This is a response made to Jeremy Kuper, freelance journalist, whose article “London under water” appeared on the website of the Guardian Newspaper, dated 11 May, 2008.
- Please click on the title link, for the article to appear
IT’S not just London that is faced with the predicament of being flooded by a powerful tidal surge, or tsunami, that might, one day, hit these shore. Most of low lying England, particularly the Fens within East Anglia, could be wiped out if such a catastrophe was to occur. In recent times, the country has, of course, been witness to some heavy flooding. Rivers have overfilled and burst their banks, with fast flowing water stemming from rivers in Wales that feeds directly into the Thames. Within a few days, the emergency services were struggling to cope with the deluge of helpless people, stranded and waiting for assistance. Many people still face financial ruin, awaiting insurance settlements on their former homes.
The biggest issue facing Britain is expecting 19th. Century Sea defences to meet with the threats of a 21st. Century problem. Sea walls, for example, or riverbank enforcements are totally inadequate in meeting with the swell of water at high tide. We hear of government announcements of pledging more money and resources into the environment agency, but how is that being used? Should the government not be focusing upon strengthening and building-up of these defences, rather than hoping that such recent floods have been one-off events? Clearly, the Thames Barrier itself is too small in dealing with the menace and threat of global warming.
What lessons, if any, has the British government taken from the Boxing Day tsunami of 2004? Geographers and scientists worldwide indicated the need for an enhanced ‘early warning system’ that would give the emergency services and contingency planners extra time in alerting and moving people to higher ground.
Storm surges are huge elevations in sea level which strike unpredictably, can happen at any time but are generally likely to happen during the winter months. Those travelling down the North Sea pose a particular threat to the East Coast of the U.K. and Thames Estuary. The Met Office Storm Tide Forecasting Service records around twenty East Coast surge events a year.
Most of these storm surges arise around the Grand Banks, off the coast of Canada. The warm Gulf Stream meets the cold Labrador current in this region and areas of low atmospheric pressure (depressions) form.
Beneath a depression the sea is sucked up into a hump, small at first but stretching over a footprint of perhaps a thousand miles diameter. Winds associated with the depression drive the hump eastwards across the Atlantic, the dynamic effect magnifying the height of the hump as it travels.
Storm surges often pass unnoticed between Iceland and Scandinavia but occasionally one veers into the confined space of the North Sea. With north westerly winds blowing on its flank the hump is forced between the converging coastlines of England and continental Europe. This funneling effect further increases the height.
Occasionally a surge does not behave as predicted. This is a cause of real concern because it upsets forecasts and leaves low lying regions unprepared. An example is the East Coast surge of 19th to 21st February 1993. At Aberdeen the surge was already beginning to exceed the model. It continued to do so at Newcastle, Hull and Immingham. By Cromer in Norfolk it was almost double its forecast height and this pattern continued past Felixstowe in Essex. At the last moment the surge began to conform. When it reached Southend, the gateway to the Estuary, it was back to forecast levels. Still massive but a near miss, not a disaster.
Copyright © MarKat (Scotland) 2007-2008: all rights protected
Filed under: early warning system, east anglia, environment agency, flooding, global warming, london, london under water, sea defences, thames barrier, tidal surges
