Main Causes And Effects Of The Boscastle Flood

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Boscastle Flood Using the information you have been given summarise the MAIN causes and effects of the Boscastle Flood On the 16 August 2004 Boscastle suffered extensive damage after flash floods caused by an exceptional amount of rainfall that fell over 8 hours in the afternoon. The floods were recorded as the ‘worst’ in local history. Boscastle is a small village in Cornwall, South West England. The village is home to 800 residents. These were flash floods that caused the village to be shocked and un-prepared. These floods were among the most extreme ever experienced in Britain, as literally the whole village had be torn apart and obliterated. The peak flow was about 140 m’s cubed. This was an unexpected flood, and the chances of this happening again are very slim, the chance of this happening in any one year is 1/400. The heavy rainfall started falling at midday on the 16th August, and it was recorded that 5 inches fell in 8 hours. The storm was a remnant of the Hurricane Alex, which had carried over the Atlantic. The rain was cause due to warm air picking up moisture - due to residual heat from the Atlantic sea - travelled towards the South West Cornish coast as prevailing winds. Upon contact with the topographically vertical coast, these winds experienced a strong up-drafting force thus causing internal moisture to reach the atmosphere, and consequently cool as a string of storm clouds. With convergence and coalescence, enhanced moisture levels resulted in heavy rainfall on the afternoon of 16 August 2004. 185 mm (7 inches) of rain fell over the high ground just inland of Boscastle. At the peak of the downpour, at about 15:40GMT, 24.1mm of rain (almost one inch) was recorded as falling in just 15 minutes at Lesnewth, 2.5 miles (4 km) up the valley from Boscastle. In Boscastle, 89 mm (3.5 inches) of rain was recorded in 60 minutes. Main Causes of the
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