Atmospheric Disturbance Case Studies Flashcards
Moore Tornado, Oklahoma, USA, 2013 (HIC): MAIN FACTS
- Occurred on 20 May 2013
- This tornado appeared in an area that has been previously struck by a tornado in 1999.
- The tornado ‘touched the ground’ around 3pm in the afternoon.
- Mile wide tornado that has a category F5
- The area has been hit by 3 tornadoes in 2 decades
- A warning was issued 16 minutes before the disaster which saved around 1000 lives
- Geographically located where there is the collision of different types of air masses coming together at different times of the year
- Spring into early Summer = most active
Moore Tornado, Oklahoma, USA, 2013 (HIC): HAZARDS
Primary Hazards
- Tornado was on the ground for 45 minutes, leaving a path of devastation 27km long and 2.4km wide
Secondary Hazards
- Cars were tossed in the air and building facades were stripped
- Power lines were left lying on roads and pavements created tornadoes to movement and danger from power outages
Moore Tornado, Oklahoma, USA, 2013 (HIC): IMPACTS
- 25 people lost their lives.
- 237 injuries
- 2500 homes destroyed or demolished
- Flattened whole housing estates, reducing two and three-storey buildings to sticks
- Two primary schools were destroyed
- First school was completely demolished, but noone died. Second school had no shelter from tornadoes, so it caused the greatest loss of life.
- 10,000 people affected
- Gas and water supplies were cut
Moore Tornado, Oklahoma, USA, 2013 (HIC): RISK PERCEPTION
Oklahoma Department of Emergence Management advises people to:
- keep informed about the weather by listening to local weather forecasts and to have a bettery operated NOAA Weather Radio, which has a warning alarm feature
- plan well ahead, knowing what to do to keep safe
- get inside a strong building when a tornado threatens. go to the lowest floor, preferably a basement. keep as far away from doors, windows and outside walls as possible
- avoid being in a mobile home or vehicle
- cover up to protect from flying debris (hard hats)
Hurricane Katrina, Southern USA (New Orleans), 2005 (HIC): MAIN FACTS
- The track of the hurricane 23rd to 29th August 2005.
- Sixth-strongest Atlantic hurricane ever recorded and the third-strongest land-falling U.S. hurricane on record.
- Katrina developed as a tropical depression, approaching the southern tip of Florida from the south
east - Although it did not experience a smooth rise in strength, Katrina moved through levels 1–5 on the Saffir-Simpson scale as it curved across the Gulf of Mexico towards the Louisiana coastline around New Orleans.
- sea surface water temperature was at least 28°C, ideal for hurricanes to gather strength.
- it hit New Orleans with Category 4 strength on 28th August 2005, with the eastern side of the city worst hit
- the tropical storm traveled from the gulf of Mexico to Mississippi and then become a tropical depression when it reached Tennessee
Hurricane Katrina, Southern USA (New Orleans), 2005 (HIC): HAZARDS ON NEW ORLEANS
- Hurricane Katrina caused a storm surge (Sea level about 9 metres above normal)
- The intense LOW PRESSURE and strong winds allows sea level to rise, flooding coastal areas - several kilometers inland in some places
- Initially it was hoped that New Orleans had weathered the worst of Katrina, but within hours of the storm passing, it emerged that 4 key levees had been breached causing floodwater to pour into the city.
- Much of New Orleans lies below sea level.
- The city has a system of canals and levees topped with concrete floodwalls to keep water out.
- These are designed to withstand a category three hurricane, but when Katrina - a category four storm - hit, they were quickly overwhelmed.
- Within 24 hours, 80% of the city was flooded.
- Flooding affected large parts of the poor areas of the City in general
- Situation quickly deteriorated as it became apparent that thousands of people had been unable to evacuate or chosen to stay put.
Hurricane Katrina, Southern USA (New Orleans), 2005 (HIC): IMPACTS
- Economic impact >$150 billion
- Damages: $81.2 billion (2005 USD) (costliest Atlantic hurricane in history)
- Fatalities: ≥1,723 total
- 100,000 temporary homes needed
- A year on and still New Orleans is eerily empty. Of a pre-Katrina population of half-a-million fewer than 200,000 have returned.
Hurricane Katrina, Southern USA (New Orleans), 2005 (HIC): MITIGATION
1) Sanctuary within New Orleans - the Superdome
- As a huge sports stadium, sturdily constructed, this building seemed an excellent place to house those fleeing from the hazards.
- not far away to travel to
- it went extremely wrong. Crime, squalor and fear were reported, and conditions became so bad that on Saturday, 3 September the last 300 refugees were evacuated from that building.
2) Red Cross Effort
The American Red Cross set up 275 shelters in 9 states remarkably quickly, with more on standby.
3) Emergency services, the city authorities and the federal government
- About $1bn in relief meant for victims of Hurricane Katrina was lost to fraud
4) Repairing Levees
- By August 2006 –one year on, the city’s levees and floodwalls have been repaired to a standard equalling their prior condition.
- Despite this work, critics say not enough has yet been done to improve the city’s storm protection system.
Hurricane Katrina, Southern USA (New Orleans), 2005 (HIC): EVALUATION OF RESCUE EFFORT
- Even as the majority of citizens were evacuated from New Orleans, the numbers of people who choose to stay, the no. of people who wanted to leave but had no means of transport (primary the poor + black) and the late entry federal rescue workers = ↑ DR
- Policies aimed to attend to the living - to save those who could be saved - but came at the cost of leaving bodies for longer than was desirable or event decent
- People were stranded for days
Super-Typhoon Haiyan, Philippines, 2013 (LIC): MAIN FACTS
- One of the strongest ever-recorded typhoons to hit the Philippines on the 8th November 2013.
- It was classified as a super typhoon - a Category 4 or 5 typhoon on the Saffir-Simpson scale, when surface winds sustain at least 150 mph speeds for one minute, and it was the strongest ever recorded at landfall.
- It grew from a tropical storm as it moved westwards, stirring up 15-metre high wives
- It was at maximum intensity when it reached the island Guiuan
Super-Typhoon Haiyan, Philippines, 2013 (LIC): PREDICTION, MONITORING, PERCEPTION OF RISK
- Alerted by satellite images and the track of the typhoon, public storm warnings were issued and shelters opened, but there were not enough for everyone and some already damaged
- Many of the shelters were very basic and not well stocked with essential supplies
- Only half a million people were able to use them
- The government advised evacuation but did not make it mandatory so many stayed in their homes because they were afraid of looting
- The army, air force, navy and hospitals were on standby and disaster response teams were sent to areas expected to be affected
- Mayor of Guiuan saved many lives as he constantly urged the residents to evacuate
Super-Typhoon Haiyan, Philippines, 2013 (LIC): HAZARDS AND IMPACTS
- System moved so quickly across the country that rainfall totals did not produce devastating floods and landslides
- Mudflows and debris slides destroyed many buildings in Guiuan
- Nearly all the damage was caused by the Storm Surge when Haiyan moved to the islands of Leyte and Samar
- Tacloban, a city on land less than 5m above sea level, suffered the most
- The wall of water was over 7m high and almost caused total devastation
- 90% of buildings with wooden walls in the poorer parts of Tacloban were destroyed
- Many people drowned in the streets and many others were injured, as roads became rivers
- Buildings, power lines, rotten corpses, contaminated water supplies
- Survivors were left without shelters, food, water, sanitation and fuel
- The disaster relief failed due to breakdown in power + communications
Super-Typhoon Haiyan, Philippines, 2013 (LIC): LONG-TERM EFFECTS
- Mangrove forests were planted along the coast, replacing these destroyed from storm surges + wind
- Scale of disaster was large due to a 3X increase in the population of Tacloban in recent years
- After, many people moved to the city of Manila
- The growth of the economy slowed down temporarily due to agriculture being badly affected
