boundaries
* Rising convection currents cause plates to move apart
* Magma rises to fill in gap
60
Conservative plate boundaries
* 2 plates slide past each other at different speeds
* Earthquakes
* Opposite or same direction
* Friction and pessure build between the plates and then they slip (earthquake)
61
Shield volcanoes
* Found in constructive plate boundaries/ hotspots
* Formed by eruptions of lavahave gentle sloping sides with wide base
* erupts frequently but not violently
* has basaltic magma - very hot, low silica and gas content
62
Lithosphere
Uppermost layer and is split into continental crust and ocean crust
63
Composite volcanoes
* Found on destructive p b
* Formed by eruptions of lava
* Steep sloping sides with narrow base
* Layers of thick lava and ash
* Has andesitic magma (less hot than basaltic) contains lots of silica and gas
* Erupts infrequently not violet
64
Epicentre
point of the surface directly above the focus
65
Focus
central point of earthquake deep under surface
66
What scale is used to measure magnitude?
Moment magnitude scale - old = richter scale
67
Deep-focus vs shallow-focus
Deep-focus is far away from the earth's surface and shallow-focus is close
68
How are hotspot volcanoes formed?
* Magma plume rises and breaks throught oceanic crust, forming a shield volcano
* Over time, plate moves away from the hotspot as plates constantly move - means volcanoes move away
* New volcano created in position of the magma plume which doesnt move
* Forms: extinct (oldest island), dormant and active (youngest island)
69
Primary hazards of volcanoes
* Toxic gases
* Lava flows
* Lava bombs
* Pyroclastic flows
70
2ndary hazards of volcanoes
* Acid rain
* Lahars
* Landslides
71
What boundaries make earthquakes?
* Divergant/constructive - small by friction
* Conservative - rare but v destructive
* Convergant/destructive
72
What boundaries make volcanoes
* Divergant/constructive
* Convergant/destructive
* Collision - v rare
73
What causes tsunamis
Earthquakes caused by plate movement
74
What movement of air generates wind?
Air always moves from high to low pressure
75
What is the Coriolis effect?
* They influence prevailing winds
76
Water cycle stages
1. Evaporation = water heated by sun, turning into water vapour
2. Transpiration - plants release water vapour too through leaves
3. Condensation = Water vapour rises and cools into tiny droplets = clouds
4. Precipiation = once clouds become heavy with water droplets, they release the water in the form of rain/snow
5. Infiltration and runoff = some water seeps into the groud (infiltration), some flows over land into rivers (runoff)
77
What happens to density as depth increases in the earths structure
Increases so inner core in the most dense
78
How do changes in the Earths orbit/ Milankovitch cycles affect climate change?
* Earth's orbit changes between elliptical and circular
* axis wobbles, straighten, wobbles
* takes a long period of time
* changes temperature
79
How do asteroid collisions affect climate change?
cause cooling as large quantities of ash and dust to be kicked up into the atmosphere
80
What latitudes is the Hadley Cell found in?
Between equator and around 30 N/S
81
What latitude is the Ferrel cell found between
30 NS and 60NS
82
What latitude is the Polar Cell found between?
Betwen 60 NS and the poles 90NS
83
Where are the high pressure belts
* Poles
* 30 degrees latitude north and south
84
Where are the low pressure belts?
* Equator
* 60 degrees north and south
85
Why are pressure belts important?
Surface winds blow from high to low pressure
86
What are surface winds?
Winds close to the ground
87
What are the doldrums?
Areas of low pressure at the equator
88
What are trade winds?
Blow wind from the hot desert to the doldrums area
89
Name greenhouse gases
* co2
* methane
* nitrous oxide
* chlorofluorocarbons (CFCs)
90
What do CFCs do?
* depleting ozone layer
* break down ozone molecules
91
What is a downside of using computers to model predictions about rainfall infleunced by climate change?
They have some element of speculation
92
Explain how pollen records provide evidence for climate change
* Plants produce lots of spores of pollen
* get trapped and stuck in mud
* every type of plant has diff shaped pollen
* ppl work out past climates bsed upton the plants that grew in the past
93
Process of the formation of tropical cyclones
1. Warm moist air rises
2. Rising warm air meets cooler air
3. Rising air replaced by moist cool air
4. If this is a long process, storm = more intense + longer lasting
5. Coriolis effect of wind, then eye of the storm
6. Storm driven by trade winds
94
How do you measure tropical storms? Name its categories
Saffir-Simpson scale
Category 1 to 5 (intense)
95
Safety from TC
* Tidal gates - sloed as a hurricane approaches
* Houses can be reinforced or built on stilts
* shutters and hurricane proof glass can be installed
* sanitation improved
* financial aid
96
What are the 2 different types of destructive plate margins
* destructive convergent zones
* destructive collision zones
97
What are destructive convergent zones?
* Meeting of oceanic and a continental plate
* oceanic sinks/ subducts under contintenal
* creates an area of deepwater = ocean trench
* oceanic plate melts = magma = erupts as a volcano
* plates can get stuck togther = pressure = earthquake
98
What is a destructive collision zone?
* 2 continental plates collide
* forming mountains
99
What are hot spots?
Area with thin crust that magma can burst through the surface
100
3 states of a volcanoes
* active
* dormant - havent erupted for some time
* extinct
101
What causes a wave to increase in height when it reached land?
* experiences friction with sea bed
* increase in height
* tsunamis can go far inland
102
Which tectonic location where volcanoes are never found
conservative
103
why TC form between latitudes 5 and 30 north and south
warm ocean over 26.5, causes warm air to rise
TC needs coriolis force - means they form away from the equator
104
Earthquakes at conservative plate boundaries
earthquakes occur as plates attempt to slide past each other - causes friction to occur = stress built up as plates try to move past each other
105
Mantle layers
2 layers
Thinner asthenosphere - partly molten layer under lithosphere
low mantle - solid
106
core
* 2 layers
* outer core - liquid
* inner core - solid due to high pressure
* both iron and nickel
107
How is the earth heated?
* radioactive decay in core and mentle + convection currents caused by the geothermal energy
* rising heat create plumes which bring magma to surface
108
Port-au-Prince earthquake Haiti
* Magnitude 7.0
* 300,000 deaths
* 1 million homeless
* buildings collapsed
* blocked roads, affects spread of aid
* cholera outbreak - 8000 died
* 1 in 5 jobs lost from clothing factories
109
explain 1 diff between the type of volcanoes found at divergent and convergent plate boundaries
* Divergent PB Volcanoes are less steep due to runny lava which travels a greater distance before it solidifies
* Convergent PB volanoes are cone shaped because divergent have less viscous lava because it has a lower gas content
* More explosivity at divergent due to magma having lower gas content and it being less viscous
*
110
Where are volcanoes only formed?
* destructive
* constructive
111
How are destructive volcanoes formed?
1. Oceanic plate is denser so it subducts beneath continental plate into the mantle
2. Due to heat and pressure it melts into a pool of magma
3. Magma rises through cracks in the crust called vents
4. forms composite volcanoes
112
What PB do composite volcanoes form on
destructive
113
What PB do shield volcanoes form on?
constructive
114
How are constructive volcanoes formed?
1. The 2 plates pull apart
2. magma rises in between to fill in gap
3. creates shield volcanoes
4. eg hawaiin islands
