近年全球暖化現象日益嚴重,格陵蘭等極區融冰所造成之海平面上升將對全球人類帶來嚴重威脅。因冰層質量之改變與冰河移動速度高度相關,故可藉由監測格陵蘭冰層(Greenland Ice Sheet,GrIS)上冰河之移動推估全球暖化對其造成之影響。衛星影像因具有連續且快速獲得大範圍地表資訊之能力,且可結合各影像處理技術獲得地表變形量,故已廣泛應用於廣域冰河之監測。然不同影像與技術均有其優勢與限制,故本研究將使用合成孔徑雷達(Synthetic Aperture Radar,SAR)與光學影像,並結合合成孔徑雷達差分干涉(Differential Interferometric SAR,D-InSAR)、多重合成孔徑雷達干涉(Multi-aperture Interferometric SAR,MAI)與偏移偵測法(Pixel-offset,PO)技術獲得冰河表面於不同方向之位移向量,再整合各向量透過三維變動量解構法(3D decomposition)求解表面於三維方向之變形量。據此執行數值冰層動力模型(Numerical Ice Sheet Model,ISM),並結合模擬之冰底基岩渠道網絡、數化之冰面冰隙與冰面湖及氣象觀測資料後,參佐冰河變動理論,進一步了解格陵蘭Russell冰河之變動行為與機制。 / Global warming has been a worldwide issue and significantly increasing icecap melting rate over polar area. Consequently the sea level rises continuously and poses a fundamental threat to whole human beings. Since the mass loss of Greenland ice sheet (GrIS) is highly correlated to the velocity of glacier movement, this study aims to monitor the impact of global warming by tracking glacier terminus displacement over GrIS using remote sensing techniques. As there are multiple spaceborne images of various characteristics and also multiple techniques with different functions, we proposed a monitoring strategy using Synthetic Aperture Radar (SAR) and optical images, with Differential Interferometric SAR (D-InSAR), Multi-aperture Interferometric SAR (MAI) and Pixel-offset (PO) techniques to estimate glacier movement vectors. The vectors were then merged using 3D decomposition method to derive 3D deformation. Based on the resultant 3D deformation, the Numerical Ice Sheet Model (ISM) is conducted and then integrates with modeled subglacial drainage channel network and glaciological theories, the melting dynamics and mechanism of Russell glacier can be further understood.
Identifer | oai:union.ndltd.org:CHENGCHI/G0104257001 |
Creators | 蔡亞倫, Tsai, Ya Lun |
Publisher | 國立政治大學 |
Source Sets | National Chengchi University Libraries |
Language | 中文 |
Detected Language | English |
Type | text |
Rights | Copyright © nccu library on behalf of the copyright holders |
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