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