圖書典藏及影音數位平台

海堤前方水域以及河口水域之水文條件極為複雜，卻也是本署防汛期間溢淹預警與防治的重點區域。為能落實溢淹預警與防治的工作，常須借助數值模式進行水理演算以及溢淹之預測。然而不論是河口或是海堤前方水域的數值水理模式演算，都需要準確的地形資料作為依據，為有效落實海岸侵蝕防治工作，海岸相關權責單位過去曾透入大量的人物力出海進行海岸地形水深之現場量測工作。非接觸式觀測技術在岸邊即可進行，可大幅降低海上進行量測作業的成本與風險，且研發成果能提供後端數值水理模式演算所需之地形資料，藉以作為準確溢淹預警的依據。

The bathymetry in front of the seawall and inside the area of estuary is a key to evaluate the risk of flooding in these areas. Although the in-situ measurement using the acoustical technologies must be the most reliable way to obtain the coastal bathymetry, the risk and cost of this way should be considerable as well. Marine X-band radar, which is typically used to detect the coastline and obstacles on the sea surface, is currently one of the most widely used tools for ocean remote sensing. Marine X-band radar should be a potential equipment to observe the bathymetry nearshore. The aim of this program is to study the innovated technology of bathymetry estimation using the X-band radar images. To achieve this aim, this program will be finished within two years. In this year, some works have been achieved. For the development of bathymetry observation based on the X-band radar, a new algorithm based on the Teager energy operator is proposed. Field experiments in the coastal areas of Hualien and Tainan. Data analysis have been implemented as well. After a series of tests and experiments, we confirm that the X-band radar is capable of monitoring for nearshore bathymetry. Through this program, the bathymetry observation based on the remote sensing technology is improved. It is efficiency for Water Resources Agency to prevent the climate change impacts in the future. These recoded data are important for the safety of seawall and the warning of flooding disaster.