Thermal Structure and Airflow in a Model Simulation of an Occluded Marine Cyclone

Abstract

Abstract A very fine mesh model simulation of the Ocean Ranger storm of February 1982 is used to study the thermal structure and airflow in an intense marine cyclone. In particular, the study investigates the structures of the occluded front and the secluded pool of warm air in the simulated cyclone and examines the formation of these structures with the help of a large number of air trajectories. It was found that in the model simulation the largest thermal gradient occurred along the occluded front, not along the warm or cold fronts, and that the intense gradient was a product of strong warm and occludofrontogenesis in the inflowing air. The occluded front was embedded within air that was earlier located within the baroclinic zone ahead of the low center, not air that was in proximity to the historical warm and cold fronts. The warm air in the seclusion likewise originated in the baroclinic zone ahead of the low. The seclusion at low levels resulted from a tongue of slower moving, relatively warm air be...