12867 x 4408 px | 108,9 x 37,3 cm | 42,9 x 14,7 inches | 300dpi
Date de la prise de vue:
août 2011
Lieu:
London, England
Informations supplémentaires:
The Thames Barrier is the world's second-largest movable flood barrier (after the Oosterscheldekering in the Netherlands) and is located downstream of central London. Its purpose is to prevent London from being flooded by exceptionally high tides and storm surges moving up from the sea. It needs to be raised (closed) only during high tide; at ebb tide it can be lowered to release the water that backs up behind it. Its northern bank is in Silvertown in the London Borough of Newham and its southern bank is in the New Charlton area of Charlton in the Royal Borough of Greenwich. The report of Sir Hermann Bondi into the North Sea flood of 1953 affecting parts of the Thames Estuary and parts of London was instrumental in the building of the barrier Geographical weather system London is vulnerable to flooding. A storm surge generated by low pressure in the Atlantic Ocean sometimes tracks eastwards past the north of Scotland and may then be driven into the shallow waters of the North Sea. The surge tide is funnelled down the North Sea which narrows towards the English Channel and the Thames Estuary. If the storm surge coincides with a spring tide, dangerously high water levels can occur in the Thames Estuary. This situation combined with downstream flows in the Thames provides the triggers for flood defence operations. [edit] Rising water levels The threat has increased over time due to the slow but continuous rise in high water level over the centuries (20 cm (8 inches) / 100 years) and the slow "tilting" of Britain (up in the north and west, and down in the south and east) caused by post-glacial rebound. [edit] Historical flooding Fourteen people died in the 1928 Thames flood, and after 307 people died in the UK in the North Sea Flood of 1953 the issue gained new prominence. Early proposals for a flood control system were stymied by the need for a large opening in the barrier to allow for vessels from London Docks to pass through.
