*5.2. Seasonal Wind Patterns and Long-Shore Currents*

Sti ff winds a ffecting the Gulf of California on an annual basis from November to May [5,7] are capable of generating large-scale wave trains that build in size and travel south over a wide fetch of open water. When sea swells cross into shallow water on approach to a north-facing shoreline, larger waves and surf may be generated that contribute to the abrasion of rocky shores. This action adds finer sediments to local beaches, often enriched by the abrasion of mollusk shells (see above). Such wave activity commonly occurs under clear skies in full sunshine that cannot otherwise be construed as stormy weather. Based on personal boating experience (MEJ), south-directed sea swells with an amplitude of 2 m and wavelength of approximately 10 m are not unusual along the coast near the study site during a wind event lasting several days. In the case of Ensenada Almeja, the waves originating from this source will impact the adjoining, north-facing rocky headland. Some amount of erosion can be expected against the exposed bedrock. However, this particular energy source does not account for the strikingly asymmetrical configuration of the Ensenada Almeja CBB. As apparent from aerial surveillance (Figure 3), the amount of boulder debris eroded from the east side of the headland is insignificant compared to the partial-ring CBB accumulated on the west side. Long-shore currents generated by the seasonal north winds in the region are insu fficient to account for the geomorphology of the Almeja CBB.
