Hazards Flashcards
What is a natural hazard?
A natural hazard is a threat to people or property
What are the two main types of natural hazards?
Geological hazards - land and tectonic processes, volcanoes and earthquakes
Meteorological hazards - weather and climate, tropical storms and extreme weather
What factors affect hazard risk?
Vunrability- the more people there are in an area, the greater chance they’ll be affected
Capacity to cope- the better a population can cope with an extreme event, the lower the risk of them being severely affected
Nature of natural hazards - some can be predicted , some can’t , magnitude ect
What the primary effect of a hazard?
Immediate impacts
People injured killed, roads destroyed ect
What are the secondary effects of a hazard?
Happen later on
Often as a result of primary effects
Immediate responses of hazards include…
Evacuating people
Recover dead bodies
Treat injured
Provide food and drink, shelter to peo0le without homes
Long- term responses of hazards include..
Repair Homes or rehouse people who have lost their homes
Repair and rebuild buildings
Recconedr broken electricity, water and gas stations
Improve forecasting and evacuation plans
Boost economy eg. Promoting tourism
What is the order of the structure of the earth…
Inner core- 800 miles thick
Outer core- 1400 miles thick
Mantle- 1800 miles thick
Crust- oceanic and continental
What is the earths crust divided into ?
Tectonic plates
Why do the continental plates move?
Due to convection currents
What is the place that plates meet at called?
Plate margins or plate boundaries
3 types of plate margins
Destructive
Constructive
Conservative
What happens at the destructive plate margin?
Two plates move towards each over ,
Denser oceanic plate gets subducted under the continental one
Volcanoes and trenches occur here.
Nazca plate subducted under South American plate.
What is created when continental plates meet
Fold mountains
What is a constructive margin?
A margin where plates are moving away from each over
Maga rises from the mantle to fill the gap and cools, creating new dust.
Eurasian plate and North American plate moving away from eachove forming the mid- Atlantic ridge
What’s a conservative margin?
When plates move side ways past each over
Crust isn’t created or destroyed
Pacific and North American plate are moving in the same direction
When and where New Zealand earthquake happened?
22 nd feb 2011
7.8 magnitude
Primary effects of New Zealand earthquake…
2 people died
50 injured
Total cost of damage was 8.5 billion dollars
Secondary effects of New Zealand Christchurch earths quake…
Triggered 100,000 landslides , blocking roads
A tsunami occurred
Nepal earth quake. When? Magnitude? What boundary?
25 th April 2015
7.8 magnitude
On a destructive plate boundart
Primary effects of Nepal earthquake quake…
9000 people died 22,000 injured
800,000 buildings destroyed
4 mil left homeless
Secondary effects of Nepal earthquake…
Triggered avalanches which killed 18 people
Roads blocked by landslides
Lack or clean water
Imideate responses of the Christchurch earth quake
Tsunami warning
Emergency shelters
Power restored
Water supplies set up
International warships sent
Long term reposes of Christchurch earthquake..
Roads repaired within 2 years
5.3 mil in funding provided
Immediate responses in Nepal earth quake
People tried to recover the dead
Emergency shelters set up
Charities provided medicine
Long term responses of Nepal earth quake..
Water
Reasons people live near active volcanoes….
Tourism/ research
Containing many minerals
Good location / jobs
Earthquake proof buildings
Geothermal energy supply
Sulfur mining
How do we monitor tectonic hazards ?
We use seisomometres to observe temperatures and changes to earths environments. Check gas levels
How to we predict tectonic hazards?
Experts know where they are likely to happen due to siesmic machines detecting tremors in the earth
What is global atmospheric circulation?
Transfer of heat from the equator to the poles by movement of air
What is a tropical storm?
Hurricanes, typhoons,cyclones are very intense areas of very low pressure (rising air):. Usual 500-1000 km in diameter
Circumstances for a hurricane to form are..
Sea being over 26.5 degrees
Between Tropic of Cancer and tropic of Capricorn
Not at equator or 5 degrees north or south of it
Sea has to be at least 50 m deep where it forms
What’s the centre of the storm called?
How wide is it ?
What’s it causes by?
The eye
50 km across
Caused by descending air
What’s the eye of a storm surrounded by and what happens there?
The eye wall
Spiralling air and very strong winds (160mkoh)
What’s it like at the edge of a storm?
Wind speed falls
Clouds become smaller
Rain becomes less intense
A tropical storm case study is….
State date
Typhoon haiyan
8 th November 2013
Primary effects of typhoon haiyan
8000 killed
1 million homes destroyed or severely damadge
1.9 mil people made homeless
Electricity and water effected
Damadge costs where approximately 13 million
Secondary effects of typhoon haiyan..
Flooding triggered landslides
5.6 million workers lost their jobs
Lack of clean water caused outbreaks of disease
Immideate responses of typhoon haiyan…
Fishermen warned not to go to sea
PAGASA issued broadcast warnings 2 days before the flooods, evacuating nesrly 800,000 people
Philippines immediately declared a state of emergency
Long term responses of typhoon haiyan…
The un appealed for 300 million to help rebuilding and repair
Charities built storm resistant houses for those who lost their homes
Philoipemes tourism board encouraged people to visit the country. Tourism helped raise economy
What are the ways to reduce effects of tropical storms?
Prediction and monitoring
Planning
Protection
What does prediction and monitoring include ?
Storms can be monitored using satellite and aircraft
Predicting when and where a storm willl happen gives people time to evacuate buildings
What does planning include?
Governments planning evacuation routes
Emergency services can prepare for disasters
New houses not built in high risk areas
How could climate change affect tropical storms
Their distribution
Their intensity
Their frequency
6 types of weather hazards in the uk, impacts and examples…
Strong winds - damadge properties and disrupt transport.
Heavy rainfall- too much rain can cause flooding, recovery from flooding can cost millions of pounds
Snow and ice- schools and businesses forced to shut,this has an economic impact
Drought- water supplies run low causing economic impacts such as crop failures
Thunderstorms- lightning can cause fires damadgimg property and killing people
Heat waves- can cause breathing difficulties and exhaustion which can kill people
Cause study of an an area that flooded…
Somerset floods.
Dec2013-Feb2014
Why did Somerset flood so badly?
Rivers hadn’t been dredged in 20 years
Rain fell on saturated land.
Social impacts of the Somerset floods…
More than 600 homes flooded, people forced to evacuate
Major transport links such as train lines were closed or disrupted
Insurance prices rapidly increased and some residents were unable to insure their homes
Environmental impacts of the Somerset floods…
Crops destroyed as 11500 hectares were flooded
Standing water made ground toxic and unproductive for a year
Tonnes of mud and debris were left by the floods, damadgimg vegetation
Economic impacts of the Somerset floods…
Total cost of the damadge was estimated at over 80 ,million
Local companies lost more than 1.2 million in business
Loss of tourism cost the county 200 million
Management strategies that were used in Somerset to reduce flood risk.
Before flood- warning systems gave people to prepare and find emergency accommodation. People used sandbags to limit flood damadge on their homes
Since the flood- 100 million will be spent on turning temporary pump stations into permanent ones. Regular dredging of rivers
Building a tidal barrage at bridge water
Widening river sowys channel
What is the quaternary period?
The most recent geological time period, spanning from, about 2.6 million years ago to today.
What was the earths climate like before the quaternary period?
Warmer and more stable
What were global temps like in the quaternary period?
Global temp shifted between cold glacial periods that lasted around 100,000 years and warmer interglacial periods that last for around 10,000 years
Evidence for climate change …
Ice and sediment cores
Temperature records
Pollen analysis
Tree rings
How do ice and sediment cores show proof of climate change ?
Anew ice sheet is formed every year, scientists can drill back into ice and analyse the gasses in the ice to find out what the temp was in that year
Since when did temperature records start getting measured?
1850s
How does pollen analysis help prove climate change?
Pollen from a plant is preserved in a sediment, scientists know the condition that plants live in now, so if plants were similar they must have been around at a similar temperate period
How do Tree rings prove climate change?
Thickness of rings show what the temperature was like, the age of the temperature is decided by the number of rings
Natural causes of climate change…
Orbital changes- affects the solar radiation the earth receives
Volcanic activity- can causes short term cools of the earths atmosphere as the debris reflects the suns rays
Solar output- suns output isn’t constant
In what 4 ways are humans increasing the concentration of greenhouse gasses?
Deforestation-plants remove c02 from the atmosphere and store it
Cement production -when cement is produced c02 is released
Farming- produces methane, cows love to fart
Burning fossil fuels- c02 is released when fossil fuels like coal are burnt
Effects of climate change on the environment…
Melting ice caps and rising sea levels in Miami
Precipitation patterns are changing
Habitats like great barrier reef damadged
Climate change effects on people..
-Deaths due to heats increased
-Some areas are struggling to supply water to residents
-farming is affected, crops suffering such as wheat in Argentina
- more extreme weather leading to hazards
Strategies that try reduce the causes of climate change- the greenhouse effect
How much does the eu want to reduce carbon enissions by between 1990-2030?
Planting trees- increases c02
Carbon capture- capturing c02 and storing it deep underground
Alternate energy production-replacing fossil fuels with renewable energy
International agreements- eu aims to reduce carbon emissions by at least 40% between 1990 and 2030
How are people adjusting to the effects of climate change?
Changing agricultural systems- biotechnology used to create new crop varieties that are resistant to extreme weather
Managing water supply- rain water and waste water collected and recycled
Coping with rising sea levels-better flood warning systems and putting hard engineering in place
