||Investigating the spatiotemporal variation of crevasses, melt ponds and ice floes during the 2008 Ward Hunt Ice Shelf calving event- evidence from Formosat-2 remote sensing imagery
||Institute of Satellite Informatics and Earth Environment
high spatiotemporal resolution
冰架(ice shelf)不僅對氣候變相當敏感，其崩解(disintegration)也間接導致海平面上升與更嚴峻的暖化現象。一般而言，促使北極浮冰島(ice island)崩解(calve)的因素包含風的變化、海冰(sea ice)退卻、和冰架破裂(fracture)的擴張。雖然融池(melt pond)被視為冰架崩解的前兆，數量龐大的融池已經存在於部分加拿大極區冰架(Jeffries,2002)。但是這些融池和冰架崩解的關係至今仍未被完整的調查。本研究旨在利用高時空解析度影像為此提供初步的觀測和調查，以位於加拿大極區艾爾斯米爾島(Ellesmere Island)之沃德亨特冰架(Ward Hunt Ice Shelf)在2008 年三次的浮冰島崩解事件為例。此冰架自上個世紀初以來已經消失90%的面積，正說明了其對氣候變遷的敏感性。
國家太空中心(NSPO)於極區影像任務中在2007 年(2 幅)至2008 年(15 幅)夏季取得此冰架許多高時空解析度福爾摩沙二號衛星光學影像。融池、裂隙和浮冰等表面現象被萃取並用作變遷之分析。MODIS 影像也被用來分析第三次的崩解。
本研究有幾項發現。首先，融池的面積減少與裂隙長度的增加有高相關性。裂隙好發並擴張於融池以及溝豁(troughs) 間， 這顯示水力壓裂作用(hydro-fracturemechanism)對結構弱化的影響。此外，發展的趨勢意外的在七月十七日至二十八日間減少，顯示出有系統性的變化發生。其次，在2007 至2008 年夏季期間產生的溝豁發展成新的融池；部分並進一步成為裂隙(crevasse)以及崩解的冰緣(ice front)。這支持Holdsworth (1987) 有關此冰架丘豁交錯(hummocks and troughs)的獨特表面起伏特徵與海冰壓迫造成冰架彎曲的理論。這些現象不單為融水削弱冰架提出觀測上的證據，也符合水力壓裂作用在南極冰堡(ice berg)崩解中扮演的角色(Rist et al., 2002;Scambos et al., 2009a)。再者，此組影像也顯示海冰退卻與崩解的高相關性。最後，由入侵邊緣冰區的海冰流，延冰緣東向的海流，海冰在新的崩解灣(calving bay)的再次累積，以及冰架薄區域的分布等現象，可推測由迪斯雷利峽灣(Disraeli Fjord)經2002年發現的裂隙(crack)流出的季節性水流的存在，並證實其內淡水流失的現象(Jeffries etal., 1990; Mueller et al., 2003)。這海流可能也與差異化的冰架薄化(thinning, 特別是底層融化)以及2002 年和2008 年發現的這些裂隙的產生有關。
Ice shelves are vulnerable and sensitive to climate change. Their collapses indirectly lead to sea-level rising and further climate change. Typically speaking, causes for ice island calving in the Arctic include change of wind, sea ice retreat and fracture propagation. Although melt pond has been regarded as a precursor of the collapse of ice shelves, large numbers of melt ponds have been existed for at least a century in some of the ice shelves in the Canadian High Arctic (Jeffries, 2002). But the relationship between melt pond and ice island calving has not been well investigated yet due to lack of proper tool.
This research aims to provide a preliminary insight in the relationship between ice-island calving and variations of features on the surface of ice shelf and sea from high spatiotemporal imagery. The case study is the three calving events during 2008 melt season in Ward Hunt Ice Shelf (WHIS), Ellesmere, in the Canadian High Arctic. WHIS has lost 90% of its area since the beginning of the 20th century after its 3000+ years of existence, which has been regarded as very sensitive but vulnerable to climate change.
In 2007 (2 scenes) and 2008 (15 scenes), high-spatiotemporal optical images of Formosat-2 were acquired successfully in Polar Image Campaign (PIC) by National Space Organization (NSPO) from June to August. Surface features, such as melt pond, crevasse and sea ice, are extracted from these images for spatiotemporal analysis. MODIS imagery of WHIS is also employed to provide additional spatiotemporal information for the third calving event.
There are several findings. Firstly, the areal reduction of melt pond is highly correlated with the increase of crevasse length statistically. Furthermore, crevasse and rift tend to propagate through ponds and troughs, implying the effect of weakening due to hydro-fracture mechanism. However, the trend slowed down during July 17th and 28th, which reveals some systematical change in the drainage system. Secondly, new troughs are also observed during 2007-2008 winter, and then became melt ponds; some of these further propagated as rifts, and then resulted in calving, developed into new ice front along with the ex-fracture in some area at last, which supports Holdsworth’s propose (1987) related the formation of the unique land feature (with hummocks and troughs) to pack ice pressure, plate buckling and creep formation as a result. The above mentioned two phenomena altogether not only indicate that melt water does weaken the ice shelf, but also align with the theories of hydro-fracture mechanism on ice-berg calving in the Antarctica (Rist et al., 2002; Scambos et al., 2009a). Thirdly, this set of time-sequential imagery also shows that sea ice concentration over ice front has high correlation with calving events. Lastly, intrusive flow of pack ice to marginal ice zone, eastward flow along the ice front and formation of new fast-ice near to the east of the new calving bay (18 August 2008), combined with the distribution of thin areas in the map of thickness, altogether suggests that there is seasonal outflow from Disraeli Fiord through the central crack, found in 2002, which is consistent to previous studies about the existence of the flow and the drainage of the freshwater (Jeffries et al., 1990; Mueller et al., 2003). The bottom flows probably contribute to differential thinning (especially bottom melting) and formation of cracks both found in 2002 and 2008.
These findings imply that bottom flow is one of the potential mechanisms indirectly contributing to ice-island calving and ice-shelf disintegration, in addition to traditional factors, such as overall thinning, off-shore wind, sea ice retreat and wave propagation. This is to be simulated in calving model furthermore in addition to refinement and verification with more field data and analyses.
TABLE OF CONTENTS VI
LIST OF FIGURES IX
LIST OF TABLES XIII
CHAPTER 1 INTRODUCTION 1
1.1 POLAR REGIONS AND REMOTE SENSING 1
1.2 ICE SHELVES AND CLIMATE CHANGE 2
1.3 CALVING AND COLLAPSE OF ICE SHELVES 3
1.4 REQUIREMENTS FOR RESOLUTION 4
1.5 FORMOSAT-2 IMAGERY 5
1.6 OBJECTIVES 6
1.7 STRUCTURE 7
CHAPTER 2 REVIEW 8
2.1 FACTORS FOR ICE SHELF COLLAPSE 8
2.2 CALVING PROCESSES 10
2.2.1 Types of Calving 10
2.2.2 Some Mechanisms of Calving 12
2.2.3 Calving of Ice Island 14
2.2.4 Fracture Propagation 16
2.3 OPTICAL PROPERTIES OF MELT POND 19
2.4 TRACING SEA ICE MOTION 20
2.5 ESTIMATE THE THICKNESS OF ICE 21
2.6 SUMMARY: RATIONALE 22
CHAPTER 3 STUDY AREA – WARD HUNT ICE SHELF 23
3.1 GEOGRAPHY 23
3.2 ENVIRONMENTAL FACTORS 25
3.2.1 The Oceanic Factors 25
3.2.2 Decreasing Sea Ice Extent 26
3.2.3 Atmospheric Factors 27
3.3 INHERENT PROPERTIES 29
3.3.1 Thickness 29
3.3.2 Mass Balance 31
3.3.3 Topography 32
3.3.4 Formation of Hummocks and Troughs 33
3.3.5 Density Stratified Lake 35
3.4 SUMMARY, AND CLIMATE CHANGE 37
CHAPTER 4 DATA 40
4.1 SPECIFICATION AND CHARACTERISTICS OF FORMOSAT-2 40
4.2 APPLICATIONS ON POLAR REGIONS 41
4.2.1 Coverage over the Polar Regions 42
4.2.2 Temporal and Spatial Resolution 44
4.3 FORMOSAT-2 IMAGERY OF WHIS 47
4.3.1 Viewing Angle Group and Sun Elevation Angle 48
4.3.2 Pre-processing with F2AIPS 50
4.4 MULTI-TEMPORAL CO-REGISTRATION 52
4.4.1 No DEM nor Ortho-rectification 52
4.4.2 Work with Multi-temporal Co-registration Module of F2AIPS 54
4.4.3 Selection of Base Image 56
4.4.4 GCP Refinement 57
4.4.5 Assessment 58
4.5 SUPPLEMENTARY DATA AND PROCESSING 60
4.6 SUMMARY 61
CHAPTER 5 STRATEGIES AND METHODS 62
5.1 STRATEGIES 62
5.1.1 Multi-temporal Change Detection and Quality Control 63
5.1.2 Interpretation and Classification of Features 66
5.1.3 Detection to Hydro-fracture Processes 73
5.2 EXTRACTION OF MELT PONDS 75
5.2.1 Spectral Angle Mapper 75
5.2.2 A Glance to Pond Area Change 77
5.3 EXTRACTION OF CREVASSE 80
5.3.1 Challenges 80
5.3.2 Manual Digitization 81
5.4 EXTRACTION OF SEA ICE MOTION 83
5.5 APPROXIMATE THE THICKNESS OF WHIS 85
5.6 SUMMARY 87
CHAPTER 6 RESULT AND DISCUSSION 88
6.1 TEMPORAL CHANGES OF CREVASSE LENGTH AND POND AREA 88
6.1.1 Subset value of Ice Shelf Area and Pond Area 88
6.1.2 Density of Pond and Crevassse 91
6.1.3 Ratio of loss 93
6.1.4 Discussion 96
6.1.5 Summary 98
6.2 FROM TROUGH, MELT POND, CREVASSE AND RIFT FORMATION 103
6.2.1 Evidence 103
6.2.2 Discussion and Significance 104
6.2.3 Summary 106
6.3 ESTIMATED THICKNESS 108
6.3.1 Eestimating thickness from transects 108
6.3.2 Map of the Estimated Thickness 111
6.3.3 The Thin Area in the Southwest of WHI 111
6.3.4 The Thin Area in the East and Southeast of WHI 112
6.3.5 The Thin Area in the Northeastern NE subset 113
6.3.6 Summary 114
6.4 ON THE OCEANIC FACTORS -- SEA ICE MOTION AND TIDAL PREDICTION 115
6.4.1 First Glance at the Speed of Sea Ice Motion 115
6.4.2 Predicted Tidal Height and Cycle 117
6.5 A REVIEW OF THE THREE CALVING EVENTS IN 2008 117
6.5.1 Before the calving events (~July 8th) 117
6.5.2 The First Calving Event (between July 8th and July 17th) 118
6.5.3 The Second Calving Event between July 22nd and July 26th 121
6.5.4 Eastward Flow and Vortices 124
6.5.5 The third Calving Event (August 12th) 127
6.5.6 Rift formation to the south of Ward Hunt Island 128
6.6 SUMMARY 130
6.6.1 Change of CLD and PAD 130
6.6.2 Fracture on the calving front 130
6.6.3 Sea Ice Retreat 131
6.6.4 Flow and Current 131
6.6.5 Formation of Trough, Thickness and Crack 132
CHAPTER 7 CONCLUDING REMARKS 133
7.1 HYDRO-FRACTURE MECHANISM AND OCEANIC FACTORS 133
7.2 DIFFERENTIATE THINNING BY FLOW OR ALONG THE GROUNDING LINES 134
7.3 EXPECTED CONDITIONS OF DISINTEGRATION 135
7.4 FORMOSAT-2 IMAGERY OF ICE SHELF— CONSTRAINTS AND APPLICATIONS 137
CHAPTER 8 FUTURE WORK AND RECOMMENDATION 138
8.1 DATA COLLECTION 138
8.2 FIELD WORK 138
8.3 FOR SIMULATION 139
SCIENTIFIC GLOSSARY 149
APPENDIX 1 SPACEBORNE REMOTE SENSING PLATFORMS 151
APPENDIX 2 FORMOSAT-2 DATA GRANULES OF WHIS 156
APPENDIX 3 DYNAMIC CHANGE OF THE MARGINAL ICE ZONE IN ALERT 159
APPENDIX 4 EXAMPLES AND ASSESSMENT FOR MELT POND EXTRACTION 160
APPENDIX 5 STATISTICS OF CREVASSE LENGTH CHANGE AND MELT POND AREA CHANGE OF ICE SHELF AND MELT POND IN THE EASTERN WHIS 161
APPENDIX 6 TIDAL PREDICTION IN DISRAELI FIORD 164
APPENDIX 7 TEMPORAL CHANGES OF WHIS – ICE FRONT AND SEA ICE MOTION 166
APPENDIX 8 TEMPORAL VARIATION DURING WHIS CALVING EVENTS IN 2008 174
APPENDIX 9 BUCKLING MODELS 176
Alley, R.B., P.U. Clark, P. Huybrechts, and I. Joughin: "Ice-sheet and sea-level changes", Science, 310, 456-460, 2005.
Alley, R.B., H.J. Horgan, I. Joughin, K.M. Cuffey, T.K. Dupont, B.R. Parizek, S. Anandakrishnan, and J. Bassis: "A Simple Law for Ice-Shelf Calving", Science, 322, 1344-, 10.1126/science.1162543, 2008.
Antoniades, D., C. Crawley, M.S.V. Douglas, R. Pienitz, D. Andersen, P.T. Doran, I. Hawes, W. Pollard, and W.F. Vincent: "Abrupt environmental change in Canada's northernmost lake inferred from fossil diatom and pigment stratigraphy", Geophysical Research Letters, 34, L18708, 10.1029/2007gl030947, 2007.
Bamber, J.L., R.B. Alley, and I. Joughin: "Rapid response of modern day ice sheets to external forcing", Earth and Planetary Science Letters, 257, 1-13, 2007.
Bamber, J.L., and A.J. Payne: Mass balance of the cryosphere: observations and modelling of contemporary and future changes, Cambridge University Press, 2004.
Benn, D.I., and D.J.A. Evans: Glaciers and Glciation, John Wiley & Sons, New York, USA, 1997.
Benn, D.I., C.R. Warren, and R.H. Mottram: "Calving processes and the dynamics of calving glaciers", Earth-Science Reviews, 82, 143-179, 10.1016/j.earscirev.2007.02.002, 2007.
Bindschadler, R., and T. Scambos: "Satellite-image-derived velocity field of an Antarctic ice stream", Science, 252, 242-246, 1991.
Bottos, E.M., W.F. Vincent, C.W. Greer, and L.G. Whyte: "Prokaryotic diversity of arctic ice shelf microbial mats", Environmental Microbiology, 10, 950-966, 10.1111/j.1462-2920.2007.01516.x, 2008.
Bourke, R., and R. Garett: "Sea ice thickness distribution in the Arctic Ocean", Cold Regions Science and Technology, 13, 259-280, 1987.
Braun, C., D.R. Hardy, R.S. Bradley, and V. Sahanatien: "Surface mass balance of the Ward Hunt Ice Rise and Ward Hunt Ice Shelf, Ellesmere Island, Nunavut, Canada", Journal of Geophysical Research, 109, D22110, 10.1029/2004JD004560, 2004.
Buehner, M., K.R. Thompson, and I. Peterson: "An inverse method for tracking ice motion in the marginal ice zone using sequential satellite images", Journal of Atmospheric and Oceanic Technology, 14, 1455-1466, 1997.
Bushnell, V.C.: "Marvin's Ice Shelf Journey, 1906", Arctic, 9, 166-177, 1956.
Fisheries and Oceans Canada: " Ward Hunt Ice Camp Article" http://www.dfo-mpo.gc.ca/media/infocus-alaune/2009/20090422a-eng.htm, Access: April, 2009.
Chern, J., A. Wu, and S. Lin: "Lesson learned from FORMOSAT-2 mission operations", Acta Astronautica, 59, 344-350, 2006.
Chern, J., A. Wu, Y. Liu, and L. Wu: "An Introduction to FORMOSAT-2’s Global Effectiveness", Small Satellites for Earth Observation, 365, 2008.
Canadian Ice Service: "Ice Shelves - Overview" In: Education Center. http://ice-glaces.ec.gc.ca/App/WsvPageDsp.cfm;jsessionid=7617E615B2A29098F23500D8179DC232?Lang=eng&lnid=40&ScndLvl=no&ID=11893, Access: June 10th, 2009.
Canadian Ice Service: "Ice Shelves - Overview" In: Education Center. http://ice-glaces.ec.gc.ca/App/WsvPageDsp.cfm;jsessionid=7617E615B2A29098F23500D8179DC232?Lang=eng&lnid=40&ScndLvl=no&ID=11893, Access: June 10th, 2009.
Clark, P.U., S.J. Marshall, G.K.C. Clarke, S.W. Hostetler, J.M. Licciardi, and J.T. Teller: "Freshwater Forcing of Abrupt Climate Change During the Last Glaciation", Science, 293, 283-287, 10.1126/science.1062517, 2001.
Collins, I.F., and I.R. McCrae: "Creep buckling of ice shelves and the formation of pressure rollers", Journal of Glaciology, 31, 242-252, 1985.
Comiso, J.C.: "Warming Trends in the Arctic from Clear Sky Satellite Observations", Journal of Climate, 16, 3498-3510, 2003.
Copland, L., D.R. Mueller, and L. Weir: "Rapid Loss of the Ayles Ice Shelf, Ellesmere island, Canada", Geophysical Research Letters, 34, L21501, 10.1029/2007gl031809, 2007.
Crary, A.P.: "Geophysical studies along northern Ellesmere Island", Arctic, 9, 154-165, 1956.
Crary, A.P.: "Arctic ice island and ice shelf studies - Part I", Arctic, 11, 2-42, 1958.
Crary, A.P.: "Arctic ice island and ice shelf studies - Part II", Arctic, 13, 32-50, 1960.
D.A. Rothrock, Y. Yu, and G.A. Maykut: "Thinning of the Arctic Sea-Ice Cover", Geophysical Research Letters, 26, 3469-3472, 1999.
De Angelis, H., and P. Skvarca: "Glacier Surge After Ice Shelf Collapse", Science, 299, 1560-1562, 10.1126/science.1077987, 2003.
Debenhum, F.: "The ice island of the Arctic: an hypothesis", Geographical Review, 44, 495-507, 1954.
Dowdeswell, J.A.: "Atmospheric science - The Greenland Ice Sheet and global sea-level rise", Science, 311, 963-964, 2006.
Environment Canada: "Education Corner - The Calving of the Ward Hunt Ice Shelf" In: Education Corner. http://ice-glaces.ec.gc.ca/WsvPageDsp.cfm?Lang=eng&ID=11895, Access: July 14th, 2009.
Earth Observatory, EOS Project Science Office, NASA Goddard Space Flight Center, USA: "Fires in Southern California" http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=19242&oldid=14603, Access: May 26th, 2009.
Glasser, N.F., and T.A. Scambos: "A structural glaciological analysis of the 2002 Larsen B ice-shelf collapse", Journal of Glaciology, 53, 3-16, 2008.
Gradinger, R., C. Friedrich, and M. Spindler: "Abundance, biomass and composition of the sea ice biota of the Greenland Sea pack ice", Deep Sea Research Part II: Topical Studies in Oceanography, 46, 1457-1472, 1999.
Haarpaintner, J., and G. Spreen: "Use of enhanced-resolution QuikSCAT/SeaWinds data for operational ice services and climate research: Sea ice edge, type, concentration, and drift", Ieee Transactions on Geoscience and Remote Sensing, 45, 3131-3137, 2007.
Hanesiak, J., D. Barber, R. De Abreu, and J. Yackel: "Local and regional albedo observations of arctic first-year sea ice during melt ponding", Journal of Geophysical Research, 106, 2001.
Hattersley-Smith, G.: "The rolls of the Ellesmere Ice Shelf", Arctic, 10, 32–44, 1957.
Hattersley-Smith, G.: "The Ward Hunt Ice Shelf: recent changes of the ice front", Journal of Glaciology, 4, 415–424, 1963.
Hattersley-Smith, G., A. P. Crary, and R.L. Christie: "Northern Ellesmere Island, 1953 and 1954", Arctic, 8, 3-36, 1955.
Hattersley-Smith, G., A. Fuzesy, and S. Evans: Glacier depths in northern Ellesmere Island: airborne radio echo sounding in 1966, Defence Research Board. Department of National Defence, 1969.
Hellmer, H., and D. Olbers: "On the Thermohaline circulation beneath the Filchner-Ronne Ice Shelves", Antarctic Science, 3, 433-442, 2004.
Hibler III, W.D.: "A dynamic thermodynamic sea ice model", Journal of Physical Oceanography, 9, 815-846, 1979.
Hibler III, W.D.: "Ice dynamics". US Army CRREL Monograph, US Army Cold Regions Research Engineering Lab., Hanover, N.H., 1984.
Hochstein, M.P.: "Pressure ridges of the McMurdo Ice Shelf near Scott Base, Antarctica", New Zealand Joournal of Geology and Geophysics, 10, 1165-1168, 1967.
Holdsworth, G.: "Calving from Ward-Hunt Ice Shelf 1961–62", Canadian Journal of Earth Sciences, 8, 299–305, 1971.
Holdsworth, G.: "The surface waveforms on the Ellesmere Island ice shelves and ice islands". Workshop on Extreme Ice Features, Technical Memoir 141 (NRCC 28003), National Research Council of Canada, Banff, Alberta, 1987.
Holdsworth, G., and J. Glynn: "Iceberg calving from floating glaciers by a vibrating mechanism", Nature, 274, 464-466, 1978.
Holdsworth, G., and J.E. Glynn: "A Mechanism for the Formation of Large Icebergs", Journal of Geophysical Research, 86, 10.1029/JC086iC04p03210, 1981.
Hove, V., K.S. P., J.A.E. Gibson, C. Belzile, and W.F. Vincent: "Farthest north lake and fiord populations of calanoid copepods in the Canadian High Arctic", Polar Biology, 24, 303– 307, 2001.
Hughes, T.: "Theoretical calving rates from glaciers along ice walls grounded in water of variable depths", Journal of Glaciology, 38, 282-294, 1992.
Hughes, T.: "Calving bays", Quaternary Science Reviews, 21, 267-282, 2002.
Hulbe, C., R. Johnston, I. Joughin, and T. Scambos: "Marine Ice Modification of Fringing Ice Shelf Flow", Arctic, Antarctic, and Alpine Research, 37, 323-330, 2005.
ITT Visual Information Solutions: "ENVI 4.5" (copyrighted), 2008.
Jeffries, M.: "Ellesmere Island ice shelves and ice islands". In: Richard S. Willams, J., and Ferrigno, J. G., eds. Satellite Image Atlas of Glaciers of the World: North America, USGS, 2002.
Jeffries, M., H. Krause, W. Sackinger, and H. Serson: "Surface tography, thickness and ice-core studies of multiyear landfast sea ice and Ward Hunt Ice Shelf, Northern Ellesmere Island, NWT", Canada's Missing Dimension: Science and History in the Canadian Arctic Islands, 229, 1990.
Jeffries, M.O.: "Ice Shelf Studies off Northern Ellesmere Island, Spring 1983", Arctic, 38, 174-177, 1985.
Jeffries, M.O., and H. Serson: "Recent Changes at the front of Ward Hunt Ice Shelf, Ellesmere Island, NWT", Arctic, 36, 289-290, 1983.
Jeffries, M.O., H.V. Serson, H.R. Krouse, and W.M. Sackinger: "Ice physical-properties, structural characteristics and stratigraphy in Hobson Choice Island and implications for the growth history of East Ward Hunt Ice Shelf, Canadian High Arctic", Journal of Glaciology, 37, 247-260, 1991.
Jenkins, A., and C.S.M. Doake: "Ice-Ocean interaction on Ronne Ice Shelf, Antarctica", Journal of Geophysical Research-Oceans, 96, 791-813, 1991.
Jenkins, A., and D. Holland: "A model study of ocean circulation beneath Filchner-Ronne Ice Shelf, Antarctica- Implications for bottom water formation", Geophysical Research Letters, 29, 34-31, 2002.
Johannessen, O., L. Bengtsson, M. Miles, S. Kuzmina, V. Semenov, G. Alekseev, A. Nagurnyi, V. Zakharov, L. Bobylev, and L. Pettersson: "Arctic climate change: observed and modelled temperature and sea-ice variability", 2004.
Khorram, S.: "Accuracy assessment of remote sensing-derived change detection". In: Khorram, S., ed. American Society for Photogrammetry Remote Sensing, American Society for Photogrammetry and Remote Sensing, Bethesda, Maryland, 1999.
Koenig, L.S., K.R. Greenaway, M. Dunbar, and G.F. Hattersley-Smith: "Arctic ice islands", Arctic, 5, 67-103, 1952.
Krause, P.F., and K. Flood: "Weather and climate extremes", Information Bulletin of the Soviet Antarctic Expedition, 89, 1997.
Kruse, F.A., A.B. Lefkoff, J.B. Boardman, K.B. Heidebrecht, A.T. Shapiro, P.J. Barloon, and A.F.H. Goetz: "The Spectral Image Processing System (SIPS)-Interactive Visualization and Analysis of Imaging Spectrometer Data", Remote Sensing of Environment, 44, 145-163, 1993.
Kwok, R., G.F. Cunningham, M. Wensnahan, I. Rigor, H.J. Zwally, and D. Yi: "Thinning and volume loss of the Arctic Ocean sea ice cover: 2003-2008", Journal of Geophysical Research, 114, 10.1029/2009jc005312, 2009.
Kwok, R., J.C. Curlander, R. McConnell, and S.S. Pang: "An ice-motion tracking system at the Alaska SAR facility", Ieee Journal of Oceanic Engineering, 15, 44-54, 1990.
Larour, E., E. Rignot, and D. Aubry: "Modelling of rift propagation on Ronne Ice Shelf, Antarctica, and sensitivity to climate change", Geophysical Research Letters, 31, 16, 2004.
Laybourn-Parry, J., W. C. Quayle, T. Henshaw, A. Ruddell, and H. J.Marchant: "Life on the edge: The plankton and chemistry of Beaver Lake, an ultra-oligotrophic epishelf lake, Antarctica", Freshwater Biology, 46, 1205– 1217, 2001.
Legendre, L., S.F. Ackley, G.S. Dieckmann, B. Gulliksen, R. Horner, T. Hoshiai, I.A. Melnikov, W.S. Reeburgh, M. Spindler, and C.W. Sullivan: "Ecology of sea ice biota", Polar Biology, 12, 429-444, 1992.
Lemke, P., J. Ren, R.B. Alley, I. Allison, J. Carrasco, G. Flato, Y. Fujii, G. Kaser, P. Mote, R.H. Thomas, and T. Zhang: "Observations: Changes in Snow, Ice and Frozen Ground". In: Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and Miller, H. L., eds. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge, United Kingdom and New York, NY, USA., 2007.
Lewis, J.: "Fast normalized cross-correlation", Vision Interface, 10, 120-123, 1995.
Lin, J.-C.: "Applications of FORMOSAT-2 time series imagery on monitoring the spatial and temporal variations of landslide in the catchments of Tseng-Wen reservoir". Earth Sciences Department, National Cheng Kung University, Tainan City, 2007.
Liou, Y.A., J. Lin, A.M. Wu, G.S. Chang, and Ieee: "Study of Arctic and Antarctic ice dynamics and wind field by using Formosat-2 satellite data". IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Ieee, Barcelona, SPAIN, 2007.
Lipps, J.H., T.E. Ronan, and T.E. Jr. Delaca: "Life Below the Ross Ice Shelf, Antarctica", Science, 203, 447-449, 10.1126/science.203.4379.447, 1979.
Liu, A.K., S. Martin, and R. Kwok: "Tracking of ice edges and ice floes by wavelet analysis of SAR images", Journal of Atmospheric and Oceanic Technology, 14, 1187-1198, 1997.
Liu, C.-C.: "Processing of FORMOSAT-2 daily revisit imagery for site surveillance", Ieee Transactions on Geoscience and Remote Sensing, 44, 3206-3214, 10.1109/tgrs.2006.880625, 2006.
Liu, C.-C.: "Formosat-2 Automatic Image Processing System 8.0" (copyrighted), 2009.
Liu, C.-C., Y.-C. Chang, S. Huang, F. Wu, and A.-M. Wu: "First high-spatial-and high-temporal-resolution optical imagery of polar regions from Formosat-2 (slides)". Fall Meeting, EOS Transaction, AGU, San Francisco, USA, 2007a.
Liu, C.-C., Y.-C. Chang, S. Huang, F. Wu, A.-M. Wu, S. Kato, and Y. Yamaguchi: "Short Note: First space-borne high-spatial-resolution optical imagery of the Antarctic from Formosat-2", Antarctic Science, 20, 605-606, doi:10.1017/S0954102008001338, 2008a.
Liu, C.-C., Y.-C. Chang, S. Huang, S.-Y. Yan, F. Wu, A.-M. Wu, S. Kato, and Y. Yamaguchi: "Monitoring the dynamics of ice shelf margins in Polar Regions with high-spatial- and high-temporal-resolution space-borne optical imagery", Cold Regions Science and Technology, 55, 14-22, 2009a.
Liu, C.-C., and P.-L. Chen: "Automatic extraction of ground control regions and orthorectification of remote sensing imagery", Optic Express, 17, 7970-7984, 2009b.
Liu, C.-C., J.-G. Liu, C.-W. Lin, A.-M. Wu, S.-H. Liu, and C.-L. Shieh: "Image processing of FORMOSAT-2 data for monitoring the South Asia tsunami", International Journal of Remote Sensing, 28, 3093-3111, 2007b.
Liu, C.-C., C.-L. Shieh, C.-A. Wu, and M.-L. Shieh: "Change Detection of Gravel Mining on Riverbeds from the Multi-temporal and High-spatial-resolution Formosat-2 Imagery", River Research and Applications, 24, 1-17, 10.1002/rra.1210, 2008b.
Liu, C.-C., C.-A. Wu, M. Shieh, J. Liu, C. Lin, and C. Shieh: "Monitoring the illegal quarry mining of gravel on the riverbed using daily revisit FORMOSAT-2 imagery". Geoscience and Remote Sensing Symposium, 2005. IGARSS '05. Proceedings. 2005 IEEE International, 2005.
Liu, J.-G., and J. Ma: "Imageodesy on MPI & GRID for co-seismic shift study using satellite optical imagery". UK e-Science All Hands Meeting, Nottingham, U.K., 2004.
Liu, J.-G., P.-J. Mason, and J. Ma: "Measurement of the left-lateral displacement of Ms 8.1 Kunlun earthquake on 14 November 2001 using Landsat-7 ETM+ imagery", International Journal of Remote Sensing, 27, 1875-1891, 2006.
Loset, S., K. Shkhinek, O.T. Gudmestad, P. Strass, E. Michalenko, R. Frederking, and T. Kana: "Comparison of the physical environment of some Arctic seas", Cold Regions Science and Technology, 29, 201-214, 1999.
Lyons, J., and J. Mielke: "Holocene history of a portion of northernmost Ellesmere Island", Arctic, 26, 314-323, 1973.
MacAyeal, D., and G. Holdsworth: "An investigation of low-stress ice rheology on the Ward-Hunt Ice Shelf", Journal of Geophysical Research, 91, 6347-6358, 1986.
MacAyeal, D., E. Rignot, and C. Hulbe: "Ice-shelf dynamics near the front of Filchner-Ronne Ice Shelf, Antarctica, revealed by SAR interferometry: model/interferogram comparison", Journal of Glaciology, 1998.
MacAyeal, D.R., E.A. Okal, R.C. Aster, J.N. Bassis, K.M. Brunt, L.M. Cathles, R. Drucker, H.A. Fricker, Y.-J. Kim, S. Martin, M.H. Okal, O.V. Sergienko, M.P. Sponsler, and J.E. Thom: "Transoceanic wave propagation links iceberg calving margins of Antarctica with storms in tropics and Northern Hemisphere", Geophysical Research Letters, 33, 10.1029/2006gl027235, 2006.
MacAyeal, D.R., T.A. Scambos, C.L. Hulbe, and M.A. Fahnestock: "Catastrophic ice-shelf break-up by an ice-shelf-fragment-capsize mechanism", Journal of Glaciology, 49, 22-36, 2003.
Martinson, D.G., S.E. Stammerjohn, R.A. Iannuzzi, R.C. Smith, and M. Vernet: "Western Antarctic Peninsula physical oceanography and spatio-temporal variability", Deep-Sea Research Part II -Topical Studies in Oceanography, 55, 1964-1987, 10.1016/j.dsr2.2008.04.038, 2008.
Mawson, D., and J. Condon: The home of the blizzard, Heinemann London, 1915.
Mercer, J.: "West Antarctic ice sheet and CO2 greenhouse effect: a threat of disaster", 1978.
Trent University News Release, by Derek Mueller: "Scientists Report Massive Ice Shelf Loss During Summer of 2008 - Canada's Ice Shelves Lose 23 % of their Area, Number Reduced from Five to Four" http://www.people.trentu.ca/~dmueller/iceshelfloss2008/20080902_IceShelfLoss.pdf, Access: March 8, 2009.
Mueller, D., W. Vincent, and M. Jeffries: "Environmental gradients, fragmented habitats, and microbiota of a northern ice shelf cryoecosystem, Ellesmere Island, Canada", Arctic, Antarctic, and Alpine Research, 38, 593-607, 2006a.
Mueller, D.R., and W.F. Vincent: "Microbial habitat dynamics and ablation control on the Ward Hunt Ice Shelf", Hydrological Processes, 20, 857-876, 10.1002/hyp.6113, 2006b.
Mueller, D.R., W.F. Vincent, and M.O. Jeffries: "Break-up of the largest Arctic ice shelf and associated loss of an epishelf lake", Geophysical Research Letters, 30, 2031, 10.1029/2003gl017931, 2003.
Narod, B., G. Clarke, and B. Prager: "Airborne UHF radar sounding of glaciers and ice shelves, northern Ellesmere Island, Arctic Canada", Canadian Journal of Earth Sciences, 25, 95-105, 1988.
Nath, P., and D. Vaughan: "Subsurface crevasse formation in glaciers and ice sheets", Journal of Geophysical Research, 108, 10.1029, 2003.
National Snow and Ice Data Center: "Arctic Sea Ice News and Analysis: Arctic Sea Ice Down to Second-Lowest Extent; Likely Record-Low Volume" http://nsidc.org/news/press/20081002_seaice_pressrelease.html, Access: 9 March, 2009.
National Snow and Ice Data Center: "The Cryosphere - Where the World is Frozen: Glossary" http://nsidc.org/cgi-bin/words/glossary.pl, Access: June 7th, 2009.
National Snow and Ice Data Center: "Processes: Dynamics" In: Education Center - All About Sea Ice. http://nsidc.org/seaice/processes/dynamics.html, Access: July 14th, 2009.
National Snow and Ice Data Center "State of the Cryosphere: Ice Shelves" In: State of the Cryosphere. http://nsidc.org/sotc/iceshelves.html, Access: 17 March, 2009.
Padman, L., H.A. Fricker, R. Coleman, S. Howard, and L. Erofeeva: "A new tide model for the Antarctic ice shelves and seas". In: Winther, J. G. S. R., ed, Int Glaciological Soc, 2002.
Peary, R.: Nearest the Pole: a narrative of the Polar expedition of the Peary Arctic club in the SS Roosevelt, 1905-1906, Hutchinson, London, 1907.
Perovich, D.K.: "The Optical Properties of Sea Ice". Cold Regions Research and Engineering Laboratory, U.S. Army Corps of Engineers, Hanover, New Hampshire, 1996.
Polyakov, I., G. Alekseev, R. Bekryaev, U. Bhatt, R. Colony, M. Johnson, V. Karklin, A. Makshtas, D. Walsh, and A. Yulin: "Observationally based assessment of polar amplification of global warming", Geophysical Research Letters, 29, 1878, 2002.
Price, S., and I. Whillans: "Crevasse patterns at the onset to Ice Stream B, West Antarctica", Journal of Glaciology, 47, 29-36, 2001.
Reeh, N.: "On the calving of ice from floating glaciers and ice shelves", Journal of Glaciology, 7, 215-232, 1968.
Rees, G.W.: "Remote Sensing Systems for Observation of the Earth's Surface". Remote sensing of snow and ice, CRC Press, Taylor & Francis Group, 2006.
Renner, R.: "Surface elevations on the Larsen Ice Shelf", British Antarctic Survey Bulletin, 19, 1–8, 1969.
Rignot, E.: "Tidal Flexure, Ice Velocities, and Ablation Rates of Peterman Gletscher, Greenland", 1996.
Rignot, E.: "Changes in ice dynamics and mass balance of the Antarctic ice sheet". Royal Society, 2006.
Rignot, E., J.L. Bamber, M.R. van den Broeke, C. Davis, Y. Li, W.J. van de Berg, and E. van Meijgaard: "Recent Antarctic ice mass loss from radar interferometry and regional climate modelling", Nature Geoscience, 1, 106-110, 2008.
Rignot, E., and S.S. Jacobs: "Rapid bottom melting widespread near Antarctic Ice Sheet grounding lines", Science, 296, 2020-2023, 2002.
Rist, M.A., P.R. Sammonds, S.A.F. Murrell, P.G. Meredith, C.S.M. Doake, H. Oerter, and K. Matsuki: "Experimental and theoretical fracture mechanics applied to Antarctic ice fracture and surface crevassing", Journal of Geophysical Research-Solid Earth, 104, 2973-2987, 1999.
Rist, M.A., P.R. Sammonds, H. Oerter, and C.S.M. Doake: "Fracture of Antarctic shelf ice", Journal of Geophysical Research, 107, 2002.
Rouse, J.W.: "Arctic ice type identification by radar", Proceedings of the Ieee, 57, 605-, 1969.
Sackinger, W., M. Jeffries, F. Li, and M. Lu: "Ice island creation, drift, recurrences, mechanical properties, and interactions with arctic offshore oil production structures. Final report". DOE/MC/25027--3112, Alaska Univ., Fairbanks, AK (United States). Geophysical Inst., 1991.
Scambos, T., C. Hulbe, and M. Fahnestock: "Climate-induced ice shelf disintegration in the Antarctic Peninsula", Antarctic Peninsula Climate Variability: Historical and Paleoenvironmental Perspectives, 79–92, 2003.
Scambos, T.A., H.A. Fricker, C.-C. Liu, J.A. Bohlander, J. Fastook, A. Sargent, R. Massom, and A.-M. Wu.: "Ice shelf disintegration by plate bending and hydrofracture: Satellite observations and model results of the 2008 Wilkins Ice Shelf breakup", Earth and Planetary Science Letters, 280, 51-60 doi:10.1016/j.epsl.2008.12.027, 2009a.
Scambos, T.A., C. Hulbe, M. Fahnestock, and J. Bohlander: "The link between climate warming and break-up of ice shelves in the Antarctic Peninsula", Journal of Glaciology, 46, 516-530, 2000.
Scambos, T.A., and C.-C. Liu: "A Closer Look at Polar Ice: Formosat-2 and Glacier Changes in the Arctic and Antarctic". Formosat-2 5th Anniversary Conference, National Space Organization, Taiwan, R.O.C, Hsinchu, Taiwan, R.O.C, 2009b.
Schoof, C.: "Ice sheet grounding line dynamics: Steady states, stability, and hysteresis", Journal of Geophysical Research, 112, 1-19, 2007.
Schulson, E.M.: "Brittle failure of ice", Engineering Fracture Mechanics, 68, 1839-1887, 2001.
EOS Observatory, by Michon Scott: "Rapid Retreat - Ice Shelf Loss along Canada's Ellesmere Coast" http://earthobservatory.nasa.gov/Features/Ellesmere/, Access: March 9, 2009.
Serreze, M.C., M.M. Holland, and J. Stroeve: "Perspectives on the Arctic's Shrinking Sea-Ice Cover", Science, 315, 1533-1536, 10.1126/science.1139426, 2007.
Shackleton, E.: The heart of the Antarctic: being the story of the British Antarctic expedition 1907-1909, W. Heinemann, 1909.
Shepherd, A., D. Wingham, T. Payne, and P. Skvarca: "Larsen Ice Shelf Has Progressively Thinned", Science, 302, 856-859, 10.1126/science.1089768, 2003.
Smith, R.B.: "The folding of a strongly non-Newtonian layer", American Journal of Science, 279, 272-287, 1979.
Stammerjohn, S.E., D.G. Martinson, R.C. Smith, and R.A. Iannuzzi: "Sea ice in the western Antarctic Peninsula region: Spatio-temporal variability from ecological and climate change perspectives", Deep-Sea Research Part II -Topical Studies in Oceanography, 55, 2041-2058, 10.1016/j.dsr2.2008.04.026, 2008.
Stroeve, J., M. Holland, W. Meier, T. Scambos, and M. Serreze: "Arctic sea ice decline: Faster than forecast", Geophysical Research Letters, 34, 9501, 2007.
Trenberth, K.E., P.D. Jones, P. Ambenje, R. Bojariu, D. Easterling, A. Klein Tank, D. Parker, F. Rahimzadeh, J.A. Renwick, M. Rusticucci, B. Soden, and P. Zhai: "Observations: Surface and Atmospheric Climate Change". In: Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and Miller, H. L., eds. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge, United Kingdom and New York, NY, USA., 2007.
van den Broeke, M.: "Strong surface melting preceded collapse of Antarctic Peninsula ice shelf", Geophysical Research Letters, 32, 2005.
van der Veen, C.J.: "Fracture mechanics approach to penetration of bottom crevasses on glaciers", Cold Regions Science and Technology, 27, 213-223, 1998a.
van der Veen, C.J.: "Fracture mechanics approach to penetration of surface crevasses on glaciers", Cold Regions Science and Technology, 27, 31-47, 1998b.
van der Veen, C.J.: "Fracture propagation as means of rapidly transferring surface meltwater to the base of glaciers", Geophysical Research Letters, 34, L01501, 10.1029/2006gl028385, 2007.
Vaughan, D.G.: "Relating the Occurrence of Crevasses to Surface Strain Rates", Journal of Glaciology, 39, 255-266, 1993.
Vaughan, D.G.: "Tidal flexure at ice shelf margins", Journal of Geophysical Research, 100, 6213–6224, 10.1029/94jb02467, 1995.
Vaughan, D.G., and C.S.M. Doake: "Recent atmospheric warming and retreat of ice shelves on the Antarctic Peninsula", Nature, 379, 328-331, 1996.
Vincent, W., D. Mueller, and S. Bonilla: "Ecosystems on ice: the microbial ecology of Markham Ice Shelf in the high Arctic", Cryobiology, 48, 103-112, 2004.
Vincent, W.F., J.A.E. Gibson, and M.O. Jeffries: "Ice-shelf collapse, climate change and habitat loss in the Canadian High Arctic", Polar Record, 31, 133-142, 2001.
Vincent, W.F., J.A.E. Gibson, R. Pienitz, V. Villeneuve, P.A. Broady, P.B. Hamilton, and C. Howard-Williams: "Ice shelf microbial ecosystems in the high Arctic and implications for life on snowball earth", Naturwissenschaften, 87, 137-141, 2000.
Walker, E.R., and P. Wadhams: "Thick Sea-ice Floes", Arctic, 32, 140-147, 1979.
Arizona University World Meteorological Organization: "World: Lowest Temperature" In: World Weather / Climate Extremes Archive. http://wmo.asu.edu/world-lowest-temperature, Access: July 10th, 2009.
Wendler, G., C. Stearns, G. Weidner, G. Dargaud, and T. Parish: "On the extraordinary katabatic winds of Adelie Land", Journal of Geophysical Research, 102, 10.1029/96jd03438, 1996.
Whillans, I.M., and C.J. Merry: "Analysis of a shear zone where a tractor fell into a crevasse, western side of the Ross Ice Shelf, Antarctica", Cold Regions Science and Technology, 33, 1-17, 2001.
Whillans, I.M., and Y.H. Tseng: "Automatic tracking of crevasses on satellite images", Cold Regions Science and Technology, 23, 201-214, 1995.
Wu, S.Y., and A.K. Liu: "Towards an automated ocean feature detection, extraction and classification scheme for SAR imagery", International Journal of Remote Sensing, 24, 935-951, 2003.
Yasuhara, M., T.M. Cronin, P.B. deMenocal, H. Okahashi, and B.K. Linsley: "Abrupt climate change and collapse of deep-sea ecosystems", Proceedings of the National Academy of Sciences of the United States of America, 105, 1556-1560, 10.1073/pnas.0705486105, 2008.
Zwally, H.J., W. Abdalati, T. Herring, K. Larson, J. Saba, and K. Steffen: "Surface melt-induced acceleration of Greenland ice-sheet flow", Science, 297, 218-222, 2002.