1. Surpluses in the hydrological cycle

2. Today we are learning this content:
5.5 (a and b)

3. Surface water flooding
Complete the key terms
Flooding the occurs when intense rainfall has insufficient time to infiltrate the soil, so flows overland
Flooding that occurs after the ground has become saturated from prolonged heavy rainfall
A flood with an exceptionally short lag time - often minutes or hours
A type of glacial outburst flood that occurs when the dam containing a glacial lake fails.
Groundwater flooding
Flash flooding
Jokulhlaup
Surface water flooding
Prepare for learning

5. A number of environments are more at risk
Low-lying parts of flood plains and river estuaries
Urbanised areas
Small basins
For each of these environments explain why they may be more at risk of flooding – use Hodder p30

6. What causes flooding? Physical factors!
What meteorological factors cause flooding?
Physical factors!
Present new information
Page 31 and top of p32
Hodder. Use the fig 2.12
too

7. Examiners key points
Its crucial to have case studies for each one

8. Flooding - examples Monsoon rain – Pakistan
Present new information
Monsoon rain – Pakistan
Recap on how monsoons happen:
The Effects:
For each of these examples, you need to read through the geo factsheet and highlight the key points. You need to formulate notes in your book which helps you to explain why the floods occurred in these places. Be sure where applicable that you make sense of the synoptic chart that is shown.
Prolonged rainfall - The UK
Print off case study sheets.
Snow melt- Bangladesh
Flash Floods:
french-flash-floods-wreak-havoc-in-southern-city-of-
montpellier
Snow Melt:

9. Human causes of flooding
Urbanisation
River management
Climate change
Human causes of flooding
Deforestation
Use page 33 of Hodder plus computer research
Change of land use

10. How can we understand flood risk?
Flood frequency
The size of the largest flood event for each year for a particular location is placed in rank order, with Rank 1 being the largest for all available records for any given location.
The following calculation is applied to calculate the time interval between floods of a similar size.
 T = n+1 M
 Where
T = recurrence interval
N = number of years of observation
M = rank order
The calculated recurrence level indicates the number of years within which a flood of this size might be expected.
Limitations: based on historic data which means similar floods may occur more/less frequently. Climate change would lead us to think events will be more frequent.
The floods of highest magnitude will have much longer return periods – While they have the highest impact they may be less likely to occur.
Flood return
Also known as the flood recurrence interval
Estimate of the likelihood of a flood of a certain size recurring.
A flood likely to happen once in ten years has a 10% chance of happening in any one year
However….
This cannot be used as a forecast as a flood may happen more than once in the same time interval or may not occur at all.

11. Between 1900 and 2010 the Emergency Events Database (EM-DAT) recorded over 3000 flood disasters worldwide.
Intense flooding can lead to over supplies of sediment and nutrients, with possible eutrophication and destruction of aquatic plants.
90% of all flood deaths and 50% of economic damage occurs in Asia (China, India, Bangladesh, Pakistan and Vietnam)
Floods can recharge groundwater systems, fill wetlands, increase connectivity between aquatic habitats, and move sediment and nutrients around the landscape.
Flood depth is linked to mortality. In many LICs many people have not learnt to swim . Worldwide children and old people are particularly vulnerable.
Intense flooding can lead to pollution from nitrates, chemicals and heavy metals, all of which degrade aquatic habitats.
In HDCs property values are severely impacted in flood prone areas. Issues also arise when coming to resell properties
Structural damage to properties in all countries in a major cause of tangible flood losses
Crops, livestock and agricultural infrastructure suffer major damage. Subsistence farmers lose a lot of food supply. In HDCs this can also cause escalating food prices
Destruction of bridges e.g. Cockermouth, Cumbria can make communication between parts of settlements difficult.
In NICs growth exceeds flood defence provision so infrastructural loses are high
Income from tourism is disrupted.
The degree of threat posed by a flood depends on the depth and velocity of the water. Water 0.5m deep can wash cars away and cause the foundations of buildings to collapse
Flooding can trigger breeding of species and encourage migration and dispersal.
Floods between 1900 and 2010 were responsible for 200,000 deaths and 3 billion being impacted in some way
In LDCs post-flood morbidity is likely due to water borne diseases and secondary flood hazards.
Colour code your version of the grid above to show whether the impacts are socio economic or environmental

12. Socio economic – Red Environmental - Blue
Between 1900 and 2010 the Emergency Events Database (EM-DAT) recorded over 3000 flood disasters worldwide.
Floods between 1900 and 2010 were responsible for 200,000 deaths and 3 billion being impacted in some way
90% of all flood deaths and 50% of economic damage occurs in Asia (China, India, Bangladesh, Pakistan and Vietnam)
The degree of threat posed by a flood depends on the depth and velocity of the water. Water 0.5m deep can wash cars away and cause the foundations of buildings to collapse
Flood depth is linked to mortality. In many LICs many people have not learnt to swim . Worldwide children and old people are particularly vulnerable.
In LDCs post-flood morbidity is likely due to water borne diseases and secondary flood hazards.
In HDCs property values are severely impacted in flood prone areas. Issues also arise when coming to resell properties
Structural damage to properties in all countries in a major cause of tangible flood losses
Crops, livestock and agricultural infrastructure suffer major damage. Subsistence farmers lose a lot of food supply. In HDCs this can also cause escalating food prices
Destruction of bridges e.g. Cockermouth, Cumbria can make communication between parts of settlements difficult.
In NICs growth exceeds flood defence provision so infrastructural loses are high
Income from tourism is disrupted.
Floods can recharge groundwater systems, fill wetlands, increase connectivity between aquatic habitats, and move sediment and nutrients around the landscape.
Flooding can trigger breeding of species and encourage migration and dispersal.
Intense flooding can lead to over supplies of sediment and nutrients, with possible eutrophication and destruction of aquatic plants.
Intense flooding can lead to pollution from nitrates, chemicals and heavy metals, all of which degrade aquatic habitats.
Socio economic – Red Environmental - Blue

13. The impact of flooding in England and Wales, summer 2007
Create a case study on the England and Wales folds in Summer 2007
You should include detail on the following:
Causes – Hydrological and human – Specific named examples should be used here
Impacts – Social, economic and environmental – long and short term (again a range of named examples should be used)
Relevant maps, images, graphs should also be incorporated and their relevance explained.

14. Exam question
Construct new meaning
With the help of figure 2, explain why the floods occurred in Pakistan in August 2010 (4 marks)
Print off case study sheets.

15. Exam question
Construct new meaning
With the help of figure 2, explain why the floods occurred in Pakistan in August 2010 (4 marks)
Print off case study sheets.

16. Exam question
Construct new meaning
Using examples, discuss the impact of flooding on people and the environment (15 marks)
Print off case study sheets.

17. Homework Task
Using newspaper articles and publications such as Geofile and Geo Factsheets, research two contrasting flood events (different causes, countries at different levels of development) and prepare a quadrant form diagram to compare the environmental, social and economic impacts both immediately after the event and then short term and long term.

18. Environmental impacts
Flood event:
Social Impacts
Economic impacts
Environmental impacts
Immediate
Short term
Long term

19. Environmental impacts
Flood event:
Social Impacts
Economic impacts
Environmental impacts
Immediate
Short term
Long term

20. Environmental impacts
Flood event:
Social Impacts
Economic impacts
Environmental impacts
Immediate
Short term
Long term