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Published byBailey Dalton Modified over 11 years ago
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Pick a Number to Reveal the Picture! 1111 2222 3333 4444 5555 Continue..
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InfoBack Insert image of Cadair Idris or similar steeply sloped landform
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Back Info GRANITE ROCK CHALK ROCK V Insert image of Chalk Rock Insert image of Granite Rock
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Back Info Insert image of woodland Insert image of heather moorland V
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Back Info Insert OS map that shows area with many streams Insert OS map that shows area with one river and few or no streams V
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Back Info Insert image of cumulonimbus cloud(s) Insert image of nimbostratus cloud(s) V
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STEEP SLOPES A drainage basin with steep slopes will result in any precipitation rapidly entering the river channel A drainage basin with steep slopes will result in any precipitation rapidly entering the river channel This will result in the peak flow (discharge) of the river being high and responsive in that it will reach peak discharge quickly and then fall away quickly once the rainfall event has ended This will result in the peak flow (discharge) of the river being high and responsive in that it will reach peak discharge quickly and then fall away quickly once the rainfall event has ended Back to Picture Back to Picture Board The steep slopes found on (e.g. Cadair Idris) results in a rapid transfer of water into the Nant Cadair stream Insert image of Cadair Idris or similar steeply sloped landform
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GEOLOGY The chalk (above) is permeable and as a result water is absorbed by the rock rather than allowing it to flow overland into the river channel Back to Picture BoardBack to Picture The granite (below) is impermeable and as a result drainage basins with rocks of this type will promote rapid runoff and could lead to flooding Insert image of Chalk Rock Insert image of Granite Rock
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Vegetation Vegetation can influence river flooding Vegetation can influence river flooding If a drainage basin has woodland like in the top picture, then more of the rainfall will be intercepted and subsequently lost due to evavoptranspiration If a drainage basin has woodland like in the top picture, then more of the rainfall will be intercepted and subsequently lost due to evavoptranspiration If little vegetation is present, more water will enter the river and promote a higher peak discharge If little vegetation is present, more water will enter the river and promote a higher peak discharge Back to Picture Board Back to Picture Insert image of woodland Insert image of heather moorland
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Some areas have a high number of streams draining the land, whereas other have very few. Some areas have a high number of streams draining the land, whereas other have very few. These differences in drainage density will result in differences in the speed in which water is transferred and therefore the potential flood risk These differences in drainage density will result in differences in the speed in which water is transferred and therefore the potential flood risk Back to Picture BoardBack to Picture The map of (e.g. Snowdonia) above has many streams and a high drainage density (& steeper slopes) The map of (e.g. Snowdonia) above has many streams and a high drainage density (& steeper slopes) The (e.g. River Meon) is the only river on the bottom map- it has a low drainage density The (e.g. River Meon) is the only river on the bottom map- it has a low drainage density Drainage Density Insert OS map that shows area with many streams Insert OS map that shows area with one river and few or no streams
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Cloud types and rainfall Back to Picture Board Back to Picture The cumulonimbus cloud at the top will produce intense torrential rain which has the potential to produce serious flooding The cumulonimbus cloud at the top will produce intense torrential rain which has the potential to produce serious flooding The Nimbostratus clouds on the right are normally associated with light drizzle The Nimbostratus clouds on the right are normally associated with light drizzle Insert image of cumulonimbus cloud(s) Insert image of nimbostratus cloud(s)
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Insert image of dense urban environment
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Urbanisation – Human Influence on flooding On the previous slide, there was a picture of an urban landscape. What influence could this have on flooding? On the previous slide, there was a picture of an urban landscape. What influence could this have on flooding? –Rapid transfer of water through the drainage and sewer systems –The concrete surfaces do not allow water to absorb into the ground But so what? Should we care? But so what? Should we care?
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Flooding: Should I be bothered?! Flooding has always been a problem Flooding has always been a problem for many places and recent high profile flooding events has raised our awareness. Do you remember News footage ofBoscastle in 2004 or perhaps Bangladesh in the same year? Boscastle flood footage Boscastle flood footageBoscastle flood footage More recently, British settlements have suffered from flooding and people have been left homeless whilst their homes have been allowed to dry out and be repaired More recently, British settlements have suffered from flooding and people have been left homeless whilst their homes have been allowed to dry out and be repaired This has meant that people have had to start paying higher prices for their house insurance, but how is this price calculated? This has meant that people have had to start paying higher prices for their house insurance, but how is this price calculated? Flood maps have been created by the Environment Agency and anyone can now see if they live in a flood risk zone Flood maps have been created by the Environment Agency and anyone can now see if they live in a flood risk zone Insert image showing effects of flooding e.g. Boscastle
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Are you at risk of being flooded? Tasks to complete Are you at risk? Are you at risk? Lets have a look at the school first by using the website http://www.environment-agency.gov.uk/subjects/flood/ and by typing in the school postcode Lets have a look at the school first by using the website http://www.environment-agency.gov.uk/subjects/flood/ and by typing in the school postcode http://www.environment-agency.gov.uk/subjects/flood/ Now have a look for yourself and find your own house. Paste your map into a word document and label where your house is and annotate with information on what the flood risk is (your house should be in the middle of the map generated) Now have a look for yourself and find your own house. Paste your map into a word document and label where your house is and annotate with information on what the flood risk is (your house should be in the middle of the map generated)
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The House Price Mystery On the following slide you will see four pictures of houses and we are going to work out the prices of them On the following slide you will see four pictures of houses and we are going to work out the prices of them Before we do this, decide which would be your favourite house and why? Before we do this, decide which would be your favourite house and why?
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£320,000 LOWER! £235,000 LOWER! £99,000! LOWER! £160,000 What are the prices of these houses? PO20 2HW 4 bed detached PL35 0HA (4 bed attractive location) PO4 9PS (2 bed terrace in city location) CA1 2DD (3 bedroom terraced- refurbished twice in the last 5 years) Higher or Lower? Insert images of houses of a variety of styles. NB: Houses shown do not have to correspond to the postcodes, the idea is rather just to give a visual stimulus...
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Environment Agency Flood Risk Maps Did you get them correct? Did you get them correct? However, some key questions? However, some key questions? –Which of the house prices surprised you? –Why has the final house been refurbished twice in the last 5 years? –Why is the attractive harbour side house cheaper than the 4 bedroom house found in a normal village? Can we use the flood risk maps to help solve this mystery? Can we use the flood risk maps to help solve this mystery? Use the weblink http://www.environment-agency.gov.uk/subjects/flood http://www.environment-agency.gov.uk/subjects/flood 1.Type the postcodes in for each of the four houses ( and their location will be exactly in the middle of the flood map 1.Type the postcodes in for each of the four houses (PO20 2HW, PL35 0HA, PO4 9PS & CA1 2DD) and their location will be exactly in the middle of the flood map 2.Paste the maps into a word document and suggest reasons for the differences in house price 3.For two of the houses, you might want to find out further information about flood events that have occurred recently- these could form the basis of a detailed case study
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Final thought provoking quote or image...?
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