Large-Scale Dynamics of California Coastal Jet

The low-level jet that occurs along the California coast during the summer months has had considerable study over the years. As shown in previous studies, the coastal jet plays an important role in coastal ocean processes as well as coastal climates. The jet is established by larger scale flow patterns and interacts with the coastal topography to produce along coast variations on smaller scales. As noted in previous studies, the primary dynamics governing the jet are due to thermal wind balance that occurs due to the slope of the marine boundary layer inversion toward the coast. This model of jet dynamics implies a distinct transverse circulation that should occur, similar to what is observed with the four quadrant jet model aloft. In this study, the Climate Forecast System Reanalysis data are used to examine the structure and evolution of the larger scale coastal jet and the associated transverse secondary circulation. The secondary circulation and its interaction with the marine boundary layer inversion structure is examined to relate these larger scale processes to the smaller scale coastal interactions that lead to accelerated flow around points and capes.