1.2 Tropical cyclones

Activity 1:

To do research on the effect that tropical cyclones have

[lo 2.1]

Read the information above on Demoina and make a list of the consequences of tropical cyclones. Look in newspapers and other sources of information for articles on tropical cyclones so as to extend your own list.

Why do tropical cyclones cause extensive flood damage but relatively little storm wind damage to an area?

What is meant by the “eye” of a tropical cyclone?

3. Why some people are at a higher risk to be affected by tropical cyclones than others

Tropical cyclones also cause great damage in the developed parts of the world, but they are usually not as disastrous. Communication systems are well developed and a large percentage of the population is thus aware of the approaching danger. They can take precautionary steps in time or evacuate the area. The construction of their houses and other buildings also makes it more likely that they will be able to withstand the storms.

However, a tropical cyclone can have very serious implications in the developing parts of the world. Firstly , these areas are densely populated and great numbers of lives can be lost, because many of these people also live in less desirable, more dangerous areas. Secondly , their houses are also often poorly constructed, which means they can be severely damaged or even destroyed during such a storm. Thirdly , these areas do not have good infrastructures which could limit or decrease the effects of such a disaster. Thus paramedics and other emergency services personnel cannot reach these people quickly enough. A substantial percentage of the deaths that occur, come about after rather than during the storm.

Activity 2:

To study the effects of cyclones on people’s lives

[lo 2.1, 2.3]

• How can tropical cyclones cause people’s death?

4. Preventative measures: risk management and risk reduction

Even though a great deal of scientific knowledge exists regarding tropical cyclones, there is actually fairly little that can be done to prevent the damage these storms cause.

Still, there are a few things that can be done to reduce the damage to a certain extent:

Early warning systems involving satellite images, radar and weather station data can be used to predict the approach of a tropical cyclone;

Cloud seeding, a process which spreads out the energy of the cyclone and reduces the wind speed, is quite successful;

Limiting the damage it causes. This is probably the best way to handle a storm. Typical precautionary steps include the following:

• Shutters, windows and doors are nailed shut.
• Property is tied down, and all loose objects are packed away or tied to heavy furniture and trees so that they cannot be blown away. Flying objects usually cause great damage and can even cause people to be killed.
• Sandbags are piled up in places where a flood is expected, to halt most of the impact of the flood.
• People and property are evacuated from the area.

Activity 3:

To plan to aid people in a disaster area

[lo 2.3]

1. Imagine that you are the leader of an emergency team that is sent by the Red Cross to a tropical cyclone disaster area. Devise a plan to help the affected people. What would be the first measures to take? How much time would your rescue operation take?
2. Which precautionary measures can be taken to minimise the effect of tropical cyclones? Study the cyclone-warning pamphlet on p. 23 that is issued by the American Weather Bureau to assist you.