Impact of Sea Level Variations on Hydrographic Survey around Taiwan

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基本資料

Project title

Code/計畫編號

MOST109-2222-E019-001

Translated Name/計畫中文名

海水面變化對臺灣水深測量之影響

Project Coordinator/計畫主持人

Wen-Hau Lan

Funding Organization/主管機關

National Science and Technology Council

Department/Unit

Department of Communications, Navigation and Control Engineering

Website

https://www.grb.gov.tw/search/planDetail?id=13338230

Year

2020

Start date/計畫起

01-01-2020

Expected Completion/計畫迄

31-05-2021

Bugetid/研究經費

710千元

ResearchField/研究領域

土木水利工程

Taiwan is an island country entirely surrounded by the ocean, which is influenced by the ocean very large. It is necessary to improve the safety of marine navigation. The electronic navigational chart system is a very important technology that provides significant safety benefits. Ocean depth is essential data for electronic charts. Tide correction is one of the main error sources in hydrographic surveys. The reason is that traditional tide correction only considers the tidal effects at nearby tide gauge stations, which ignores that ocean tides are non-uniform around Taiwan geographically and sea level anomaly includes seasonal effect, resulting in large errors in bathymetric surveys. In this research, we calculate two factors impacting the accuracy of hydrographic surveys—including ocean tides and seasonal sea level cycle—using tide gauge records, satellite altimeter data and ocean tide model around Taiwan, and simultaneously analyze the accuracy of the ocean tide model around Taiwan. In addition, sea level anomalies are strongly influenced by climate change in recent years. An understanding of seasonal sea level cycle and its spatial and temporal changes is importance because its temporal changes can affect the frequency and magnitude of coastal hazards. Therefore, we apply the Ensemble Empirical Mode Decomposition method to sea level data to assess the stability of the long-term seasonal sea level fluctuations with time. 臺灣為一四面環海的海島型國家，受到海洋影響甚鉅，因此提升海上航行安全是必須的。電子海圖系統是航海領域的重要技術，能大幅度提升船舶於海上航行之安全。海水深度為電子海圖中不可或缺的資料，其中潮汐修正為水深測量主要誤差來源之一，其原因為傳統潮汐修正僅考慮鄰近潮位站的潮汐變化，忽略臺灣各海域的潮汐變化並不相同以及海水面變化中包含季節性訊號，導致水深觀測可能含有較大誤差量。因此本研究利用潮位站、衛星測高以及海潮模型計算海潮與季節性等海水面變化對於水深測量之影響量，同時以潮位站與衛星測高資料評估臺灣周圍海域海潮模型之精度。另外，近年來海水面變化受到氣候變遷影響非常顯著，因此了解海水面季節性的時間與空間變化是非常重要的，其變化程度將影響沿海災害發生頻率與程度。因此本研究亦將利用總體經驗模態分解法分析海水面資料，計算長期海水面之季節性變動性。

Keyword(s)

海水面變化
水深測量
潮位站
衛星測高
Sea level change
Hydrographic survey
Tide gauge
Satellite altimetry

DSpace CRIS

Impact of Sea Level Variations on Hydrographic Survey around Taiwan

基本資料

Description