Variability in monthly occurrence frequency of internal waves in the East Vietnam Sea

In this study, a long-term time series of satellite observations (2005-2009) was used to investigate the occurrence frequency of internal waves in the East Vietnam Sea for different months. Satellite images in January, April, July and October of the period of 2005- 2009 were gathered with 30-meter resolution. Secondly, from the enhanced images, the traces of internal waves were digitized. Finally, the composite and occurrence frequency maps are built to analyze the variability of internal waves. It was noted that internal wavefronts mostly appear along the contour of 200 m depth. The occurrence frequency of internal waves reached its maximum values in July and April while values in January and October were insignificant.