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Shad O'Neel

Title: Research Geophysicist
Address: 4210 University Dr., Anchorage, AK 99508-4626
Phone: (907) 786-7088
Fax: (907) 786-7150

Image of Shad  O'Neel

Education and/or Training

Ph.D.2006Institute of Arctic and Alpine Research, Dept. of Geological Sciences, University of Colorado BoulderGeophysics
M.S.2000Geophysical Institute, University of Alaska FairbanksGeophysics
B.A.1997University of MontanaEnvironmental Geology

Areas of Specialization and/or Research Interests

Glacier-climate interactions and sea level rise: Melting of glaciers and ice-sheets provides the largest eustatic contribution to global sea level rise. Terrestrial glaciers respond to temperature changes, but nonlinear dynamic processes at marine-terminating glaciers are important, yet poorly constrained. Such dynamic instabilities allow rapid flow and even faster iceberg calving, complicating estimates of sea level contributions.

Small glaciers: The world's glaciers and ice caps, not the great ice sheets, are changing most rapidly and will have the largest and most immediate impact on Earth's population.

Glacier-generated seismicity: Information pertaining to both flow and calving are stored in the seismograms produced by glaciers, yet these signals are poorly understood. Automatic event detection and time-series development, analysis of site and path effects, frequency-magnitude distributions are underway and serve to clarify the source physics of iceberg calving.

Photogrammetry: Dynamical information can be extracted from images acquired from spaceborne, airborne and terrestrial photography. Time-lapse sequences provide robust time series of change, and I am working on automatic processing algorithms to streamline data acquisition.

Professional Experience

2007 - 2008Postdoctoral Scholar, Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, UC San Diego
2007 - 2008Geophysical Institute, University of Alaska Fairbanks
2007Lecturer at University of Colorado Boulder, graduate level glaciology
2001 - 2003Geodetic Engineer at UNAVCO in Boulder, CO; Assisted NSF research projects with GPS deployment and data processing as a Glacier GPS specialist.

Professional Activities and/or Memberships

Affiliate of University of Colorado Boulder's Institute of Arctic and Alpine Research (INSTAAR)
Affiliate of Univeristy of Alaska Fairbanks, Department of Geology and Geophysics
American Geophysical Union, Cryosphere Focus Group Executive Committee
PASSCAL (Program for Array Seismic Studies of the Continental Lithosphere) Standing Committee
International Glaciological Society

Websites of Interest

Featured Data Releases

O'Neel, S. R., et al, 2017, Raw Ground Penetrating Radar Data on North America Glaciers (ver. 2.0, August 2017): U.S. Geological Survey data release,

O'Neel, S. R., Sass, L. C., McNeil, C. and McGrath, D., 2016, USGS Alaska Benchmark Glacier Mass Balance Data - Phase 1; Gulkana and Wolverine Glaciers: U.S. Geological Survey data release,


Total pubs: 45

McGrath, D., L. C. Sass, S. R. O'Neel, A. A. Arendt, and C. Kienholz. 2017. Hypsometric control on glacier mass balance sensitivity in Alaska and northwest Canada. Earth's Future 5(3):324-336. doi:10.1002/2016EF000479 [Details] [Full Publication]

Liljedahl, A. K., A. Gädeke, S. R. O'Neel, T. A. Gatesman, and T. A. Douglas. 2017. Glacierized headwater streams as aquifer recharge corridors, subarctic Alaska. Geophysical Research Letters 44(13). doi:10.1002/ 2017GL073834 [Details] [Full Publication]

Boldt Love, K., B. Hallet, T. L. Pratt, and S. R. O'Neel. 2016. Observations and modeling of fjord sedimentation during the 30 year retreat of Columbia Glacier, AK. Journal of Glaciology 62(234):778-793. doi:10.1017/jog.2016.67 [Details] [Full Publication]

Wolken, G. J., M. Sharp, L. M. Andreassen, A. A. Arendt, D. Burgess, J. G. Cogley, L. Copland, J. Kohler, S. R. O'Neel, M. Pelto, L. Thomson, and B. Wouters. 2016. Glaciers and Icecaps outside Greenland [in "State of the Climate in 2015"]. Bulletin of the American Meteorological Society 97(8):S142-S145. doi:10.1175/2016BAMSStateoftheClimate.1 [Details] [Full Publication]

Enderlin, E. M., G. S. Hamilton, S. R. O'Neel, T. C. Bartholomaus, M. Morlighem, and J. W. Holt. 2016. An Empirical Approach for Estimating Stress-Coupling Lengths for Marine-Terminating Glaciers. Frontiers in Earth Science - Cryospheric Sciences 4(104). doi:10.3389/feart.2016.00104 [Details] [Full Publication]

Larsen, C. F., E. W. Burgess, A. A. Arendt, S. R. O'Neel, A. J. Johnson, and C. Kienholz. 2015. Surface melt dominates Alaska glacier mass balance. Geophysical Research Letters 42. doi:10.1002/2015GL064349 [Details] [Full Publication]

Hood, E. W., T. J. Battin, J. B. Fellman, S. R. O'Neel, and R. G. M. Spencer. 2015. Storage and release of organic carbon from glaciers and ice sheets. Nature Geoscience 8:91-96. doi:10.1038/ngeo2331 [Details] [Full Publication]

Pettit, E. C., K. M. Lee, J. P. Brann, J. A. Nystuen, P. S. Wilson, and S. R. O'Neel. 2015. Unusually loud ambient noise in tidewater glacier fjords: a signal of ice melt. Geophysical Research Letters 42(7):2309-2316. doi:10.1002/2014GL062950 [Details] [Full Publication]

O'Neel, S. R., E. W. Hood, A. Bidlack, S. W. Fleming, M. L. Arimitsu, A. A. Arendt, E. W. Burgess, C. J. Sergeant, A. H. Beaudreau, K. Timm, G. D. Hayward, J. H. Reynolds, and S. Pyare. 2015. Icefield-to-Ocean Linkages across the Northern Pacific Coastal Temperate Rainforest Ecosystem. BioScience 65(5):499-512. doi:10.1093/biosci/biv027 [Details] [Full Publication]

Stearns, L. A., G. S. Hamilton, C. J. van der Veen, D. C. Finnegan, S. R. O'Neel, J. B. Scheick, and D. E. Lawson. 2015. Glaciological and marine geological controls on terminus dynamics of Hubbard Glacier, southeast Alaska. Journal of Geophysical Research: Earth Surface 120(6):1065-1081. doi:10.1002/2014JF003341 [Details] [Full Publication]

McGrath, D., L. C. Sass, S. R. O'Neel, A. A. Arendt, G. J. Wolken, A. Gusmeroli, C. Kienholz, and C. J. McNeil. 2015. End-of-winter snow depth variability on glaciers in Alaska. Journal of Geophysical Research: Earth Surface 120. doi:10.1002/2015JF003539 [Details] [Full Publication]

Bartholomaus, T. C., J. M. Amundson, J. I. Walter, S. R. O'Neel, M. E. West, and C. F. Larsen. 2015. Subglacial discharge at tidewater glaciers revealed by seismic tremor. Geophysical Research Letters 42:6391-6398. doi:10.1002/2015GL064590 [Details] [Full Publication]

Fleming, S. W., E. W. Hood, H. E. Dahlke, and S. R. O'Neel. 2015. Seasonal flows of international British Columbia-Alaska rivers: the nonlinear influence of ocean-atmosphere circulation patterns. Advances in Water Resources 87:42-55. doi:10.1016/j.advwatres.2015.10.007 [Details] [Full Publication]

Bartholomaus, T. C., C. F. Larsen, M. E. West, S. R. O'Neel, E. C. Pettit, and M. Truffer. 2015. Tidal and seasonal variations in calving flux observed with passive seismology. Journal of Geophysical Research: Earth Surface 120(11):2318-2337. doi:10.1002/2015JF003641 [Details] [Full Publication]

O'Neel, S. R., E. W. Hood, A. A. Arendt, and L. C. Sass. 2014. Assessing streamflow sensitivity to variations in glacier mass balance. Climatic Change 123(2):329-341. doi:10.1007/s10584-013-1042-7 [Details] [Full Publication]

Heeszel, D. S., H. A. Fricker, J. N. Bassis, S. R. O'Neel, and F. Walter. 2014. Seismicity within a propagating ice shelf rift: The relationship between icequake locations and ice shelf structure. Journal of Geophysical Research: Earth Surface 119(4):731-744. doi:10.1002/2013JF002849 [Details] [Full Publication]

Timm, K., S. R. O'Neel, E. W. Hood, and A. Bidlack. 2014. From icefield to ocean explore the many ways that glaciers influence Alaska's coastal ecosystems. USGS Alaska Climate Center web site. Retrieved from [Details] [Full Publication]

Åström, J. A., D. Vallot, M. Schäfer, E. Z. Welty, S. R. O'Neel, T. C. Bartholomaus, Y. Liu, T. I. Riikilä, T. Zwinger, J. Timonen, and J. C. Moore. 2014. Termini of calving glaciers as self-organized critical systems. Nature Geoscience 7:874-878. doi:10.1038/NGEO2290 [Details] [Full Publication]

Bartholomaus, T. C., C. F. Larsen, and S. R. O'Neel. 2013. Does calving matter? Evidence for significant submarine melt. Earth and Planetary Science Letters 380:21-30. doi:10.1016/j.epsl.2013.08.014 [Details] [Full Publication]

Arendt, A. A., S. Luthcke, A. Gardner, S. R. O'Neel, D. Hill, G. Moholdt, and W. Abdalati. 2013. Analysis of a GRACE global mascon solution for Gulf of Alaska glaciers. Journal of Glaciology 59(217):913-924. doi:10.3189/2013JoG12J197 [Details] [Full Publication]

Welty, E. Z., T. C. Bartholomaus, S. R. O'Neel, and W. T. Pfeffer. 2013. Cameras as clocks. Journal of Glaciology 59(214):275-286. doi:10.3189/2013JoG12J126 [Details] [Full Publication]

Cook, S., T. Zwinger, I. C. Rutt, S. R. O'Neel, and T. Murray. 2012. Testing the effect of water in crevasses on a physically-based calving model. Annals of Glaciology 53(60):90-96. doi:10.3189/2012AoG60A107 [Details] [Full Publication]

Bartholomaus, T. C., C. F. Larsen, S. R. O'Neel, and M. E. West. 2012. Calving seismicity form iceberg-sea surface interactions. Journal of Geophysical Research 117(F4):F04029. doi:10.1029/2012JF002513 [Details] [Full Publication]

McNabb, R. W., R. Hock, S. R. O'Neel, L. A. Rasmussen, Y. Ahn, M. Bruan, H. Conway, S. Herreid, I. Joughin, W. T. Pfeffer, B. E. Smith, and M. Truffer. 2012. Using surface velocities to calculate ice thickness and bed topography: a case study at Columbia Glacier, Alaska, USA. Journal of Glaciology 58(212):1151-1164. doi:10.3189/2012JoG11J249 [Details] [Full Publication]

Pettit, E. C., J. A. Nystuen, and S. R. O'Neel. 2012. Listening to glaciers: Passive hydroacoustics near marine-terminating glaciers. Oceanography 25(3):104-105. doi:10.5670/oceanog.2012.81 [Details] [Full Publication]

Walter, F., J. M. Amundson, S. R. O'Neel, M. Truffer, M. Fahnestock, and H. A. Fricker. 2012. Analysis of low-frequency seismic signals generated during a multiple-iceberg calving event at Jakobshavn Isbræ, Greenland. Journal of Geophysical Research: Earth Surface 117:F01036. doi:10.1029/2011JF002132 [Details] [Full Publication]

O'Neel, S. R. 2012. Surface mass balance of Columbia Glacier, Alaska, 1978 and 2010 balance years. USGS Data Series 676, 8 p. [Details] [Full Publication]

March, R. S. and S. R. O'Neel. 2011. Gulkana Glacier, Alaska—Mass balance, meteorology, and water measurements, 1997-2001. USGS Scientific Investigations Report 2011-5046, 72 p. [Details] [Full Publication]

Post, A., S. R. O'Neel, R. J. Motyka, and G. Streveler. 2011. A complex relationship between calving glaciers and climate. EOS, Transactions American Geophysical Union 92(37):305-306. doi:10.1029/2011EO370001 [Details] [Full Publication]

Brunt, K. M., H. A. Fricker, L. Padman, T. A. Scambos, and S. R. O'Neel. 2010. Mapping the grounding zone of Ross Ice Shelf using ICESat laser altimetry. Annals of Glaciology 51(55):71-79. [Details]

West, M. E., C. F. Larsen, M. Truffer, S. R. O'Neel, and L. LeBlanc. 2010. Glacier microseismicity. Geology 38(4):319-322. doi:10.1130/G30606.1 [Details] [Full Publication]

Van Beusekom, A. E., S. R. O'Neel, R. S. March, L. C. Sass, and L. H. Cox. 2010. Re-analysis of Alaskan benchmark glacier mass-balance data using the index method. USGS Scientific Investigations Report 2010-5247, 16 p. [Details] [Full Publication]

Walter, F. S., S. R. O'Neel, D. E. McNamara, W. T. Pfeffer, J. N. Bassis, and H. A. Fricker. 2010. Iceberg calving during transition from grounded to floating ice: Columbia Glacier, Alaska. Geophysical Research Letters 37(15). doi:10.1029/2010GL043201 [Details] [Full Publication]

O'Neel, S. R., C. F. Larsen, N. Rupert, and R. Hansen. 2010. Iceberg calving as a primary source of regional-scale glacier-generated seismicity in the St. Elias Mountains, Alaska. Journal of Geophysical Research 115(F04034). doi:10.1029/2009JF001598 [Details] [Full Publication]

Josberger, E. G., W. R. Bidlake, R. S. March, and S. R. O'Neel. 2009. Fifty-Year Record of Glacier Change Reveals Shifting Climate in the Pacific Northwest and Alaska, USA. USGS Fact Sheet 2009-3046, 4 p. [Details] [Full Publication]

Pfeffer, W. T., J. T. Harper, and S. R. O'Neel. 2008. Kinematic constraints on glacier contributions to 21st-century sea-level rise. Science 321(5894):1340-1343. doi:10.1126/science.1159099 [Details] [Full Publication]

O'Neel, S. R., H. P. Marshall, D. E. McNamara, and W. T. Pfeffer. 2007. Detection and analysis of icequakes at Columbia Glacier, AK. Journal of Geophysical Research 112:F02S13. doi:10.1029/2006JF000595 [Details] [Full Publication]

O'Neel, S. R. and W. T. Pfeffer. 2007. Source mechanics for monochromatic icequakes produced during iceberg calving at Columbia Glacier, AK. Geophysical Research Letters 34:L22502. doi:10.1029/2007GL031370 [Details] [Full Publication]

Meier, M. F., M. B. Dyurgerov, U. K. Rick, S. R. O'Neel, W. T. Pfeffer, R. S. Anderson, S. P. Anderson, and A. F. Glazovsky. 2007. Glaciers dominate eustatic sea-level rise in the 21st century. Science 317(5841):1064-1067. doi:10.1126/science.1143906 [Details] [Full Publication]

O'Neel, S. R., W. T. Pfeffer, R. M. Krimmel, and M. F. Meier. 2005. Evolving force balance at Columbia Glacier, during its rapid retreat. Journal of Geophysical Research 110:F03012. doi:10.1029/2005JF000292 [Details] [Full Publication]

Harper, J. T., N. F. Humphrey, W. T. Pfeffer, T. Fudge, and S. R. O'Neel. 2005. Evolution of subglacial water pressure along a glacier's length. Annals of Glaciology 40:31-36. [Details] [Full Publication]

Anderson, R. S., S. P. Anderson, K. R. MacGregor, S. R. O'Neel, C. A. Riihimaki, E. D. Waddington, and M. G. Loso. 2004. Strong feedbacks between hydrology and sliding of a small alpine glacier. Journal of Geophysical Research 109:F03005. doi:10.1029/2004JF000120 [Details] [Full Publication]

O'Neel, S. R., K. A. Echelmeyer, and R. J. Motyka. 2003. Short-term variations in calving of a tidewater glacier: LeConte Glacier, Alaska. Journal of Glaciology 49(167):587-598. doi:10.3189/172756503781830430 [Details] [Full Publication]

Motyka, R. J., S. R. O'Neel, C. L. Connor, and K. A. Echelmeyer. 2003. Twentieth century thinning of Mendenhall Glacier, Alaska, and its relationship to climate, lake calving, and glacier run-off. Global and Planetary Change 35(1-2):93-112. doi:10.1016/S0921-8181(02)00138-8 [Details] [Full Publication]

O'Neel, S. R., K. A. Echelmeyer, and R. J. Motyka. 2001. Short-term flow dynamics of a retreating tidewater glacier: LeConte Glacier, Alaska, USA. Journal of Glaciology 47(159):567-578. doi:10.3189/172756501781831855 [Details] [Full Publication]

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