A hindcast wave model was built using the SWAN model to estimate wave fields in front of the Ida beach. To verify its accuracy, estimated hindcast results were compared with NOWPHAS wave data. From numerical results, it was found that the hindcast results were in good agreement in terms of the significant wave height. Although the mean wave period and direction had lower statistical quality than the significant wave height, their tendency was estimated reasonably well. Using hindcasted wave data, the characteristics of wave fields at the Ida beach and their relationship with Owase's buoy data were analyzed. The significant wave height at Ida was smaller than that at Owase. However, the significant wave height with 2 to 4 m in the east direction was similar between Ida and Owase. Finally, the relationship between wave fields and beach profile change under high wave conditions was analyzed using the hindcasted wave data and DEM data. From these results, it was shown that the hindcasted wave data at the Ida beach can be used to assess the characteristics of beach profile change more appropriately than Owase's buoy data.
Typhoon and storm surge are considered the biggest hazards that threaten coastal communities in Vietnam. The possibility of a large typhoon taking place in Southern Vietnam is considerably smaller than in the northern and central parts of the country. However, this does not necessarily mean that Southern Vietnam is less vulnerable against typhoons. In this paper the authors tried to analyze typhoon track data during the last six decades to analyze how frequently typhoons made landfall on southern coast, particularly focusing on the Mekong Delta. The analysis reveals that the chance of typhoons making landfall is not negligible, although the frequency is substantially lower than that in Northern or Central Vietnam. A questionnaire survey was also carried out to investigate disaster awareness amongst local inhabitants in the Mekong Delta. To do this, the authors visited many small coastal towns and the regional capital, Can Tho city, whose population is well over 1.2 million. The events of the worst storm in recent times, severe tropical storm Linda in late October 1997, which claimed more than 3,000 lives and caused severe damage in the delta and the remote islands, were also investigated by conducting interviews with local people who directly experienced the typhoon. The key objective of this paper is thus to understand the awareness and concern about typhoons and storm surges in the delta. The results show that the local population tend to have a high degree of awareness about the dangers posed by those events, contrary to the authors' original hypothesis. However, it is also noticeable that it is necessary to improve preparedness against coastal disasters in Vietnam, especially in term of the education of the younger generation, and the elaboration of a mitigation plan.