Hurricanes are measured using a scale called the Saffir-Simpson hurricane wind scale , a 1–5 rating based on a hurricane’s sustained wind speed. The scale estimates potential damage.
Category 1
2
3 (major) 4 (major) 5 (major)
Saffir-Simpson hurricane wind scale Sustained Winds Damage 119–153 km/h 154–177 km/h 178–208 km/h 209–251 km/h
252 km/h or higher Catastrophic damage will occur
Very dangerous winds; will produce some damage Extremely dangerous winds; will cause extensive damage Devastating damage will occur Catastrophic damage will occur
12 3 Being numerate
Draw the Saffir-Simpson scale as a bar chart in your copy. Label the x-axis ‘Categories 1–5’. Label the y-axis ‘Sustained Winds’. (You can choose either the lowest or highest recorded wind speeds.)
FUN FACT! The World Meteorological
Organization (WMO) is responsible
for naming hurricanes created in the North Atlantic Ocean. The WMO keeps six lists of 21 male and female names that are used in rotation, and recycled every six years.
Question Time
1. Explain what severe weather is. 2. What are tropical storms called in the following places? (a) The US (b) The Caribbean (c) Australia/Southeast Asia (d) Japan
3. Draw and label a diagram explaining how a hurricane forms. 215
FUN FACT! The diameter of a hurricane
is measured from one side to the other. Hurricanes can have a diameter of over 900 km!