Evaluation of Sea Surface Temperature-Dependent Whitecap Coverage Parameterizations Using In Situ Data

This study aims to evaluate previous parameterizations of whitecap coverage ( W ) based on in-situ observational datasets. Ten-meter wind speed measurements over the sea surface ( U 10 ) have been the most traditional and effective method of estimating W. A secondary variable—sea surface temperature ( T w )—is considered for better parameterization of W . A non-monotonic relationship is found between the W and T w because all the coefficients and exponent in the W - U 10 power-law fit are T w -dependent. Therefore, replacing the fixed slope variable of the power-law fit with the positively or negatively T w -dependent function does not result in significant improvements. When the T w -dependent coefficients and exponent are embedded in the W parameterization, a better estimation of W is obtained. T w related parameter of wind-sea Reynolds number contains wavefield information, which is also related to T w , making wind-sea Reynolds number an optional parameter for estimating W . We suggest that further improvement of W ( U 10 , T w ) parameterization requires consideration of more wavefield information.