Analyses of Sea Surface Temperature in the Pacific Ocean Using Empirical Orthogonal Function

• Main Authors: Hsu, Pao-Chen, 徐寶珍
• Other Authors: Ho, Chung-Ru
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/ye46ww

碩士 === 國立臺灣海洋大學 === 海洋環境資訊系 === 105 === Sea surface temperature (SST) is one of the best parameter for monitoring the changes of oceans because it would be affected by the interaction of circulation between oceans and the atmosphere. In this study, the SST data derived from National Oceanic and Atmospheric Administration (NOAA) satellites onboard the Advanced Very High Resolution Radiometer (AVHRR) are used to analyze the SST variations in the Pacific Ocean from 1981 to 216. The study areas are divided into the North Pacific Ocean (from equator to 60N in latitude and from 100E to 100W in longitude), the South Pacific Ocean (from equator to 60S in latitude and from 150E to 75W in longitude), and the whole Pacific Ocean (from 60S to 60N in latitude and from 100E to 100W in longitude) for discussion, respectively. The data are analyzed by using Empirical Orthogonal Function (EOF) and the results are then compared with the Oceanic Niño Index (ONI) and Pacific Decadal Oscillation (PDO). The first mode of EOF (EOF1) represents that the SST variation is caused by the El Niño phenomenon in all study areas. The phenomenon is more obvious in the South Pacific Ocean than that in the North Pacific Ocean. This mode also reflects the effect of PDO, but its correlation coefficient with principal component of EOF1 is less than that of ONI. The second mode of EOF (EOF2) reflects the SST increases possibly due to the global warming effect. The SST increases 0.0792C/year and 0.0744C/year in the South Pacific Ocean and the North Pacific Ocean, respectively. This implies that SST increase trend is higher in the South Pacific Ocean than in the North Pacific Ocean. The third mode of EOF (EOF3) reflects the distributions of three strong El Niño events in 1982-83, 1997-98, and 2015-16.