Diurnal Sea Breeze-Driven Cross-Shore Exchange on the Inner Shelf in Central Monterey Bay
Abstract
Cross-shore exchange on the inner shelf has important impacts on the ecosystem, transporting heat, nutrients, pollutants and phytoplankton between the midshelf and surf zone. The effects of a strong (cross-shore wind stress, Tsx >0.05Pa) diurnal (7-25 hrs) sea breeze on cross-shore exchange at Marina, Monterey Bay, California is investigated using two years of continuous winds, waves, and ocean velocities. Surface wind stress has spectral peaks at 1, 2, and 3 cpd and the diurnal wind variability is greater than 50%. Similar spectral energetic peaks also occur with waves and currents. During sea breeze relaxation (-0.05Pa < Tsx < 0.05Pa), a background wave-driven inner-shelf undertow profile exists, which is equal and opposite to Lagrangian Stokes drift, resulting in a net zero Lagrangian transport at depth. In the presence of a sea breeze (Tsx >0.05Pa), a uniform offshore profile develops that is different from the background undertow profile allowing cross-shore Lagrangian transport to develop, when including Lagrangian Stokes drift. The seasonality of waves and winds modify the diurnal sea breeze impact. Therefore, material is hypothesized to incrementally move onshore near the surface and offshore near the sea bed only during sea breeze events.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2009
- Accession Number
- ADA496755
Entities
People
- John E. Hendrickson
Organizations
- Naval Postgraduate School