Development of an Inverse Estimation Method of Sea Surface Drag Coefficients under Strong Wind Condition

Noriaki HASHIMOTO, Masaki YOKOTA, Koji KAWAGUCHI, Kentarou YOSHIMATSU, Hiroyasu KAWAI
2009 Journal of Japan Society of Civil Engineers Ser B2 (Coastal Engineering)  
The sea surface drag coefficient used in the energy transfer function is simply described as a linear function of wind speed extrapolated from weak wind to strong wind condition. Accordingly, the accuracy of estimated waves under strong wind conditions seems to be unreliable. To deduce appropriate drag coefficient in high speed winds, the data assimilation method is considered to be a powerful tool, and is applied to WAM. Then the validity of the new method was examined by numerical
more » ... merical experiments. As a result, it is confirmed that the drag coefficient deduced by the model is accurate when the observation data is enough. It is also confirmed that the accuracy of the deduced coefficient can be improved by adding a priori condition if the observation data is not enough.
doi:10.2208/kaigan.65.181 fatcat:kp66v6plqjdfxeej5r2ctcrpx4