storm hazards

Question 1

how are tropical storms formed

Answer 1

• Hurricanes need a lot of heat to form, which is why they usually occur over tropical seas (at least 27°C).
• The sun is close to the equator, providing energy to heat the ocean.
• The warm ocean heats the air above it causing it to rise rapidly.
• Water evaporates quickly from the hot surface of the ocean, so the rising air contains great amounts of water vapour.
• The rising air starts to spin (anti-clockwise in the northern hemisphere)
• The centre of the storm - the eye - is calm.
• As the air rises it cools, condenses and forms towering cumulonimbus clouds.
• The rapidly rising air creates an area of intense low pressure. The low pressure sucks in air, causing very strong winds.
• they are driven by prevailing winds
• Once the storm moves over land it starts to lose energy and fades.

Question 2

where do tropical storms occur

Answer 2

they occur between the tropics of Cancer and Capricorn which are 23.5 degrees north and south of the equator

Question 3

5 hazards associated with tropical storms

Answer 3

-high winds: can travel out 300 km/h+
-average winds are 120km/h
destroy buildings
uproot trees

• storm surges(large rise in sea level): caused by high winds pushing water at high tides towards the coast in low pressure conditions
• heavy rain: caused by warm, moist air as it rises and cools
• flooding: caused by heavy downpour which causes river discharge to increase

-landslides: water infiltrates soil and rock making it less stable
90% of landslides are caused by heavy rainfall each year

Question 4

short term responses to tropical storms

Answer 4

evacuations

Question 5

hurricane case study
location
date
category

Answer 5

USA hurricane Sandy
22nd October 2012- 2nd November 2012
category 3

Question 6

hurricane sandy pattern

Answer 6

• started off the coast of Africa
• travelled north west across the Atlantic ocean through the Caribbean
• reached the east coast of the USA

Question 7

how are tropical storms measured

Answer 7

• classified using the Saffir-Simpson Scale which is based on wind speed and estimated damage
• 119km/h(category 1)
• category 5 is the strongest and category 1 is the weakest

Question 8

frequency of tropical storms

Answer 8

• around 100 per year
• some never reach land
• 5.9 become actual storms
• storms in the northern hemisphere occur between june and november
• storms in the southern hemisphere occur between november and april
• tropical storms are irregular
• they can be identified with satellite imagery allowing them to be predicted
• no evidence for increasing frequency or intensity
• 9/10 largest storm have occurred in the last 2 decades

Question 9

6 social impacts of the hurricane sandy

Answer 9

• 433 deaths in total
• 147 direct deaths
• 72 in the USA
• 54 in Haiti
• 11 in Cuba
• 215 patients evacuated from the New York University Langone Medical Centre due to power failure
• 8.5 million homes and businesses left without power
• supermarkets ran out of essentials in Washington DC
• marathon cancelled resulting in a loss of income
• 32 million forced out of their homes temporarily or permanently

Question 10

4 economic impacts of the hurricane sandy

Answer 10

• caused $71 billion in damages
• New York’s economic loss of $18 million
• 18,000 flights cancelled
• crops lost resulting in an economic loss for farmers

Question 11

6 environmental impacts of the hurricane sandy

Answer 11

• shanty towns in Haiti washed away
• fallen trees and floods affected wildlife habitats
• untreated sewage washed into public drinking water
• more than 70% of crops in south Haiti destroyed
• transport infrastructure destroyed
• 10m of beach lost in parts of New Jersey
• winds up to 185km/h

Question 12

what prior management did the US put in place for hurricane sandy
(4 points)

Answer 12

• the USA national hurricane centre predicted and monitored the hurricane path
• centre issued warnings to local authorities
• police evacuated thousands of people
• President Obama signed for emergency declarations

Question 13

3 short term responses for hurricane sandy

Answer 13

-local authorities issued warnings
-satellites used to monitor hurricane
-$50.5 billion hurricane sandy relief bill signed by president Obama
-

Question 14

cyclone case study
name
location
date
category

Answer 14

cyclone Nargis
bay of Bengal, Myanmar
may 2nd 2008
category 4

Question 15

cyclone Nargis path

Answer 15

• formed in the bay of bengal in the last week of april 2008
• as it approached Myanmar it strengthened to a category 4
• may 2nd it hit Myanmar with wind speeds of around 215km/h and a storm surge of 5m

Question 16

7 social impacts of cyclone nargis

Answer 16

• estimated death toll of 138,000
• 50,000 people still missing
• lack of food and water for survivors
• disease outbreak caused more death
• 2.4 million severely effected
• 1,163 temples destroyed
• 1 million+ left homeless

Question 17

3 economic impacts of cyclone nargis

Answer 17

• $10 billion in damages
• flooding of rice fields cost people their livelihoods and income
• 75% of buildings collapsed

Question 18

5 environmental impacts of cyclone nargis

Answer 18

• rice fields flooded on the Irrawaddy delta
• 2008 and 2009 harvest destroyed
• strong winds up to 217km/h
• 7.6m storm surge
• flood waters moved 40-50km inland

Question 19

what prior management did Myanmar put in place for Cyclone Nargis
(3 points)

Answer 19

• no dedicated hurricane monitoring system
• Indian weather agencies warned Myanmar government 48 hours before the cyclone hit
• no emergency plans, evacuations or early warning systems

Question 20

long term responses to hurricane sandy

3 points

Answer 20

• 2013: New York - rebranding ‘a stronger more resilient new York’ which was a plan to rebuild impacted communities
• USA invested in flood prevention and coastal protection schemes
• August 2013 the Hurricane Sandy Rebuilding Task Force released the report Hurricane Sandy Rebuilding Strategy

Question 21

how vulnerable was the USA to Hurricane sandy

4 points

Answer 21

• earthquakes and hurricanes had struck before so people had experience
• safe homes program in south Carolina decreases vulnerability for home owners
• in north Carolina houses sat on dunes making them more vulnerable as the dunes eroded

Question 22

5 short term responses to cyclone Nargis

Answer 22

• initially the government refused international aid
• 7th may aid was accepted
• aid workers were not allowed in until the 19th o may
• U.K gave $17 million in aid and an international relief team
• USA donated $41million and sent help form the red cross

Question 23

5 ways cyclone Nargis has affected Myanmar

Answer 23

• began collaborating with other countries
• improved national forecasting
• 87% of people have smart phones and receive warnings via an app compared to 3% in 2008
• 2010 citizens were able to vote - country had its first elected leader in 2 decades
• joined Paris agreement on climate change

Question 24

how has hurricane sandy affected the USA

3 points

Answer 24

• 1 in 5 families had not returned home
• 1/2 of New Jersey residents are unhappy with sate recovery
• 1/3 admit that they now struggle to pay for food, fuel and bills

Question 25

response and risk management to storm Hazards: prevention

Answer 25

- in current climate and weather conditions tropical storms cannot be avoided - strategies to mitigate climate change could prevent higher category storms

Question 26

response and risk management to storm Hazards: preparedness

Answer 26

- awareness via education of what do in the event of a tropical storm - evacuation plans and training - satellite image tracking manage areas at risk - storm warning system and television broadcasts tracking the storm

Question 27

response and risk management to storm Hazards: mitigation

Answer 27

- search and rescue, emergency aid, evacuation - strengthening the home with door barricades, roof strengthening - clearing loose debris before storms.

Question 28

response and risk management to storm Hazards: adaption

Answer 28

- move away from areas at risk - design buildings to withstand high winds and flood damage - flood defenses like houses on stilts, coastal walls, river levees

Question 29

5 ways Myanmar was vulnerable to cyclone Nargis

Answer 29

- country was suffering from 5 years of internal conflict - only 2.2% of Myanmar's GDP went towards healthcare in rural areas - poor sanitation in rural areas - 1/4 households live below the poverty line - deforestation of Mangroves on coastline made the storm surge worse

Question 30

tropical storm description

Answer 30

- low pressure environments that form between the tropics - up to 700km in diameter - eye is calm - sinking air - eyewall - most destructive - cloud banks

Question 31

conditions needed to form tropical storms

Answer 31

- waters at least 27 degrees Celsius - source of heat and water - ocean depth of at least 50m - provides latent heat - wind direction needs to be uniform - allows intensity and height to grow - atmospheric instability - Coriolis effect/ rotation of earth- doesn't occur at equator