007 - Hurricanes

Factual Question

What is a hurricane?
How do hurricanes form?

Debatable Question

Can living in a hurricane prone area ever be considered safe?

Key Terminology

  • Hurricane
  • Coriolis force
We will be using the words above today and by the end of the lesson you will understand what they mean. If you are still unsure of their definition then the useful link below will remind you of what the words mean.

Useful Link

Activity One - Watch - Why is Wind Important?

You have learnt in the previous lesson that the direction of the wind can impact how we live our lives. Wind can be both a positive and negative force of nature. As you watch the DVD ' How Earth Made Us - Wind' from the BBC, answer the following questions in full sentences on paper:
      1. How does the wind help humans?
      2. How has the wind harmed humans?
      3. What have humans done to harness the wind?
Or complete the chart below.

How Earth Made Us - Wind

Copy of How Earth Made Us - Wind




Activity Two - Organise

For this activity you will be exploring how hurricanes occur and why they are fascinating to explore. You may also have heard about the devastation that Hurricane Harvey has caused to the South of the USA and this activity will help to explain how that hurricane was formed.
  1. Collect an envelope of cards which contain a series of hurricanes statements. Your task is to sort out the hurricane statements in to points of interest and how a hurricane occurs. If you don't have the envelopes then you can just use the statements in the table below.
      • Draw a table in your book; it should have two columns and 5 rows.
      • Title the first column ‘How a hurricane occurs’ and the other ‘Diagram of Process. 
      • Find the statements which describe the formation of a hurricane and write them in order in your table. (Left hand side)
      • Once you have written how hurricanes occur you now need to draw pictures to illustrate.
    2.  Now in your book write down all the facts about hurricanes.


Hurricane Statements

Hurricanes gather heat and energy through contact with warm ocean waters.

Hurricanes only form over really warm ocean water of 80°F or warmer. The atmosphere (the air) must cool off very quickly the higher you go.

Each hurricane usually lasts for over a week, moving 10-20 miles per hour over the open ocean.

Hurricanes rotate in a counter-clockwise direction around an "eye." The centre of the storm or "eye" is the calmest part. It has only light winds and fair weather.

The wind must be blowing in the same direction and at the same speed to force air upward from the ocean surface.

When they come onto land, the heavy rain, strong winds and large waves can damage buildings, trees and cars. 

Evaporation from the seawater increases their power. 

A hurricane is a huge storm! It can be up to 600 miles across and have strong winds spiralling inward and upward at speeds of 75 to 200 mph. They are called tropical cyclones in Asia.

The Coriolis Force is needed to create the spin in the hurricane and it becomes too weak near the equator, so hurricanes can never form there. 

They often occur in areas that are between 5 and 15 degrees North and South of the Equator.

Hurricanes names are chosen from both boys and girls names and they go down the alphabet each season. If a hurricane does significant damage, its name is retired and replaced with another.

Winds flow outward above the storm allowing the air below to rise.

The Atlantic hurricane season is from June 1 to November 30, but most hurricanes occur during the Autumn months. The Eastern Pacific hurricane season is from May 15 to November 30.

One of the deadliest hurricanes was the Bhola Cyclone which hit Pakistan and killed between 300,000 and 500,000 people in 1970.

      


    

Activity Three - Classification

  • Before we look at how hurricanes can be classified watch the two youtube clips and mindmap the damage that is caused to humans, the environment and property.
  • Suggest why it might be important to classify the strength of hurricanes now you have seen what damage can be caused.

Tacloban Before and After

Typhoon Yolanda



  • Using the description box and website link below; describe the different categories of hurricanes using images. This could be done as a guide on A4 paper to advise people of the damage that may be caused by different category hurricanes.

Hurricane Damage

Category

Winds (MPH)

Pressure (Millibars)

 Pressure(Inches)

Storm Surge
(Feet)

Damage

1

74-95

<980

<28.94

4'-5'

Minimal

2

96-110

979-965

28.91-28.50

6'-8'

Moderate

3

111-130

964-945

28.47-27.91

9'-12'

Extensive

4

131-155

944-920

27.88-27.17

13'-18'

Extreme

5

>155

<920

<27.17

>18'

Catastrophic




 Useful Resource

National Hurricane Centre





Activity Task Four - Preparation

  • For almost every type of disaster that can happen in the world some sort of disaster plan of action has been written. What would you do to protect your house, pets and your family from the destruction of a hurricane?
  • Use the information image and youtube clip below to help you.
Taken From: http://ready.ga.gov/wp-content/uploads/2015/01/Hurricane-Preparation.jpg

Hurricane Preparation