臺灣本島與離島潮位分析及深度基準探討

Abstract

參考基準面的建立，對當地或全國性的建設發展相當重要，精確的潮汐計算、分析為最直接的建立物理基準面，如平均海水面、約最低低潮或平均大潮低潮等，而潮汐的影響因子主要可分為有週期可循的天文因子與複雜多變的氣象因子。本研究採用調和分析法(T_Tide與UTide)保留影響潮位的天文因子，分析臺灣本島與離島地區共計十處潮位站(基隆33號碼頭、馬祖南竿、基隆長潭里、金門料羅灣、金門水頭、澎湖馬公、綠島、小琉球、蘭嶼和東沙島)觀測值，以數學統計方式與調和分析法分析當地潮汐特性與建立深度基準，並加以探討兩個不同調和分析法(T_Tide與UTide)的適用性與最低潮位面的建立，接著為探討深度基準與高程基準兩基準面上的垂直銜接問題，再分別與三個潮汐模型(TPXO 8-atlas、nao99b和DTU 10)比較探討三者模型對臺灣本島及離島的精度，此外假定直接觀測值減去分潮重組後的重組潮位值之殘差為氣象因子影響潮汐的影響量，以東沙島與基隆長潭里兩站三種不同潮位計(音波式、壓力式與雷達式)分別與潮位站所測得之氣象因子(水溫、氣壓)做回歸分析探討氣象因子與潮位之相關性。

The establishment of a physical datum is important for construction and development in coastal area or country. Tidal calculation, analysis and prediction are nesserssery while defining the datum. Tide affecting factors can be divided into many categories, periodic astronomical factors, complex meteorological factors, etc. This thesis adopts T_Tide (Pawlowicz, 2002) and UTide (Codiga, 2011) harmonic analysis methods. Experiement data received from ten tide stations which located in Keelung, Matzu, Kinmen, Penghu, Lüdao, Liuqiu, Lanyu and Dongsha. Tidal characteristics and depth datum are obtained from analysis using mathematical statistical method and harmonic analysis method. The applicability of two different harmonic analysis methods (T_Tide and UTide) and the vertical connection problem between depth datum and height datum are discussed. The comparison betwwen harmonic analysis result and three tidal models (TPXO 8-atlas, nao99b and DTU 10) show the accuracy of three models on Taiwan island. In addition, the thesis assume that observed tide minus the predicted tide of harmonic analysis is affected factors by meteorology. By defining the value of factor, the correlation between meteorological factors and tide can be calculated by regression analysis.