Increasing risk

Increasing risk

1. places at risk

   • Perthshire and North Ayrshire - river flooding, rainfall to increase by 30%
   • St Andrews - coastal flooding from rising sea levels. Low lying parts of Edinburgh will suffer as tides grow stronger
   • Bristol channel, Severn and Avon - risk from sea level rise and storm surges. River flooding on the Severn and Avon is more common. Sea level to rise by 80cm
   • Thames Valley - risk from tidal and river flooding. Thames to rise by an average of 50cm
   • Humber - Sea levels expected to be 28cm higher by 2050
   • Norfolk - sea level rise of up to 76cm causing coastal erosion and making the threat of tidal surges worse
   • Medway Estuary - risk from sea level rise and flooding. Sea level to rise by 53cm

2. why risks are increasing

   • climate change - rainfall levels and intensity seem to be increasing, causing more river flooding. Storm surges and rising sea levels threaten our coasts
   • population migration - as more houses are built on floodplains and in coastal areas the natural flooding that has always occurred turns into a hazard
   • how we use the land - urbanisation creates more impermeable surfaces and faster land drainage, all of which increase runoff rates and river discharge

3. building on floodplains

   • As there is an ever growing demand for housing the governments target of 3 million homes by 2020 may not be possible with out building on flood prone areas.
   • Floodplains have long been sites for settlement. They are particularly good to build on as the land is naturally flat ad is relatively cheap to build on. Riverside housing is also attractive to buyers
   • coastal lowlands have similar advantages to floodplains but with the added drivers of tourism and retirement. Population growth in some of these areas is a result of migration from other regions

4. why do people stay in areas of high risk

   • changing risks
     • it is difficult to predict when or where an event may occur or what the magnitude will be. Natural hazards vary in space as well as time because of changing human activities and changing physical factors, such as tectonic plate movements
     • the rise in sea levels means that low lying coastal areas that were once safe places to live are now more prone to storm surges and floods
     • deforestation leads to less water being intercepted by the trees this increases the frequency and magnitude if flood events
   • lack of alternatives
     • Often the world’s poorest, most vulnerable people are forced to live in unsafe locations such as hillsides or floodplains, or regions subject to drought, owing to shortage of land or lack of knowledge or better alternatives.
   • benefits versus costs
     • People may subconsciously weigh up the benefits versus the costs of living in high risk areas. The benefits of fertile farming land on the flanks of a volcano, for example, may outweigh the risk from eruptions.
   • risk perception
     • People tend to be optimistic about the risk of hazards occurring. They are comforted by statistics which show that the risk of death from hazard events is far lower than that from influenza or car accidents. They also believe that if a high magnitude event has occurred, they may be safe for the next few years, although this is not necessarily the case