ENGLISH

7卷/3期

7卷/3期

華藝線上圖書館

Pages:

1-17

論文名稱

岡山洪氾區遙感偵測分析

Title

Gangshan Flood Area Analysis Using Multi-temporal ERS SAR and SPOT Images

作者

呂黎光 , 吳仁明

Author

Li-Guang Leu , Ming-Ren Wu

中文摘要

洪水造成海岸地區或低漥地區的淹水,不僅造成居民財產的損失,同時,也威脅到居民生命的安全。洪氾區範圍常採用人工現場勘察界定,但洪氾期間洪水氾濫成災,現場調查工作艱鉅,現場作業人員安全堪慮,調查作業風險甚高,況且,大範圍洪氾區的現場調查作業曠日費時,人力與時間的投入所費不貲。於是,採用遙感偵測洪氾區域的方法,成了另一種快速、有效取得大範圍洪氾區域資訊的不錯選擇。 本研究遙感偵測洪氾區域乃透過影像資料分析,使用多時影像進行分析比較,可以偵測洪氾區域所在位置及範圍。1994 年八月道格颱風過境台灣,造成岡山地區嚴重淹水,蒐集當時衛星影像進行分析,結果與現場有關資料相互比對,顯示淹水位置與範圍十分吻合,證實遙感偵測洪氾可行性甚高,值得進一步研究應用。

Abstract

Flood threatens human being lives and assets in the coastal area and land submergence. Monitoring and controlling the extent of flood area, the field survey is laborious and enormously dangerous. Remote sensing technology takes the advantage of safety, economics, and synoptic view to obtain the information of flood water and land submergence quickly. The frequent non-availability of cloud-free multi-spectral data precludes optical remote sensing of flood area, especially during the period of maxi­mum water spread. By virtue of day and night observation and cloud penetration capability, the active microwave data from Synthetic Aperture Rader (SAR) offers a tremendous potential for mapping and monitoring the extent of land submergence. In this study, multi-temporal data included ERS SAR and SPOT MSS images were used to analyze and delineate flood water boundaries of Gangshan during the typhoon Doug pass through Taiwan on August, 1994. From the analysis result with microwave and optical data, satellite images can map flood area easy and manifestly and have a good agreement with field information. This study indicates that remote sensing mapping and analysis of flood area using multi-temporal satellite data is available. The advanced study need carry on and promote it to beneficial applications.

關鍵字

洪氾、遙測、道格颱風、影像融合、多時影像

Keywords

Flood, Remote Sensing, Typhoon Doug, Image Fusion, Multi-temporal Image

附件檔名

華芸線上圖書館

N / A

備註說明

200206-7-3-1-17

Pages:

19-27

論文名稱

海洋水色應用於石城定置網區水深之探測

Title

Applications of Ocean Color on Bathym etry Mapping For the Shye-Cherng Set Net

作者

蔡為鵬 , 陳俊德 , 林榮耀

Author

w. Tsai , C. Chen , J. Lin

中文摘要

本研究使用法國 SPOT 衛星影像遙感探測台灣東北角石城定置網海域之水深沿岸之海底地形,是使用海洋水色遙感探測在此區域推演水深的首次嘗試。為了驗證此一單反射水深推演(Single-reflectance water extraction Algorithm)的結果對照資料,本研究也使用傳統船測沿著固定航向航行使用聲納探測點的水深方法來比對。經過潮汐誤差修正,單反射水深推演(SRA)值略高於船測水深,平均誤差值為 0.5±1.2 米。此一結果顯示 SPOT 衛星具有較高的空間解析度,可提供台灣沿岸海域定置網漁場探堪之應用,亦可監測淺海水域的侵蝕與沈積或沿岸淺海生態環境保育之用。

Abstract

A SPOT satellite digital image was used for remote bathymetric mapping in the northeast coast of the Shye-Cherng set net. This work represents the first know attempt at water depth extraction for this region by using SPOT satellite data. To validate the ocean color single-reflectance water extraction algorithm results, this research also used a conventional shipboard surveying method. This method provides water depth information for a series of latitude and longitude points along zigzag transect. After tidal error correction, the computed water depth from the ocean color single-reflectance algorithm (SRA) agreed with the shipboard surveying, and the average error was 0.5±l.2 meter. The results suggest SPOT satellite has higher spatial resolution; meaning it could provide temporal and spatial information along Taiwan's coastal area for near-shore set net fishery. It also can be used for monitoring shallow water depth changes that are caused from erosion and deposition. This technique would be very useful for environmental studies of shallow water ecosystem

關鍵字

Keywords

Bathymetry, ocean color, and irradiance

附件檔名

華芸線上圖書館

N / A

備註說明

200206-7-3-19-27

Pages:

29-39

論文名稱

越南外海夏季冷水湧升變化之衛星觀測

Title

Summer Upwelling Variability Off Vietnam From Satellite Data

作者

郭南榮

Author

Nan-Jung Kuo

中文摘要

本文係利用 NOAA/AVHRR 海表溫影像來探討 1997 至 2000 四年間夏季發生於越南外海之冷水湧升現象,本文共選取 35 張雲量較少之海表溫 3 日合成影像,經由正交經驗函數(empirical orthogonal function,EOF )之分析結果,可看出第一主成份顯現海表溫在越南海域之沿岸分佈,並可看出冷水湧升強度之變化及冷水區移動之趨勢。第二主成分主要是顯示海表溫之離岸梯度變化。正交經驗函數分析亦顯示在 1997 年夏天之聖嬰期間,冷水湧升現象較明顯,但鄰近海域海表溫之水平分佈則較均勻,此與聖嬰期間西南季風較強,導致湧升範圍加大,平均海溫下降有關。至於 1998 年夏天之反聖嬰期間,則冷水湧升強度較弱,但與週遭海表溫之水平梯度則較明顯,此應與反聖嬰期間西南季風減弱有關。

Abstract

Satellite-sensed advanced very high resolution radiometer (AVHRR) sea surface temperature (SST) data over summers (1997-2000) were used to analyze the variability of the summer upwelling off the Vietnam coast. Empirical orthogonal function (EOF) analysis of the spatial variance for 35 nearly cloud-free composite images was performed. The first gradient EOF mode shows the alongshore structure of the cold upwelled water. The second mode reveals the variation of the cross-shore SST gradient. The EOF analysis also displays the impact of the 1997 El Niño and 1998 La Niña events on the summer upwelling off Vietnam coast. The stronger monsoon wind caused the stronger upwelling but the weaker horizontal SST gradient during 1997 El Niño summer. The opposite situation occurred during the 1998 La Niña summer.

關鍵字

南海、冷水湧升、海表溫、聖嬰現象、正交經驗函數

Keywords

South China Sea, Upwelling, Sea surface temperature, El Niño, Empirical orthogonal function

附件檔名

華芸線上圖書館

N / A

備註說明

200206-7-3-29-39

Pages:

41-58

論文名稱

全球及區域性海面溫度變化趨勢之探討

Title

A Study on Global and Regional Sea Surface Temperature Trends

作者

陳逸龍 , 何宗儒

Author

Yi-Lung Chen , Chung-Ru Ho

中文摘要

本文使用美國海洋暨大氣總署(National Oceanic and Atmospheric Administration,NOAA) 國家環境預報中心(National Centers for Environmental Prediction,NCEP)的海面溫度(Sea Surface Temperature,SST)資料,以線性迴歸分析其變化趨勢。1982 至 2001 年的全球海面溫度每十年上升約 0.11±0.03゜C 。在季節性的變化上,7~9 月的增溫現象比 12~2 月為強烈。全球的海面溫度變化趨勢分佈,除了少數幾個區域是呈現減溫現象外(如赤道太平洋及南太平洋高緯度區),絕大部份是呈現增溫的現象。另外,北半球及南半球的海面溫度變化趨勢分別每十年上升17±0.04゜C及 0.06±0.03゜C,而三大洋的增溫現象則以北大西洋最為強烈。

Abstract

Sea Surface Temperature (SST) data from 1982 to 2001 obtained from National Centers for Environ­mental Prediction (NCEP) at National Oceanic and Atmospheric Administration (NOAA) were used to calculate global and regional SST trends by linear regression. The global SST trend is 0.11 ¡Ó 0.03ȼJ/ decade during 1982-2001. In seasonal analysis, the warming trend is stronger in boreal summer than that in boreal winter. The SST trends in most areas are positive, except for some regions where are negative, e.g. equator Pacific and high latitude in the southern Pacific. The SST trends in the northern hemisphere and the southern hemisphere are 0.17 ¡Ó 0.04ȼJ/decade and 0.06 ¡Ó 0.03ȼJ/decade, respectively. The highest warming trend is in the northern Atlantic Ocean.

關鍵字

海面溫度、變化趨勢、衛星遙測、線性迴歸

Keywords

Sea Surface Temperature¡BTrends¡BRemote Sensing¡BLinear Regression

附件檔名

華芸線上圖書館

N / A

備註說明

200206-7-3-41-58

Pages:

59-74

論文名稱

利用小波理論分析衛星影像來推估海冰的飄移

Title

Wavelet Analysis of Satellite Images for Sea Ice Motion

作者

劉安國 , 趙雲鶴

Author

Antony K. Liu , Yunhe Zhao

中文摘要

本研究利用小波理論,分析 QuickSCAT衛星和DMSP SSM/I 衛星所收集之兩種不同性質 (QuickSCAT衛星是微波波段的背向散射,SSM/I衛星是微波波段的輻射)的影像資料,來推估每天海冰在南北極的飄移。由推算的結果發現,兩顆衛星雖然資料性質不同,但所推估之北極海冰在秋天、冬天及春天的飄移和海上浮標的觀測十分吻合,而且兩者是互補的。也就是說,若將三者的資料合併,便可更加完整地了解,北極地區海冰每日飄移的狀況。由南極地區的一個研究案例發現,海冰的飄移主要是風所推動的,而移動的方向大小也與周圍的風場?合。根據1999年12月所製作北極海冰的日飄移圖,發現海冰運行的模式每4到7天就有相當大的變化,而這些改變主要是受到北極氣壓的影響。

Abstract

QuikSCAT backscatter and DMSP SSM/I radiance data are used to derive sea ice motion for both the Arctic and Antarctic region using the wavelet analysis method. Sea ice motion of the Arctic for fall/winter/ spring time derived from NSCAT, QuikSCAT and SSM/I data agree well with ocean buoy observations. Both comparisons of result from QuikSCAT and SSM/I with buoys are compatible, and their ice tracking results complement each other. Sea-ice drift daily results from QuikSCAT, SSM/I and buoy data can be merged to generate composite sea ice motion maps for more complete coverage of sea ice motion. In the Antarctic, a case study shows that sea ice motion derived from NSCAT/QuikSCAT data is predominantly forced by and consistent with the surrounding wind field. Based on a series of daily Arctic sea-ice drift maps in December 1999, it is found that the major circulation patterns are changing and shifting significantly within every four to seven days and they are dominated by wind forcing.

關鍵字

小波轉換、QuickSCAT ASSM/I、 海冰運動、特徵追蹤

Keywords

Wavelet transform, QuikSCAT, SSM/I, sea ice motion, feature tracking

附件檔名

華芸線上圖書館

N / A

備註說明

200206-7-3-59-74

Pages:

75-85

論文名稱

利用實測生光資料於混濁河及河口反求懸浮顆粒及葉綠素濃度的個例研究

Title

Retrieval of Suspended Particulate Matter and Chlorophyll-a Concentration in a Highly Turbid Tropical River by in Situ Bio-Optical Data - A Case Study

作者

林依依 , 溫良碩 , 劉振榮 , 劉康克

Author

I-I Lin , Liang Saw Wen , G.R. Liu , K.K. Liu

中文摘要

本研究收集了淡水河區實測水面水色光譜及水質資料,並對已定義之數個遙測水色波段對淡水河懸浮顆粒及葉綠素濃度反求之準確性質做比較。 對懸浮顆料而言, 520nm及625nm為測試波段。由我們分析發現, 625nm波段較為適用。而目前在軌道上之水色衛星(如 SeaWiFS及 MODIS)。並未配備此一波段。只有2002年剛昇空之 ENVISAT-MERIS水色儀配有此一波段。 對葉綠素而言,以 443nm 和 490nm 波段比較,並發現在非常混濁(既懸浮顆粒濃度高,如淡水河)之情況下,490nm 波段比 430nm 波段對葉綠素濃度的反求有較佳的表現。

Abstract

In situ reflectance spectra and water quality data (Chlorophyll-a, Suspended Particulate Matter, temperature, and salinity) in different parts of a highly turbid tropical river were collected. Performance of typical remote sensing ocean colour bands for retrieval of SPM (Suspended Particulate Matter) and Chl-a (Chlorophyll-a) were examined. For suspended particulate matter retrieval, 520nm and 625nm bands were tested. It was found that 625nm band performs better than the 520nm band. As none of the current ocean colour satellites (e.g. MODIS, and SEAWIFS) are equipped with the 625nm bands, this result supports the importance of the 2 upcoming ocean colour satellites (ENVISAT-MERIS and ADEOS 2-GLI), both equipping with 625nm band, for SPM retrieval in a highly turbid condition. Chlorophyll-a retrieval was examined at the 2 typical Chlorophyll-a retrieval bands, 443nm, and 490nm. Almost no correlation (correlation coef­ficient ~ 0.00) were found between 443nm/555nm band ratio and Chl-a concentration. In contrary, though under highly turbid (SPM 4-25mg/l) environment, reasonably good correlation (0.83) is found between 490nm/555nm band ratio and Chl-a concentration (0-3.3ug/l). This result suggests that 490nm band is capable to reasonably retrieve Chl-a concentration up to around 3.3 ug/l even in a highly turbid tropical coastal river.

關鍵字

Keywords

附件檔名

華芸線上圖書館

N / A

備註說明

200206-7-3-75-85

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