1.Describe the scene (4 lines)2.Come up with 2 newspaper titles which could accompany this image One serious one not!

Creating a river flooding

CASE STUDY!LO: to discover WHY we create case studies

LO2: TO discover the key points you need to include in your case study

STARTER:In 10 lines or more fully explain the meaning of this graph, use examples in your answer

What is a CASE STUDY?• A case study is detailed piece of RESEARCH

work on a particular place, person or event.• It allows you to use real examples in your

exam which is expected in the final 3 questions of your Final exam

What goes into a RIVER flooding CASE STUDY?

Background

KEY FACTS

• Where in the world is the place? A couple of maps help!

• What countries and oceans are near it (if needed)• Population of the country if required • Capital City • Is it a MEDC or a LEDC• Are they affected by river flooding often? Why?• Are they affected by other natural hazards?

• Size of event (rainfall mm)• River names• Time of day (local time)• Death toll • Were some groups effected more than others?• Injuries• Economic cost to rebuild• Percentage of country killed/injured

Prediction & Preparation

Primary effects

Secondary effects

• What had been done to predict the event?• Was the event predictable, if not explain briefly why not• What was done to prepare/get ready for a flood?• What were the Government doing ? Flood protection?• What were the general population doing to prepare for a

flood event? Stockpiling sandbags, moving important documents to higher storage? Evacuation planning?

• What machines were used to monitor the situation?

What were the primary effects of the hazard? How many people did the primary hazard kill? Were the primary effects worse than people had

anticipated… why?

o What were the secondary effectso Were they predicted?o Were they worse than expected?o How does each secondary effect link back in to the original primary effect (could make a table)

PrimaryLed to Secondary

ManagementHow did they Manage the event

LONG TERM

• What was done?• How quickly did the government act?• What did they do to save lives?• Where were the injured put? Was it good enough?• Did the preparation help?• Did other countries have to come and help? What did

they do?• Did Aid agencies and charities come to help? What did

they do?• BUILD a TIMELINE OF MANAGEMENT

How much did the whole event cost, What were the effects on the Economy of the area? Was the country given money to rebuild from other

countries? Are they making any new plans on how to deal with the

disaster? E.g new dams, Will they be prepared for the next one? EVIDENCE!

LOCATION

Where is Boscastle?

A small town on the north coast of Cornwall. 30 kms north west of Plymouth.

Where is Boscastle?

Causes of the flood event

Remember to record them as Natural or Human

CAUSE 1: VERY HEAVY RAIN

Most of the rain fell in a five hour periodPeak intensities were in excess of 30mm/hr (0.5mm per minute)

A month’s rain fell in just 2 hours

Studies of extreme rainfall patterns have concluded that freak floods are more likely to occur in June, July and August than at any other month of the year.This is when atmospheric conditions, such as a warm ground surface, lead to the uplift of air masses which subsequently cool, producing cloud and rainfall formations.

At midday, on the 16th August 2004, heavy, thundery showers had developed across the South West, these were the remnants of Hurricane Alex which had crossed the Atlantic.

Bands of showers aligned themselves with winds that had converged along the coastal high ground around Boscastle, creating Cumulonimbus clouds 12192m (40,000ft) high and kept them stationary for many hours.

CAUSE 2: THE STEEP SIDED VALLEYSIt has been estimated that the Boscastle valley’s catchment area exceeds 23sq kms spanning inland to Bodmin Moor where many small rivers spring.

The steep sided valleys that converge down to the sea, known in the trade as “flashy catchments”, act as huge funnels and can produce true flash floods after a sudden cloudburst or prolonged heavy rainfall.

River ValencyRiver Jordan Bodmin Moor

CAUSE 3 – SLATEY IMPERMEABLE ROCKS with CLAY SOILS

The cause was the combination of

• intense convectional rain,

• local topography and

• the geology

= resulting in a flash flood no one could have predicted.

Cause 4 The site of Boscastle?

The harbour area is on low ground beside the sea

and on the flood plain of two rivers.

timeline of events

12.15 Rain gauge at nearby Lesnewth some 4km (2½ miles) up the valley, shows no rainfalland it is dry in Boscastle’s harbour area, yet there are torrential showers at Camelfordand at the top of Boscastle.

What happened?

15.30 River Valency begins to break its banks

Cars swept awayCars were swept out to sea, bridges were washed away and people clung to rooftops and trees for safety as torrential rain hit the area. Emergency workers mounted a huge operation to rescue residents and holidaymakers along a 32-km (20-mile) stretch of the north Cornwall coast around Boscastle.

16.00 a 3 metre wall of water runs through Boscastle car park at 40 mph.

17.00 Rescue Helicopters.

In an operation lasting from mid-afternoon until 2:30 AM, a fleet of seven helicopters rescued about 150 people clinging to trees and the roofs of buildings and cars. Amazingly, no major injuries or loss of life were reported. 55 residents were airlifted out by the Royal Air Force after the flooding, 35 BBC staff were flown in by other means.

Effectsthink about

short term (up to 1 week) and

long term

Businesses are grateful that tourists have returnedin droves after the grim scenes of 2004.

But there is a fear that many are there for the curiosity factor, and there has been hard work to try and ensure the visitors keep returning

Medium Term : Effect on tourismAbout 90% of Boscastle’s economy is dependent on tourism. After the flood, more than 20 accommodation providers were forced to shut, many of them individually owned bed and breakfasts. As about two thirds of the business is done during the six week school holiday, the effects were even more devastating with half the three weeks remaining.