Upper Ocean Response to a Hurricane

Abstract The upper ocean response to a moving hurricane is studied using historical air-sea data and a three-dimensional numerical ocean model. Sea surface temperature (SST) response is emphasized. The model has a surface mixed-layer (ML) that entrains according to a velocity dependent parameterization, and two lower layers that simulate the response in the thermocline. The passage of Hurricane Eloise (1975) over buoy EB-10 is simulated in detail. SST decreased 2°C as Eloise passed directly over EB-10 at 8.5 m s−1. Model results indicate that entrainment caused 85% of the irreversible heat flux into the ML; air-sea heat exchange accounted for the remainder. The maximum SST response was predicted to be −3°C and to occur 60 km to the right of the hurricane track. This is consistent with the well-documented rightward bias in the SST response to rapidly moving hurricanes. The rightward bias occurs in the model solution because the hurricane wind-stress vector turns clockwise with time on the right side of the...