Regional Shoreline and Beach Changes in the Santa Barbara Sandshed

Beach widths and shoreline change along Santa Barbara and Ventura Counties, California were evaluated using a 70-year record of rectified historic air photos. Beach widths have oscillated throughout the study period as opposed to narrowing as predicted by sediment supply reductions. Shoreline change rates evaluated using linear regression and end point rate analyses show differences between the wet/dry shoreline and back beach reference features. Most of these differences occurred along armored backed shorelines where the natural erosion of the back beach was halted while the wet dry shoreline continued to erode. Beach responses to single El Niño events form a predictable pattern of beach reorientation. Similar patterns of shoreline reorientation can be seen in the long-term shoreline change analyses providing evidence that El Niños may play an important role in long-term coastal evolution.