Long-term variation of reanalyzed wind waves on the southern central coast, Vietnam

Abstract

    Recently, the southern central coast of Vietnam has suffered from severe coastal erosion. In order to cope with these problems, physical understanding of long-term wave characteristics is essentially important as basic engineering information. Accordingly, this study examines the long-term variation of reanalyzed wind waves in duration 1900-2010 at this area based on the ERA-20C reanalysis data set in order to clarify the long-term tendency as well as the seasonal characteristics of wave properties. On the overall, the seasonal variation in wave height, period and direction are shown to be significant. The monthly-mean wave heights and periods are correlated with 2nd order polynomials very well. The wave heights and periods in the dry season are respectively 3 and 1.5 times higher than that during rainy season. The dominant wave direction in the dry season is the NE, while it is the SW in rainy season. The potential wave energy in the dry season is about ten times higher than that during rainy season. In the two recent decades, wave energy have been considerably increased.