Case Study For Global Hazards Flashcards
Consequences of the Boscastle Flood
1)58 properties, 4 businesses, roads and bridges were destroyed or damaged.
2) The flood was so sudden that people couldn’t evacuate or move belongings to safer places.
3) About 50 cars were washed out into sea. This caused some environmental pollution.
4) After the floods, the number of tourists dropped significantly. The village is a popular tourist destination and 90% of the local economy relies on tourism.
5)One person was seriously injured. Some residents suffered mental health problems after the flood due to stress relating to the floods and insurance claims.
Responses to the Boscastle flood
1)Emergency services quickly responded to save people in Boscastle.
Around 100 people had to be airlifted to safety by seven helicopters.
2)
Residents and tourists that were flooded out of their accommodation were looked after in local accommodation and the village hall.
3) Homes, businesses and roads were eventually rebuilt.
4) The bridge was rebuilt with a higher arch, so that debris is less likely to dam the river.
5) A £10 million new flood defence scheme was opened in 2008, which included widening and deepening the river to improve its flow.
Causes of the Bostcastle flood
1)75 mm of rain (the amount that would normally fall in a month fell in just two hours. A low pressure system brought warm, moist air from the Atlantic Ocean. This air mass cooled as it rose above the land, causing thunderstorms with intense rainfall.
2)Lots of rain over the previous weeks meant that the ground was wetter than normal, and could not absorb the water.
3) The old bridge in the village had a low arch over a very narrow river channel. The flooding was made worse because trees and vehicles in the flood water became trapped under the bridge, forming a dam.
Causes of the Australian Drought
-Australia has a naturally low rainfall due to global atmospheric circulation
The 30° S high pressure belt passes through Australia, causing low precipitation
-El Niño trade winds reverse so less warm water in water so little precipitation
Scientists think that climate change may be increasing global temperatures and changing rainfall patterns. So climate change may have contributed to the Millennium Drought:
• Temperatures in Australia were higher than normal during this period, resulting in more water evaporating than normal.
Weather fronts that normally bring rain to south-east Australia moved further south, away from Australia, causing annual rainfall totals to be lower.
Consequences of the Millennium Drought in Australia
1) Water levels in lakes and rivers (particularly the Murray and Darling) fell, so water supplies ran low.
2) The largest impacts were on farming:
• Crop yields fell, and crops that rely on irrigation (watering) were particularly badly affected, e.g. rice production fell to just 2% of pre-drought totals. This increased food prices.
• Livestock died — the number of sheep in Australia fell by around 8 million during 2002-2003.
3)Farmers’ incomes fell, and over 100 000 people employed in farming lost their jobs.
The drought caused vegetation loss and soil erosion and rivers and lakes suffered from outbreaks of toxic algae.
4)Dust storms caused by the drought affected inland Australia and some coastal cities.
5)The drought conditions were perfect for wildfires. Over 30 000 km houses burnt, animals habitats destroyed people died
Responses to the Millennium Drought in Australia
1)Water conservation measures were introduced. E.g. the 3 million people who rely on the River Murray for their water supply had their allocation reduced.
2) Cities such as Sydney built desalination plants that can turn sea water into drinking water.
3)The Australian government provided more than 23 000 rural families and 1500 small businesses with income support to help them survive.
4)The government is also investing in improving drought forecasts so farmers can prepare better, improving irrigation schemes and developing drought-resistant crops.
