Hazardous Environments

• Volcanic Primary Hazards - Lava

  Lava Flows - Shield, Basic, more threat to property than human, up to 50km/h, Hawaii has been erupting since '83 destroyed 187 houses but no deaths
• Volcanic Primary Hazards - Ash and tephra 


  Shield, basic

  Tephra is just bigger volcanic ash

  Finest ash can be carried high in the atmosphere and disrupt travel as well as the stratosphere and affect world weather patterns such as Mount Pinatubo, Philippines - evacuation happened prior to explosion due to intense monitoring

  Doesn't cause many deaths but can if respiratory problems

  Agri problems can also occur due to damage of crops such as in Washington when Mount St Helens erupted
• Volcanic Primary Hazards - Pyroclastic Flows 


  Composite, acid

  Most dangerous when directed sideways by lateral blast

  Kills 1/2 of those who die in eruptions such as Mount St Helens, it killed anything living in a 25km radius
• Volcanic Primary Hazards - Gases + Monitoring


  Composite, acid

  Produce water vapour, CO2, sulphur dioxide and carbon monoxide

  Lead to suffocation, Lake Nyos, Cameroon killed 1700 people

  Monitoring of Mount Pinatubo allowed 10km radius danger zone around volcano due to a steam blast then used instruments to monitor the volcano and issued urgent warnings which allowed evacuation
• Volcanic Secondary Hazards - Lahars


  Composite, acid

  Second greatest threat to human life

  Form with water mixing with loose volcanic material

  Can be as fast as 65km/h and travel far

  Eruption in Columbia killed 23 000 people
• Earthquakes primary hazards - Aftershocks 


  Occur after main shock in days or months - Christchurch, CTV killed 184 people just from aftershocks - Seismometers, measure and detect earthquakes and covert into data to be put on a computer to determine where and how big earthquake will be.
• Earthquake hazard - Landslides and Tsunamis 


  Occur due to loss of strength on slope due to shaking and earthquake below the sea cause the sea bed to rise - Boxing Day tsunami in the Indian Ocean killed 1 275 000 in several countries - Hazard mapping, shows areas which are likely to suffer from earthquakes, landslides, tsunamis
• Earthquake hazard - Disease 


  Crowding conditions in temporary settlements and the lack of access to necessities such as clean water can increase transmission of disease - Haiti spread of cholera due to open sewage systems - Education and Evacuation can mean preparedness is increased - 1st September is disaster prevention day in Japan
• Earthquake hazard - Soil liquefaction 


  Strength and stiffness of soil is reduce due to shaking by earthquakes which can lead to buildings collapsing, pipes breaking which can create fires - San Fran, fires broke up due to broken mains - Land use zoning, oil storage for example is placed away from homes and are built on solid rock to prevent this, any land that is liquefied is used as nature reserves or playing fields and is not built on
• Mass movement types - Heaves 


  Soil creep

  Slowest form of mass movement

  Move downwards on slope causing soil to ripple

  Cohesive material
• Mass movement type - Flows 


  Mudflows

  Rapid movement

  Soil mixed with water

  Steep slopes
• Mass movement type - slides 


  Section of hillside detaches itself and slides

  Landslide
• Mass movement types - Falls 


  Rock falls

  Steep slopes on bare faces
• Mass movement - causes and management - Steepness


  Vargas, Venezuela had oversteepened hills causing mudflows due top rainfall too - excavating and filling steep slopes, reduces the impacts of gravity - In Hong Kong private landowners must comply with regulations if not 50 000 fine and a year of prison, reduced landslides by 50%
• Mass movement - causes and management - Rain fall 


  Vargas, Venezuela had a 52 hour span of rain fall which ended up being 91.1 cm, this created instability and mud flows - Surface drainage systems with maintenance can be introduced in Hong Kong they have man made slopes with intercepting and direction methods for the water - Boreholes can indicate the water content in the ground and the pressure it is exerting
• Mass movement - causes and management - buildings 


  Campania, Italy has an uncontrolled amount of roads and buildings being built such as 217 000 homes without the correct foundations or drainage. Building on top of the hill puts pressure on the hill and make it more vulnerable but also allows the house to be more vulnerable - Landslide hazard mapping, using previous knowledge snd classify areas of high and low susceptibility.
• Mass movement - impacts on lives

  Vargas - displaced 75 000 people, necessities all disappeared such water, electricity, phone lines, up to 50 000 deaths, 1000 bodies recovered, 70% of population had to live in one small area
• Mass movement - impact on property 


  Vargas - 8000 homes destroyed, 700 apartment buildings destroyed, up to 3.5 billion worth of damage
• Management of Volcanoes - Mount Pinatubo 


  Monitoring and prediction - small steam blast caused a 10km radius issued, used instruments to measure activity of volcano, issued urgent warnings

  Preparedness - issued urgent warnings and evacuation to happen, forecasts allowed an estimate of 5000 to 20 000 saved lives, this experience will also help future predictions

  Prevention of impact of hazards - prevented property losses of at least 250 million pounds
• Hazards of tornadoes 


  Strong wind - 200+mph, Moore Oklahoma

  Flying debris

  Thunderstorm hazards, rain, thunder, hail, lightning
• Prediction and Monitoring of Tornadoes 


  Computer programs - analyse doppler radar for forecasters to identify weather

  Meteorologists - analyse doppler radar to look at rotation of mesocyclone to issue warning

  Storm spotters - trained to spot tornado conditions and report to national weather

  Barometers - measure air pressure if low = tornado

  Turtles - measure all conditions

  Tornado watch
• Impacts on lives - tornado

  Moore, OK 24 deaths, 7 children

  Doctors and nurses had to be brought in

  No schools and medical centres
• Impacts on property - tornado 


  Moore, OK, 1150 homes destroyed

  Schools and medical centres destroyed

  2 billion dollars worth of damage
• Formation of tornadoes 


  Air masses meet

  Supercell thunderstorm forms

  Wind sheer pushes it up and rotates

  Heavy rain pushes it down

  Pulls in warm moist air and wall cloud created

  Updraft gets stronger forms tornado

  Cold air cuts of warm air tornado dies
• Formation of hurricanes 


  Occurs near equator where seas are 26-27 degrees

  Sea absorbs sun's energy

  Air above sea then rises creating low pressure

  Air cools and condenses into water vapour and then droplets

  Large clouds forms and intense rainfall

  Air carries on blowing high to low pressure creating vacuum and strong winds

  Spirals upwards

  Hurricane carries on moving till it reaches land and loses energy
• Hazards from hurricanes 


  Strong winds 75 mph - Typhoon Haiyan 323km/h

  Coastal and river flooding - Typhoon Haiyan floods destroyed homes

  Landslides

  Storm surges, responsible for 90% of deaths caused by sea levels rising - Typhoon Haiyan 7m high waves and 30 000 boats destroyed
• Effect of global warming on hurricanes 


  Increase intensity by up to 11%

  Occurrence will increase

  Rainfall rates increase

  Sea level rises higher = bigger storm surges
• Management of hurricanes - TH -Preparedness


  Education and awareness campaigns thanks to Philippines meteorological agency broadcasting warning two day before, poster, radio, tv campaigns for instructions, evacuation plan, turn off utilities
• Management of hurricanes - TH -Prediction


  Proven to be effective as allow evacuation of 750 000 residents, satellites observe cloud formation over sea, radar gives images about rainfall, aircraft fly through the storm to collect pressure levels and wind speed
• Management of hurricanes - TH -Prevention


  Hard to prevent, cloud seeding, silver iodine into hurricanes causing rainfall to occur over the sea less damage on land
• Management of hurricanes - TH - Mitigating


  • Soft engineering, importance of coral reefs for storm surges
  • Hard engineering, making homes more resilient, immediate aid from government and long term from countries such as the UK who provided food shelter medicine to 800 000 victims and 480 million pound from United Nations
• Primary impacts of hurricanes

  1.9 million left homeless and more than 6 000 000 displaced

  7000 deaths

  Tacloban's city airport destroyed

  Widespread floods - causing oil spills
• Secondary impacts on Typhoon Haiyan

  Overall economic cost was about 5.8 billion dollars

  Six million workers lost their jobs

  International trade and farmers ruined due to crops destroyed

  Business and tourism decrease due to closure of airport

  30 000 boats destroyed ruining fishing industry