Exceptionally high sea levels in the Solent

The hourly meteorological effect or surge component of sea level at two ports in the Solent has been derived from a comparison of-observed sea levels and predicted tidal heights generated by a specially developed computer program.Meteorological conditions antecedent to English Channel surges m propagating from the west have been Identified and empirical equations based on meteorological parameters have been developed for real time forecasting of surge heights at Portsmouth.Evidence relating to non-linear surge-tide interaction in the Solent has been examined and it has been shown that there is no definite tendency for surges to occur during any particular part of the tidal cycle. Various probability distributions have been fitted to annual maximum sea level series at three Solent locations using both graphical and objective methods. The variability to be expected from random samples from an extreme value distribution has been shown.The exact distribution of extremes theorem has been applied to high water data to provide a method which is considered to be of particular relevance to short tidal records. The effect of long term astronomical cycles on annual high water statistics has been studied using serial correlation. Evidence for cyclic variation has been found which has particularly important implications in the context of the annual probability of exceptionally high sea levels. This secular variation has been quantified using a joint (tide surge) probability method.