Beach deflation and backshore dune formation following erosion under storm surge conditions: an example from Northwest England

Field observations following a major storm surge on 26 February 1990 on the Sefton Coast in Northwest England showed that the rate of aeolian sand transport and backshore dune construction varied significantly alongshore in response to variations in beach morphology and sand wetness. These variations, in turn, were determined by longshore variations in the character of marine sediment transport processes and the distribution of subsurface silt and peat formations which outcrop locally on the foreshore. The grain size of the beach sands was found to be very uniform and was not a factor influencing spatial variations in sand transport rate. Since the beach sediments consisted of well-sorted and very well-sorted fine sands, partly reworked from the dunes during the storm surge, deflation was not grain-size selective during the period of post-surge dune recovery.