can be substituted for machinery for much of the study, but periods of wave 
data may be closely correlated with beach changes at selected times in the 
study period. Offshore surveys to depths of 10 meters should be made twice 
each year to provide a total record of nearshore change. 
VI. SUMMARY 
A total of 2,158 profile surveys were taken at 32 profile line locations 
along Long Beach Island, New Jersey, from 26 September 1962 to 12 June 1973. 
These surveys included closely spaced measurements taken at nine locations within 
three adjacent groin cells for a period of nearly 1 year (August 1972 to June 
1973). The data were checked and verified by CERC personnel and subjected to a 
number of computer analysis techniques to obtain changes between surveys in above 
MSL unit volume, change in profile area, change in MSL shoreline intercept, profile 
envelopes, and linear regression trends. Additional processing was done using 
empirical eigenfunctions. The temporal and spatial changes of the profile lines 
were related to environmental process variables such as wind, waves, and storms. 
Seventy-seven storm events were identified over the study period from his- 
torical records. Beach changes which could be related to four individual storms 
were selected for detailed analysis. The most severe erosion of these four 
storms (between 23 October and 13 November 1968) caused a recession of the MSL 
shoreline of about 22 meters at profile line 4 where the volumetric change was 
nearly 10 cubic meters per meter. In spite of the generally severe erosion, 
several of the profile lines accreted during the interval emphasizing the 
extreme variability which was a general characteristic of the beach changes 
during the study. This means that longtime series studies are required to 
obtain statistical data on general beach trends. 
Detailed studies within three groin cells showed that at least three 
profile lines within a groin cell are necessary to determine the net erosion 
trend and transport direction. The change in beach volume or MSL intercept 
shown by a single profile line in a groin cell does not necessarily represent 
a characteristic change for that cell. Distance weighted volume calculations 
made from single profiles along a structured beach, therefore, are of question- 
able value. The closely spaced profiles and analysis of storm directions 
strongly support previous conclusions of a net southward littoral transport 
at least south of profile line 24. Evidence for a nodal area exists in that 
region. 
Regression analysis of the MSL intercept with time showed most profile 
lines accreting. The maximum and minimum accretion values were 2.3 and 0.24 
meter per year at profile lines 19 and 10, respectively. The maximum erosion 
occurred at profile line 21 which is receding at an annual rate of more than 5 
meters per year. The low R? value for most of the regression equations empha- 
sizes the variability of the individual profile lines. Profile line 21, however, 
has shown a persistent erosion trend over the course of the study. There is 
no discernible pattern to the regression values along the beaches. These rates 
must be treated with caution since they imply a degree of predictability to the 
long-term trend which does not exist. 
Though transport is toward the south along most of the beach, the closely 
spaced profile lines show shifts in the beach pattern that indicate reversals 
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