Sec 2 Geography Types of Floods

5.1 Types of Floods

1. Floods: What are floods? Source: http ://aecnews.net/related-bodies-meet-on-prevention-of-bangkok-floods/

2. What are Floods? Floods : How Can Cities Prepare For Floods? 2 ‘Floods are overflows of large amounts of water onto land that is normally dry.’ Source: https://popspoken.wordpress.com/2011/04/20/review-the-noose-season-4-episode-7-the-ninja-auntie /

3. Have anyone of you experienced the Orchard Road flooding in 2011/ flooding? Do you think Yew Tee will be flooded?

4. Why is it important to learn about floods?

5. Number of events Flood events in Singapore 1 Bukit Timah Canal overflowed on 19 November 2009 2 Orchard Road flooding 16 June 2010 3 Orchard Road flooding 23 December 2011 4 Western parts of Singapore 5 September 2013 Why is it important to learn about floods?

6. Describe the types of floods Coastal floods River floods Flash floods Lesson Objective

7. Coastal Floods Definition: Coastal floods occur in areas along the coast (especially low-lying coastal land, such as river mouths ) Floods: How Can Cities Prepare For Floods? 8

8. River floods Definition: River floods occur when water in the river rises and overflows its banks Floods: How Can Cities Prepare For Floods? 9 A cross-section of a river channel

9. River floods River floods occur on the floodplain , which consists of the river and the low-lying land on either side of it Levees: Raised banks on both sides of the river. Floods: How Can Cities Prepare For Floods? 10 A cross-section of a river channel

10. Flash floods Definition: A flash flood can be recognised by its quick rise in water level. It can take place suddenly and lasts for a short period of time Floods: How Can Cities Prepare For Floods? 11 Flash Flood in Pakistan, July 2010

11. Great Tohoku Earthquake and Tsunami that hit Japan in 2011 caused a coastal flood in Miyako City Mississippi River, USA 2011 Flash flood in Colorado , USA, September 2013 Video

12. Great Tohoku Earthquake and Tsunami 2011 Play video from the start to 1.08minutes.

13. 1. From the video, what is Japan experiencing? Earthquakes and Tsunami . 2 . What is the cause of the coastal flooding? Tsunami 3 . How do we know if it is a coastal flooding? The tsunami is approaching the coast . We can observe that the ships and boats are drawn away by the water. Questions from worksheet 5.1A

14. River flood: Play video from the start to 0.13minutes, then start at 0.39minutes to the end(2.26). The video shows an aerial view of the Mississippi river, the image was taken by Landsat 5 (satellite). Show the outline of the river (in dotted lines) State what is the cause of the river flood. Observed the contrast between the non-flooded areas and flooded areas. ( Pause at 0.59, 1.22, 2.01, 2.05, 2.19 ) Observed that the crops are being inundated. Mississippi River, USA 2011

15. 1. What causes river flooding? Heavy spring rains /heavy rainfall Snowmelt 2. How do we know if it is a river flood? The flood occurred along the Mississippi River . Water overflow out of the banks. Questions from worksheet 5.1A

16. Flash flood: Play video from the start to 1.58 minutes. Flash flood in Colorado , USA, September 2013

17. 1. What weather is Colorado facing? (Circle the answer) Extreme weather – Wet or Dry. ( Large or Small) amount of rain expected. 2 . What is the cause the flash floods? Extreme weather / Heavy rainfall 3 . How do we know if it is a flash flood? (0.30minutes) Spike in the river gauge, in less than ____ 15_ ____ minutes, __ 10 ___ feet of water slamming down. Questions from worksheet 5.1A

18. Other possible causes for floods

19. Coastal Floods Other possible causes: Intense storms such as tropical storms and tropical cyclones. Tropical cyclones are also known as typhoons and hurricanes. Storm Surges Floods: How Can Cities Prepare For Floods? 20

20. River floods Other possible causes: Dam failure Floods: How Can Cities Prepare For Floods? 21

21. Flash floods Other possible causes: Coastal and river floods Floods: How Can Cities Prepare For Floods? 22

22. Workbook Activity 5.1 Page 117 & 118 Describe the types of flood. Identify the flood type Give evidence Practice Time! Describe: means provide facts about the distinctive features of an item .

23. Recap