7th International Conference on Southern Hemisphere Meteorology and Oceanography

Monday, 24 March 2003: 11:30 AM
Air-sea interaction in Wellington Harbour: the effects of wind forcing on turbulent mixing and stratification
Craig L Stevens, NIWA, Wellington, New Zealand; and M. J. Smith, B. Ward, C. J. Lemckert, and J. A. McGregor
At high wind speeds wave-breaking significantly influences turbulent transport in the upper few meters of the ocean, and therefore has a major influence on the exchange of heat, momentum, and mass between the atmosphere and ocean. Here we present results from air-sea interaction experiments in Wellington Harbour, New Zealand. This highly variable environment enables examination of the effects of changes in wind speed as well as the influence of stratification and surface cooling. The observations include temperature data from a SCAMP temperature gradient microstructure profiler, a VECTOR acoustic velocimeter, the cycling autonomous profiler SkinDeEP, and an S-band microwave radar used to quantify the white-capping percentage. Despite conditions where wind speeds exceeded 15 ms$^{-1}$, temperature structure persisted and was stratified in an ensemble-mean sense. The experiments highlight the persistent nature of stratification despite wave-breaking, and the role of air-sea thermal stability.

Supplementary URL: