Causes of beach lowering at Dunbar, Eastern Scotland, UK

This paper reviews the causes for falling beach levels at Dunbar East Beach. Beach widths and levels at East Beach have decreased since at least 1960, coinciding with the deterioration of a groyne and the installation of sewerage pipes. However, in addition to the work carried out at East Beach there have been changes in the wind climate. First, there has been a general increase in wind speeds from 1957 to 1996. Second, from 1987 to 1996, there has been an increase in the frequency of the mean Beaufort class from north-north-west to north-east directions, coupled with a decrease in the frequency of winds from the north-east to east-south-east. If these changes in wind have caused similar changes in the wave climate, then they could have produced an increased south-easterly (and possibly offshore) movement of material on East Beach, coupled with a decreased north-westerly movement. This would have produced a net loss of material from East Beach. The dilapidated state of the groyne may have facilitated this loss. A rise in relative sea level may also have contributed to increased sediment loss, especially in conjunction with the presence of a sea wall at the back of the beach. The relevance of these findings for other areas suffering from erosion is discussed.