The drag coefficient is very important parameter that is used to calculate the air-sea momentum flux. Although the many estimation models of the drag coefficient have been proposed and discussed (conditions with extreme wind, wind wave, swell, etc.), the agreement has not reached yet. Comparison and evaluation of the model’s characteristics have been performed. However, assessment related climate change has not been done. For a global phenomenon associated with climate change due to change in wind speed, we focused on the El Nino and La Nina phenomenon. In this study, using the sea surface wind data, we investigated the influence of the air-sea momentum flux estimation for the year when the phenomenon occurred and did not occur. CCMP (Cross-Calibrated Multi-Platform) of NASA was used the sea surface wind data. The period is from January to December of El Nino phenomenon, La Nina phenomenon, and normal period. Studies of Charnock (1955) and Takagaki et al. (2012) (consider the extreme wind speed range) were used for the drag coefficient model. The annual mean global air-sea momentum flux showed that the maximum and minimum air-sea momentum flux value corresponded the normal period and the El Nino phenomenon, respectively. And the difference was as small as 7.4% and 7.0% in both models. In every month, it showed the maximum and minimum is the normal period and the El Nino phenomenon in both models, and the difference was as big as approximately 13.9% and 13.8%. We also investigated the difference of the air-sea momentum flux for each phenomena in 10 degree latitude bands and the proposed seven sea areas. As a results, the difference between the maximum and the minimum value corresponded to the La Nina and El Nino phenomenon showed approximately 18% from the north latitude 50° to the north latitude 60° in the high wind speed region. The wind speed in the North Atlntic showed that sea wind speed is a very large value for the El Nino and La Nina phenomenon. Therefore, in this region, the value of air-sea momentum flux corresponding to the El Nino and La Nina phenomenon was larger than that corresponding to the other phenomena.
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