unit 3 Flashcards
What is the definition of a climatic hazard?
“an extreme climatic/weather event that causes harm and damage to people, property, infrastructure and the environment”.
What are the climatic hazards associated with low pressure zones?
Tropical Cyclones
What are the climatic hazards associated with high pressure zones?
Drought
What are the five stages of the Park’s Model: The Disaster Response Curve?
- Hazardous geophysical event
- Search and rescue care
- Temporary housing and services
- Recovery
- Return to normal/Improvement
Which type of countries are more likely to see improvements after a climatic hazard?
More Economically Developed Countries (MEDC’s)
What is a tropical cyclone?
the generic term for a large low pressure system that forms over tropical/sub- tropical oceans
What are the severest conditions of a tropical cyclone?
winds that exceed over 150mph,
5 to 6 miles high
300 to 400 miles wide
At what latitudes to tropical cyclones tend to occur and why?
approx. latitudes of 8 to 20 degrees N/S of the Equator, this is due to the ocean temperature being above 27 degrees in these areas
What are the different names for Tropical Cyclones?
- Hurricanes
- Cyclones
- Typhoons
- Willy-Willies
Why do the northern and southern hemisphere experience the cyclone season at different times of the year?
this is because they have summer and winter at different times of the year, therefore means their temperatures vary from each other yearly
What happens during stage 1 of tropical cyclone formation?
- ocean is at least 27 degrees warm
- causes area of low pressure
- convectional clouds start to form in the troposphere
What happens during stage 2 of tropical cyclone formation?
- Due to the Coriolis effect, the winds in the low pressure system start to spiral, clockwise in the NORTHERN hemisphere and Anticlockwise in the southern hemisphere
- as water vapour condenses, releases latent heat, which causes an additional uplift of air
- more warm moist air is draw in at the base of the low pressure
What happens in Stage 3 of Tropical Cyclone formation?
- Providing that the low pressure system remains over an area of warm ocean, it will continue to grow, feeding off the latent heat being released by condensation
- tropical cyclone fully develops when the winds exceed 74 mph, at this point an eye will form
What is the eye of the storm?
Will develop in the centre of a tropical cyclone in which the cool risen air starts to descend back down through the atmosphere
How many categories of hurricane are there, what is the name of the scale used to determine this?
name = Saffir-Simpson Scale
5 categories, 5 being the worst with 155+ mph wind speed
What are the 4 hazards of a tropical cyclone?
1.Strong winds
2. Heavy rainfall, leads to extensive flooding
3. High seas - large waves up to 15m high
4. Storm surge
How much moisture can a tropical cyclone pick up per day?
2 billion tones of moisture
What is a storm surge?
a surge of water that is several meters high, can cause extensive flooding, damage to coastal regions (rise of sea level)
What is the case study for tropical cyclones?
Hurricane Katrina, USA 2005
How high was the storm surge in Hurricane Katrina?
approx = 8 meters
led to wide spread flooding, in New Orleans
How many people where killed by Hurricane Katrina?
more than 1,800
For every 1 millibar (Mb) drop in pressure how much does the sea rise by?
1cm
How does a storm surge happen?
high winds push sea water towards the coast and it piles up.
known as the barometer effect (what happens when you drink through a straw)
Why are storm surges often the greatest hazard associated with tropical cyclones?
severe, flash flooding, hard to prepare for and even harder to recover
leave a LONG TERM lasting impact
What are the economic impacts of tropical cyclones?
- damage to property
- disruption to economic activity
- increased insurance costs
- cost of clean up
What are the social impacts of tropical cyclones?
- loss of life
- injury/disease
- homelessness
- outward migration
- loss of jobs
- PTSD
What are the environmental impacts of tropical cyclones?
- contamination of fresh water bodies and land by sea water
- damage to coastal systems
- pollution
What are the political impacts of tropical cyclones?
- increased public expenditure
- criticism of political leaders
What other factors determine the impacts of a tropical cyclone?
- wealth of a country
- type of defences
- coastal topography
- population density
- storm strength
What category hurricane was hurricane Katrina?
Cat 3
What % of New Orleans was submerged under water?
80%
What was the economic cost of Katrina (including repairs and losses)?
$300 billion
In 2006, how much did the tourist numbers go down by in New Orleans compared to 2004?
63% decrease
How many oil platforms did Katrina destroy?
30
How much have insurance companies paid out over damage claims?
$40 billion
How many people lost their lives because of Hurricane Katrina?
1,833, third deadliest Hurricane in the U.S.A
How many people outward migrated due to Hurricane Katrina?
1.2 million people
What did the unemployment rate in Louisiana rise from before and after the Hurricane?
5.6% before
12.1% after
How many National Wildlife Refuges were closed due to Hurricane Katrina?
16
What were some of the environmental impacts of Hurricane Katrina?
flood waters that covered New Orleans were pumped into Lake Pontchartrain, which contained a mix of raw sewage, bacteria, heavy metals, toxic chemicals e.t.c
What were some of the political impacts of Hurricane Katrina?
- attention was drawn to the socio - economic groups
- the blame was attributed to ageing and neglected federal levee system
What was the difference between how Lakeview and the Lower 9th Ward after Hurricane Katrina?
Lakeview = a prosperous dominantly white middle class area (recovered)
Lower 9th Ward = a deprived district with a majority black community (not fully recovered)
What was a method of hard engineering that was used to manage the flooding after Hurricane Katrina?
New $15 billion flood protection strategies
The Hurricane and Storm Damage Risk Reduction System (HSDRRS) since 2011 to reduce the vulnerability of flooding in the New Orleans area
What was the long term responses that were put into place to prevent the risk of flooding again after Hurricane Katrina?
- higher and more resistant levees and flood walls were constructed throughout the region
- emergency pumps and canal closures were installed at the ends of the outfall canals
What was the soft engineering method that was put into place after Hurricane Katrina?
Wetlands restoration
due to severe dredging by oil and gas industries and draining swamps
What is Coast 50? What is the goal?
goal = towards a sustainable coastal Louisiana
- its a 50 year, multi-billion dollar strategic plan
- create small islands, plant Cyprus trees
- marsh grasses, reduce the rate of flooding
- wetland nursery, in the Lower 9th ward
From 2005 to 2014 what was the population change?
494,294 to 384,320
How did the population of the Lower 9th Ward changes from 2000 to 2010?
14,000 to 3,000
some entire streets occupied home
Why hasn’t the management dealt with the impacts of the Lower 9th Ward?
lack of funding, governmental support
hasn’t dealt with migration = many have never returned the city to only 30% of what it is
What is the case study for management of a Tropical Cyclone in a developing country and why?
Bangladesh
a low lying country of which 75% is below 10m above sea level and 80% is classified as a floodplain
What has the death toll decreased to between 1970s to the 1990s in Bangladesh (due to tropical cyclones)?
1970s = 5,100,000
1990s = 1,500,000
What is an example of a cyclone that hit Bangladesh in May of 2020?
Cyclone Amphan
What was the category of Cyclone Amphan?
Cat 5
winds were over 260km/h
5m high storm surge
To what extent were the impacts of Cyclone Amphan successfully managed?
Successful warnings let out early due to forecasting done by MEDC’s, which lead to early evacuations and reduced the loss of life
Following the evacuation orders what happened to those evacuated during Cyclone Amphan?
2.4 million people were moved
14,636 moved into permanent or temporary shelters in 19 coastal districts
What did the United Nations Development Programme report of the impacts of Cyclone Amphan?
- 26 people dead
- 55,667 houses were completely damaged
- approx. 149,000 hectares of agricultural land and fish farms damaged
What was the case study for the tropical cyclone that occurred in May 2008, in Bangladesh?
Cyclone Nargis
What was the category for Cyclone Nargis?
Cat 4
215km/h wind speed
4m storm surge
What was the death toll of Cyclone Nargis?
138,000 people
What was the number of homeless after Cyclone Nargis?
3.2 million people
What was the economic cost of Cyclone Nargis?
$10 billion
Contrast the emergency response of both Cyclone Amphan and Nargis in Bangladesh?
Amphan = evacuated before the storm
Nargis = Burma refused initial aid (2 days) and then only allowed those with visas
To what extent is it possible to minimise the impact of a tropical cyclone?
the impacts on life can be prevented, however the damage is less preventable
Can reduce the impact of the damage if people take their personal belongings with them, and they can be more prepared
What is an example of a high pressure hazard?
Drought
What are three effects of drought?
- loss of soil moisture
- depletion of ground water
- reduction of surface water stores
What are the potential impacts of drought on a developed nation?
economic loss, increase in imports = increased price
social
What are the potential impacts of drought on a less developed nation?
- starvation
- no income = life or death
- thirst
(affects more severely)
What is the definition of a water balance coefficient?
the difference between precipitation and potential evapotranspiration
How does a negative water balance work?
areas that suffer drought tend to be arid, areas with low levels of annual rainfall, and high levels of evapotranspiration
What is the definition of water vulnerability?
when water supplies may become contaminated by human activities
What is the definition of water stress?
demand for water exceed the available amount during a certain period
What is the definition of water scarcity?
not enough water to need the needs of the population
What are the causes of water vulnerability?
- demand exceed supply
- water infrastructure inadequate
- drought
- water pollution
What are the impacts of water vulnerability?
- conflict
- economic decline
- people can’t feed = crops
- diseases
- industrial output
What is the definition of physical water scarcity?
when there is not enough water to meet our needs
What is the definition of economic water scarcity?
occurs when human, institutional and financial capital limit access to water even though there is water in nature available to humans
What are the physical (environmental) secondary hazards of drought?
- falling water table
- loss of vegetation
- wild fires
- soil erosion
- damage to ecosystems
What are the human (social/economic) secondary hazards of drought?
- loss of income from agriculture
- reduced government income
- malnutrition
- illness from contaminated water
- outward migration
- increase in food prices
How can we reduce water demand?
- ration
- limit use by farms
- encourage use of dishwashers
- don’t sell water bottles
How can we increase water supply?
- build reservoirs
- desalination
What is the case study for drought, and what affects its climate?
Ethiopia
levels of precipitation related to topography and position of the ITCZ
What are the rainfall patterns like in Ethiopia, how much it receives and when?
Typically receives around 600mm annually
2/3 of this received between July and August
