The CFB represents the best available information on extreme sea levels within the UK. The methods used in the extreme value analysis are internationally pioneering and are best on the best available tide gauge data. To maintain this high standard, regular updates are required to reflect the most recent improvements in sea level science and newly available gauge information.
Even if there are no significant tidal flood events in the eight year update period, the results are expected to change if they are re-analysed. Changes are primarily due to differences in data, improvements to the statistical methods and understanding of spatial variation between tide gauges.
Changes in levels may be problematic to some users and decisions makers. To make these changes manageable, an eight year period of stability is considered practical for most purposes.