The San Fernando Convergence Zone

The vertical structure of a zone of converging winds in the San Fernando Valley is examined by using stadia pibal observations and a network of continuously recording surface wind stations. This zone of convergence, marking the location where two sea breezes of different points of origin along the southern California coast meet each other, apparently produces rising motions. The pattern of flow in the vertical plane normal to the convergence line is constructed by applying the continuity equation to the wind data. This pattern prescribes a redistribution of a ground-based layer of pollution on the Los Angeles side of the zone of convergence. This redistribution is compared with the actual distribution as observed from aircraft.