| Abstract: | Hurricane intensity and track are strongly affected by air-sea interactions. Classified as following swells,crossing swells, and opposing swells, the observed wave height was parameterized by using the 10-m wind speed collected on 5 buoys by the National Buoy Data Center during 13 hurricane events. The path information of these 13 hurricanes was obtained from the National Hurricane Center Best Track(NHC-BT). Results show that the wave height increases exponentially with the 10-m wind speed, and the wave height reaches the maximum value, 11.2 m(8.1 m),when 10-m wind speed is 40 m s-1 under the following and crossing(opposing) swell conditions. We find that the wave steepness(the ratio of wave height to wave length) is proportional to the-2/3 power of the wave age(the ratio of wave phase velocity to 10-m wind speed). The parameterizations of friction velocity and drag coefficient are tested using the buoy data collected in moderate to high wind under following, crossing and opposing swell conditions. A wave age dependent equation for drag coefficient is found more accurate and recommended for future usage in numerical models.Furthermore, these algorithms also suggest that wind-swell orientation needs to be considered to retrieve accurate surface drag under high winds and strong swells. |
