碩士 / 國立海洋大學 / 漁業科學系碩士在職專班 / 91 / Abstract
Sea level uprising has been a key issue of global environment change and been highly concerned by general public of Taiwan where land source is limited. The phenomenon is not only a reaction to local or regional environment change but also a result of global climatic change.
In order to understand the linkage between fluctuations of Relative Sea Surface Height (SHH) at Keelung and Kaohsiung harbors and the regional as well as global climatic variation, we collected 50-year long SSH data of both harbors as dependent variable, various regional and global climatic factors as independent variables accordingly. The independent variables include monthly mean temperature and monthly mean sea level pressure at Keelung and Kaohsiung, monthly mean sea level pressure at Pen-gia-yu and Pen-hu islets, global sea surface temperature, Southern Oscillation Index (SOI), SST at Niño monitoring regions, North Hemisphere snow coverage, Pacific Decadal Oscillation (PDO) index and etc. We analyze these variables through different statistical analyses methods including graphical observation, simple correlation, cross-correlation, and two dimensional cross-correlation methods. This study takes into consideration all the factors regarding the SSH change at both Keelung and Kaohsiung and comes up with following conclusions:
1. The seasonal change and inter-annual change of the SSH at both harbors are very significant. Keelung has more seasonal change while Kaohsiung has more inter-annual change in terms of frequency and amplitude.
2. During 1950-2000, the SSH rising rate at Keelung is 1.52 mm/yr and the minimum value occurred in 1979. During 1950-2002, the SSH rising rate at Kaohsiung is 3.67 mm/yr and the minimum value occurred in 1963.
3. Accoring to the simple correlation and cross-correlation analyses,the local atmospheric pressure and temperature affect SSH directly without any time lag. However, the influences from the SST in Western Pacific region and SST in Niño monitoring regions, the PDO, and the SOI are less significant and effective with considerable time lags.
4. The SSH at both harbors has negatively correlated to the North Hemisphere snow coverage with 3-month time lag( lag=+3 ). However the influence of the climatic factors originated from tropical regions are apparently different. The SST of Niño monitoring regions links to the SSH of Kaohsiung more significantly than to those of Keelung. The time lag is estimated about 2 months, which coincides with the time taken by Kelvin Wave cross the Pacific during El Niño episode.
5. Results from two dimensional cross-correlation analyses indicate that the SSH at both harbors are positively correlated to relative high temperature regions covered by the South and North Pacific Gyres including the west Pacific warm pool and Indo-Pacific Ocean；Negative correlation are found in the relative low temperature and low sea level regions including regions north to the sub-tropical divergence zone, North American coast, and upwelling regions in South America. Therefore, the SSH fluctuation of the two harbors during the recent 50 years is actually a regional reaction to the SSH balancing in whole Pacific, and global climatic change probably manipulated the phenomenon behind.
| Identifer | oai:union.ndltd.org:TW/091NTOU1451029 |
| Date | January 2003 |
| Creators | Ying-Wei CHEN, 陳英偉 |
| Contributors | Hsueh-Jung Lu, 呂 學 榮 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 69 |
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