全球暖化使極端氣候事件增加，近四十多年間，臺灣地區年降雨日數呈減少現象，年平均降雨強度呈增加現象。極端降雨事件的增加，將導致崩塌與土石流災害更加頻繁、土壤沖蝕速率加劇，使地表地貌變化速度加快，因此為獲取地表地貌長期的變化資訊，需要大範圍且長期連續獲取之資料來源。福衛二號為每日再訪衛星，自2004年5月發射以來，為台灣累積了十二年的觀測資料，利用其立體像對產製數值地形模型，可獲得大範圍且長期的地表地貌變化資訊。
福衛二號為獲得更多的地面資訊，較少以大視角進行拍攝，不易獲得常使用的基高比介於0.6 ~ 1之立體像對。立體像對產製之數值地形模型理論精度為：影像地面解析度 / 基高比x匹配精度。因此，若要以基高比小於0.6的立體像對獲得較高精度之數值地形模型，需要提高影像匹配精度。衛星拍攝時的視角越大，影像變形越嚴重，影像匹配的精度通常也較低，在地形起伏劇烈的山區尤為嚴重。SIFT影像匹配方法，具有影像尺度及旋轉下特徵不變的特性，在視角變化與光照角度變化的情況下能產生良好得匹配結果。
本研究使用福衛二號短基線距立體像對產製數值地形模型，以建立台灣長期之地表地貌變化，主要可分為三個部分：福衛二號影像幾何校正、以SIFT方法進行影像匹配、使用ENVI的DTM產製模組產製數值地形模型。研究區域為2009年莫拉克風災的強降雨引發大規模崩塌的小林村。本研究將分別產製崩塌災害前後小林村地區的數值地形模型，與現有之數值高程模型比較並評估精度，並以此估算小林村大規模崩塌的土方量。
本研究所產製之數值地形模型已能大致反映地形的變化趨勢，與現有之數值高程模型相比，災前RMSE為17.99公尺，災後RMSE為26.81公尺，估算之崩塌土方量約為3397.3萬立方公尺。

Global warming have contributed to the increase of extreme weather and climate events. Over the past 40 years, the annual rainfall days in Taiwan have decreased, and the annual average rainfall intensity has increased. The increase of extreme rainfall events will lead to more frequent landslides and debris flows, increased soil erosion rates, and accelerated changes in surface geomorphology. Therefore, in order to obtain long-term changes in surface geomorphology, large-scale and long-term continuous sources of information are needed.
FORMOSAT-2 is a daily revisited satellite. Since its launch in May 2004, it has accumulated 12 years of observations for Taiwan. Using its stereo image to produce digital terrain models (DTM), it can obtain a wide range of long-term surface geomorphology change information. For the sake of obtaining more ground information, FORMOSAT-2 is less likely to sense with a large viewing angle, and it is not easy to obtain a stereo pair with a B/H ratio of 0.6 to 1 that is often used.
This study uses FORMOSAT-2 narrow baseline stereo to produce a digital terrain model to establish long-term surface geomorphic changes in Taiwan. It can be divided into three parts: FORMOSAT-2 image geometric correction, SIFT method for image matching, and use ENVI DTM extraction module produces digital terrain models. The study area is Hsiaolin village, where large-scale landslide disaster caused by the heavy rainfall during Typhoon Morakot in 2009. This study will separately produce the digital terrain model of the Hsiaolin village area before and after the landslide, compare it with the existing digital elevation model and evaluate the accuracy, and estimate the large-scale landslide volume in Hsiaolin village.
The digital terrain model produced by this study can roughly reflect the trend of terrain. Compared with the existing digital elevation model, the RMSE before the disaster is 17.99 meters, the RMSE after the disaster is 26.81 meters, and the estimated volume of landslide is about 3397.3x10¬7 m3.

Alvioli, M., Melillo, M., Guzzetti, F., Rossi, M., Palazzi, E., von Hardenberg, J., Brunetti, M. T., and Peruccacci, S.: Implications of climate change on landslide hazard in Central Italy, Sci Total Environ, 630, 1528-1543, 2018.
Borgatti, L. and Soldati, M.: Landslides as a geomorphological proxy for climate change: A record from the Dolomites (northern Italy), Geomorphology, 120, 56-64, 2010.
Chen, L.-C., Teo, T.-A., and Liu, C.-L.: The geometrical comparisons of RSM and RFM for FORMOSAT-2 satellite images, Photogrammetric Engineering & Remote Sensing, 72, 573-579, 2006.
Crozier, M. J.: Deciphering the effect of climate change on landslide activity: A review, Geomorphology, 124, 260-267, 2010.
Dadson, S. J., Hovius, N., Chen, H., Dade, W. B., Hsieh, M.-L., Willett, S. D., Hu, J.-C., Horng, M.-J., Chen, M.-C., Stark, C. P., Lague, D., and Lin, J.-C.: Links between erosion, runoff variability and seismicity in the Taiwan orogen, Nature, 426, 648-651, 2003.
ENVI: DEM Extraction Module User’s Guide. 2006.
ERDAS: Leica photogrammetry suite project manager guide. 2005.
Gariano, S. L. and Guzzetti, F.: Landslides in a changing climate, Earth-Science Reviews, 162, 227-252, 2016.
IPCC: Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp., 2014.
IPCC: Summary for Policymakers. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S. K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA., 2013.
Joglekar, J. and Gedam, S. S.: Area based image matching methods—A survey, Int. J. Emerg. Technol. Adv. Eng, 2, 130-136, 2012.
Kao, S.-J., Huang, J., Lee, T., Liu, C., and Walling, D.: The changing rainfall–runoff dynamics and sediment response of small mountainous rivers in Taiwan under a warming climate, Sediment Problems and Sediment Management in Asian River Basins (IAHS Publ 349), 2011. 2011.
Li, Z., Zhu, C., and Gold, C.: Digital terrain modeling: principles and methodology, CRC press, 2004.
Liu, S. C., Fu, C., Shiu, C.-J., Chen, J.-P., and Wu, F.: Temperature dependence of global precipitation extremes, Geophysical Research Letters, 36, 2009.
Lowe, D. G.: Distinctive image features from scale-invariant keypoints, International journal of computer vision, 60, 91-110, 2004.
Lowe, D. G.: Object recognition from local scale-invariant features, 20-27 Sept. 1999 1999, 1150-1157 vol.1152.
Miller, C. L. and Laflamme, R. A.: The digital terrain model-theory and application., Photogrammetric Engineering and Remote Sensing., 24, 433-443, 1985.
Mitshuharu, T. and Seiich, H.: DEM accuracy derived from ASTER data, ACRS, Geoscience/DTM, 1996. 1996.
Morgan, G. L. K., Liu, J. G., and Yan, H.: Precise Subpixel Disparity Measurement From Very Narrow Baseline Stereo, IEEE Transactions on Geoscience and Remote Sensing, 48, 3424-3433, 2010.
Morgan, G. L. K., Liu, J. G., and Yan, H.: Sub-Pixel Stereo-Matching for DEM Generation from Narrow Baseline Stereo Imagery, 7-11 July 2008 2008, III - 1284-III - 1287.
Nearing, M.: Potential changes in rainfall erosivity in the US with climate change during the 21st century, Journal of Soil and Water Conservation, 56, 229-232, 2001.
Nearing, M., Pruski, F., and O'neal, M.: Expected climate change impacts on soil erosion rates: a review, Journal of soil and water conservation, 59, 43-50, 2004.
NGIS基本地形圖資料庫分組網站: https://bmap.nlsc.gov.tw/index.php/2018-01-18-03-58-49/2018-01-18-07-53-12, 2019. 2019.
Rianna, G., Zollo, A., Tommasi, P., Paciucci, M., Comegna, L., and Mercogliano, P.: Evaluation of the Effects of Climate Changes on Landslide Activity of Orvieto Clayey Slope, Procedia Earth and Planetary Science, 9, 54-63, 2014.
Sinha, U.: http://aishack.in/tutorials/sift-scale-invariant-feature-transform-scale-space/, 2010.
Smith, T. M. and Reynolds, R. W.: A Global Merged Land–Air–Sea Surface Temperature Reconstruction Based on Historical Observations (1880–1997), Journal of Climate, 18, 2021-2036, 2005.
Toutin, T.: Geometric processing of remote sensing images: models, algorithms and methods, International journal of remote sensing, 25, 1893-1924, 2004.
Wilson, J. P.: Digital terrain modeling, Geomorphology, 137, 107-121, 2012.
Wolf, P. R. and Dewitt, B. A.: Elements of photogrammetry: with applications in GIS, McGraw-Hill New York, 2000.
Yang, D., Kanae, S., Oki, T., Koike, T., and Musiake, K.: Global potential soil erosion with reference to land use and climate changes, Hydrological Processes, 17, 2913-2928, 2003.
尹孝元, 梁隆鑫, 陳錕山, and 黃珮琦: 衛星影像於國土變異監測之應用, 航測及遙測學刊, 15, 65-78, 2010.
王成機, 陳思仁, 管長青, 鄭宏達, 林耀宗, and 吳錫賢: 高精度及高解析度數值地型模型測製及公路工程應用, 中華技術, 75, 66-75, 2007.
江介倫: 氣候變遷對臺灣年降雨沖蝕指數潛在影響, 地理學報, doi: 10.6161/jgs.2013.68.01, 2013. 1-17, 2013.
李錫堤, 董家鈞, and 林銘郎: 小林村災變之地質背景探討. 地工技術, 2009.
周士傑 and 劉蒨蒨: 福衛二號立體取像與影像精度, 航測及遙測學刊, 19, 297-302, 2015.
林育樞, 何學承, and 蘇苗彬: 應用數值航空攝影測量於坡地災害土砂分布及變異量之推估, 中華水土保持學報, 44, 282-292, 2013.
林昭遠, 陳昱豪, and 林家榮: 集水區泥砂產量推估之研究, 水土保持學報, 38, 207-218, 2006.
林義乾: 以影像控制區塊進行福衛二號衛星影像定位, doi: 10.6342/ntu.2006.03125, 2006. 土木工程學研究所, 臺灣大學, 1-118 pp., 2006.
侯進雄, 費立沅, 邱禎龍, 陳宏仁, 謝有忠, 胡植慶, and 林慶偉: 空載光達數值地形產製與地質災害的應用, 航測及遙測學刊, 18, 93-108, 2014.
施虹如, 吳亭燁, 蘇元風, 劉哲欣, 李欣輯, 陳永明, and 張志新: 極端降雨事件下淺層崩塌潛勢衝擊評估分析, 工程環境會刊, doi: 10.6562/jee.2015.34.5, 2015. 77-95, 2015.
洪偉嘉, 黃大任, 黃金維, and 張磊: 時域相關點雷達干涉技術應用於雲林嚴重地層下陷區監測, 航測及遙測學刊, 19, 225-237, 2015.
范正成, 楊智翔, 張世駿, 黃效禹, and 郭嘉峻: 氣候變遷對高屏溪流域崩塌潛勢之影響評估, 中華水土保持學報, 44, 335-350, 2013.
國家太空中心: 福爾摩沙衛星二號計畫簡介, https://www.nspo.narl.org.tw/tw2015/projects/FORMOSAT-2/program-description.html.
國家災害防救科技中心: 臺灣氣候變遷災害衝擊風險評估報告, 行政法人國家災害防救科技中心, 新北市, 2016.
張中白, 王志添, 王皓正, and 陳錕山: 應用雷達差分干涉法監測都會型地表變形：以中壢工業區爲例, 航測及遙測學刊, 9, 9-14, 2004.
張智安 and 陳良健: 有理函數模式於高解析衛星影像幾何改正之應用, 航測及遙測學刊, 12, 257-272, 2007.
莊宗達: 福衛二號立體像對產製數值地表模型之適用性分析, 碩士, 地理學系, 國立臺灣師範大學, 台北市, 79 pp., 2009.
陳世師: 福爾摩沙衛星二號立體像對產生數值地形模型之精度研究, 碩士, 地理環境資源學研究所, 國立臺灣大學, 台北市, 79 pp., 2006.
陳志豪, 林慶偉, 陳勉銘, 張維恕, and 劉守恆: 多時序衛星影像在崩塌研究之應用－以高雄縣荖濃溪為例, 中華防災學刊, 3, 25-38, 2011.
陳俊愷, 張國楨, and 莊宗達: 福衛二號立體像對產製數值地表模型精度分析 環境與世界 2010. 55, 2010.
陳柏澧: 福爾摩沙二號衛星數值地表模型與正射影像產品之產製與精度評估, 碩士, 衛星資訊暨地球環境研究所, 國立成功大學, 台南市, 129 pp., 2009.
陳樹群 and 吳俊鋐: 高雄縣小林村獻肚山巨型深層崩塌引致之地形變遷特性, 中華水土保持學報 2009. 359, 2009.
單新建, 柳稼航, and 馬超: 2001年昆侖山口西8.1級地震同震形變場特徵的初步分析, 地震學報, 26, 474-480, 2004.
童慶斌, 國家災害防救科技中心, 李培芬, 林幸助, 李明旭, 盧虎生, 蘇慧貞, 張靜貞, 詹士樑, 許泰文, and 李河清等: 臺灣氣候變遷科學報告2017－衝擊與調適面向, 2017.
黃郁棠, 張奇, 吳究, and 蔡長興: 以統計同質分布散射體干涉雷達技術偵測地表變形, 航測及遙測學刊, 19, 239-251, 2015.
楊佳祥, 蔡展榮, and 蘇柏宗: 改良型PS-InSAR測量法求定臺灣中部地區的地層下陷量, 航測及遙測學刊, 19, 171-187, 2015.
經濟部中央地質調查所: 臺灣之活動斷層分布與地表變形觀測, 2013.
葉家承, 張智昌, and 徐百輝: 福爾摩沙衛星影響於災害應變之應用－以汶川地震為例, 國研科技, doi: 10.29659/narlq.200807.0013, 2008. 56-61, 2008.
壽克堅, 吳秋靜, and 許惠瑛: 以SPOT衛星影像探討1999集集地震後之崩塌行為, 航測及遙測學刊, 15, 17-28, 2010.
劉哲欣, 吳亭燁, 陳聯光, 林聖琪, 林又青, 陳樹群, and 周憲德: 臺灣地區重大岩體滑動案例之土方量分析, 中華水土保持學報, 42, 150-159, 2011.
蔡展榮 and 陳鴻緒: 運用衛星雷達干涉測量法在臺灣地區求定數值高程模型之初步實驗成果和實務探討, 航測及遙測學刊, 7, 15-34, 2002.
賴栗葦 and 姜善鑫: 台灣地區之降雨變遷研究, 中華水土保持學報, 34, 161-170, 2003.
顧承宇, 陳建忠, 張怡文, 許世孟, 陳耐錦, and 溫惠鈺: 氣候變遷下極端降雨引致廣域坡地災害評估技術之研究, 中華水土保持學報, 43, 75-84, 2012.