Weather and Climate GW3

Question 1

Describe the location of tropical cyclones.

Answer 1

1. 8 - 15 degrees north and south of the Equator.

2. Presence of water bodies with warm sea surface temeprature greater than 26.5 degree Celsius.

Question 2

Describe the characteristics of tropical cyclones.

Answer 2

1. Weather systems developing over tropical or subtropical waters.
2. Strong winds exceeding 64 knots or 119km/hr
3. Circulate clockwise in the southern hemisphere and counter clockwise in the northern hemisphere due to the coriolis effect, while spiralling inward to the cyclone centre or eye.
4. Low pressure with clear skies and calm winds at the eye.

Question 3

Describe the trajectory of a cyclone.

Answer 3

1. Start in warm waters
2. Move westward towards land.
3. Hit landfall
4. Eventually die out due as there is no more warm waters to fuel it.

Question 4

Name the 3 hazards associated with tropical cyclones.

Answer 4

1. Storm surges: Sudden rise of sea level in which water is piled up against the coastline beyond normal conditions at high tide.
2. Strong winds
3. Torrential rains: Cause flooding and landslides

Question 5

Explain the physical impacts of tropical cyclones.

Answer 5

1. Damage to infrastructure: Strong winds blow down buildings / Storm surge cause buildings to be destroyed -> homelessness; need to spend money to repair, thus less for other aspects.
2. Disruption of communication: Torrential rain causes flooding / Strong winds blow down electrical wires -> unable to communicate with others to seek help -> increased injury and death; loss of businesses affecting economy.

Question 6

Explain the economic impacts of tropical cyclones.

Answer 6

1. Cost of repair to infrastructure as they are destroyed by the storm surges and strong winds -> less money to build other aspects of the economy.
2. Loss of income due to ruined crops

Question 7

Explain the social impacts of tropical cyclones.

Answer 7

1. Disruption to water supply as water pipes burst / flooding cause water bodies to be contaminated -> people drink contaminated water -> water-borne diseases.
2. Spread of diseases as people drink contaminated water; stagnant water from the flooding, resulting in breeding of mosquitos and spread of mosquito-borne diseases.
3. Displacement of people from their homes.

Question 8

Discuss how emergency action / weather warnings and advisories can help to manage the impacts caused by tropical cyclones.

Answer 8

1. Allow people to evacuate to cyclone-proof shelters before the cyclone occurs -> reduce loss of lives.
2. Emergency action refers to assistance from governments and NGOs -> provide assistance to those caught in the cyclone affected -> reduce injuries and loss of lives.

Limitation: Limited by funds and availability of the shelters. Warnings might also be false and overtime, people may not heed them.

Question 9

Discuss how prediction and warning can help manage the impacts caused by tropical cyclones.

Answer 9

Predict when an cyclone occurs and the trajectory of a cyclone-> determine the area for landfall -> able to evacuate the people early -> reduce loss of lives.

Limitation: Climate records of past events only indicate the frequency and does not give accurate details about when future cyclones will occur.

Question 10

Discuss how coastal plain management helps manage the impacts caused by cyclones.

Answer 10

Governments discourage development at coastal areas by having developers pay higher tax for use at coastal areas which are vulnerable to cyclones -> reduce number of buildings being destroyed -> reduce destruction and loss of lives.

Limitation: Authorities need to be able to enforce the rules which requires time and manpower. Residents already living at the coastal areas might be reluctant to leave. The government will thus have to buy back the land which is costly.

Question 11

Discuss how floodplain management helps manage the impacts caused by cyclones.

Answer 11

Map out areas prone to flooding, and limit development at high risk areas -> reduce number of buildings being destroyed -> reduce destruction and loss of lives.

Limitation: Time and manpower needed to map out the flood prone areas. There might be limited land in the country thus it might be difficult to limit the developments.

Question 12

Discuss how reducing vulnerability of infrastructure can help reduce the impacts caused by cyclones.

Answer 12

1. Designing building that are resistant to wind and water damage -> less damage to infrastructure -> less destruction and loss of lives.
2. Regular inspection of river embankments and coastal dikes for breaches due to erosion -> reduce flooding and its impacts
3. Locating utility lines underground -> reduce disruption to communication -> able to seek help and the economy can continue.

Limitations: Costly, not all countries can afford.