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Monitoring Glacier Veloci)es in the Russian High Arc)c Garth N. Ornelas 1, Dr. Ma8hew E. Pritchard 2, Dr. Michael J. Willis 2, Andrew K. Melkonian 2 (1)  -­‐ Student at Southwestern University Dept. Of Physics (2)  -­‐ Department of Earth & Atmospheric Sciences, Cornell University Introduc)on Discussion Results The seasonal varia)on of the images selected plays a large role in the velocity of the ice stream There is a gradual increase in velocity from the spring to summer months as shown below We analyze )dewater glacier veloci)es in the Academy of Sciences ice cap on Komsomolets island, Severnaya Zemlya Archipelago of the Russian High Arc)c. Tidewater glaciers are a major source of ice loss in the area, which contributes to sea level rise We compare observed veloci)es to previous studies to constrain the seasonal variability of current front veloci)es and determine if there is inter-­‐annual accelera)on, which would imply accelerated mass loss Seasonal VariaXons in Ice Stream C 80˚28'N
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Figure 3: Academy of Sciences Ice Cap glacial veloci)es (2009–2012) (Stewart 2014) Data 0 km
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The data we used was obtained using Worldview 1 & 2 satellite imagery between 2011 and 2013 obtained from the Polar Geospa)al Center at the University of Minnesota. 2.0
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Figure 8: Apr 15-­‐ Sept 6 (2011) Velocity (m/day)
Figure 2: Zoom in on Academy of Sciences Ice Cap (Stewart 2014) 2.0
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Figure 9: Apr 21 –Jul 1 (2013) 97˚00'E
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Figure 10: July 1 – August 12 (2013) 80˚34'N
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Methods Two images are selected for use in an automa)c pixel tracking process. Crevasses are used to track ice stream movement. If movement occurs in bedrock, the uncertainty in the measurements increases. We obtain veloci)es from the )me span and the distance tracked by the same feature (usually a crevasse). 97˚00'E
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Figure 4: Ice Stream D Jul. 1, 2013 (WV02) – Aug. 12, 2013 (WV01) 80˚28'N
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Figure 6: Academy of Sciences Ice Cap glacial veloci)es (1995) (Moholdt et al., 2012a) 0 km
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Figure 5: Ice Stream B Apr. 25, 2013 (WV01) – Jul. 1, 2013 (WV02) Acknowledgements 80˚26'N
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Comparing our data to past work shows a definite increase in glacier velocity. For overlapping )me intervals we find out data to be consistent with work done by Stewart. The data we gathered on ice streams A and glacier #13 was ul)mately inconclusive, but data for ice streams B, C, and D is reliable. 1 km
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Velocity (m/day)
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Figure 11: Ice Stream D (WV01) 97˚08'E
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Figure 7: Ice Stream C Jul. 1, 2013 (WV02) – Aug. 12, 2013 (WV01) The author would like to thank the RESESS program, UNAVCO, ExxonMobil, the University of Minnesota, and NASA for the funding and encouragement needed to complete this project. References Table of glacier veloci)es (m/ day) Figures 1,3 – Stewart, J. Adam., 2014. Monitoring Glacial Velocity Varia)on In The Russian High Arc)c Using Remote Sensing. Senior thesis, EAS Deprtment of Cornell University. Figure 2 – Relief from Interna)onal Bathymetric Chart of the Arc)c Ocean. Ice from Atlas of the Cryosphere. Figure 4 -­‐ Moholdt, G., T. Heid, T. Benham, and J. A. Dowdeswell, 2012. Dynamic instability of marine-­‐termina)ng glacier basins of Academy of Sciences Ice Cap, Russian High Arc)c. Annals of Glaciology 53:1–9. Figure 11-­‐ Digital Globe Image Finder Figure 1: Flow chart of pixel tracking process. (Stewart 2014) 97˚15'E
Conclusions 1 km
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