FY 1999

Coastal Meteorology

Overland, J.E., and C. Friehe

Chapter 2 in Coastal Ocean Prediction, C.N.K. Mooers (ed.), Coastal and Estuarine Studies, 56, American Geophysical Union, 7–29 (1999)

Coastal weather phenomena are the result of land/water contrasts in heating, orography and surface friction in response to large-scale weather systems. Unlike the open ocean where atmospheric dynamics are governed primarily by a geostrophic balance, in the coastal zone the influence of inertia is the same order of magnitude as rotation. Scale analysis suggests that the seaward influence of the coast is given by a Rossby radius of deformation of order 50–100 km. Alongshore winds can exhibit ageostrophic accelerations in response to an alongshore synoptic or locally induced pressure gradient. Coastal phenomena include damming of onshore flow, propagating trapped disturbances, lee side low pressure troughs such as the Catalina eddy, the sea breeze, and coastal fronts.