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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

Significant Recent Publications

Timm, K., O'Neel, S., Hood, E., and Bidlack, A. (2014). From icefield to ocean explore the many ways that glaciers influence Alaska's coastal ecosystems. Retrieved April 9, 2014 from the Alaska Climate Science Center Web site: [pdf file 4.5 mb]

O’Neel, S., E. Hood, A. Arendt, and L. Sass (2014), Assessing streamflow sensitivity to variations in glacier mass balance, Climatic Change, 123(2):329-341. doi: 10.1007/s10584-013-1042-7.

Heeszel, D. S., H. A. Fricker, J. N. Bassis, S. O’Neel, and F. Walter (2014), Seismicity within a propagating ice shelf rift: The relationship between icequake locations and ice shelf structure, J. Geophys. Res. Earth Surf., doi: 10.1002/2013JF002849.

Arendt, A., S. Luthcke, A. Gardner, S. 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.

Bartholomaus, T. C., Larsen, C. F., and O'Neel, S., 2013, Does calving matter? Evidence for significant submarine melt: Earth and Planetary Science Letters, v. 380, p. 21–30.

Ethan Z. Welty, Timothy C. Bartholomaus, Shad O'Neel, W. Tad Pfeffer, (2013), Cameras as clocks, J. Glaciol. 59(214),275–286. [pdf file 627 kb]

Bartholomaus, T. C., C. F. Larsen, S. O'Neel, and M. E. West (2012), Calving seismicity from iceberg-sea surface interactions, J. Geophys. Res. F Earth Surf., 117(4), doi:10.1029/2012JF002513.

McNabb, R. W., R. Hock, S. O'Neel, L.A. Rasmussen, Y. Ahn, M. Braun, H. Conway, S. Herried, I. Joughin, W.T. Pfeffer, B.E. Smith, and M. Truffer. 2012. Using surface velocities to calculate bed topography: A case study at Columbia Glacier, Alaska, USA. J. Glaciology, 58(212):1151-1164. doi: 10.3189/2012JoG11J249

Pettit, E. C., J. A. Nystuen, and S. O'Neel. 2012. Listening to glaciers: Passive hydroacoustics near marine-terminating glaciers. Oceanography 25(3):104–105. doi: 10.5670/oceanog.2012.81 [pdf file 1.0 mb]

Walter, F., J. M. Amundson, M. Jason, S. 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 J. Geophys. Res., 117, F1, F01036, 11 pp. doi: 10.1029/2011JF002132

O'Neel, S. 2012. Surface mass balance of Columbia Glacier, Alaska, 1978 and 2010 balance years. U.S. Geological Survey Data Series 676, 8 p.

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

Post, A., S. O'Neel, R. J. Motyka and G. Streveler. 2011. A complex relationship between calving glaciers and climate, EOS, 92(37):305. doi: 10.1029/2011EO370001.

March, R. S. and S. O'Neel. 2011. Gulkana Glacier, Alaska—Mass balance, meteorology, and water measurements, 1997–2001: U.S. Geological Survey Scientific Investigations Report 2011-5046, 72 p.

O'Neel, S., 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, J. Geophys. Res., 115, F04034. doi:10.1029/2009JF001598.

Van Beusekom, A. E., S. 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. U.S. Geological Survey Scientific Investigations Report 2010–5247, 16 p.

Walter, F. S. O'Neel, D. 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

West, M. E., M. Truffer, S. O'Neel, C. Larsen, and L. LeBlanc. 2010. Glacier microseismicity, Geology, 30(4):319-322. doi: 10.1130/G30606.1.

Brunt, K. M., H. A. Fricker, L. Padman, T. A. Scambos, S. O'Neel. 2010. Mapping the grounding line of the Ross Ice Shelf, Antarctica, using ICESat laser altimetry, Ann. Glaciol., 51(55):71-79. doi:10.3189/172756410791392790.

Josberger, E. G., W. R. Bidlake, R. S. March, and S. O'Neel. 2009. Fifty-Year Record of Glacier Change Reveals Shifting Climate in the Pacific Northwest and Alaska, USA: U.S. Geological Survey Fact Sheet 2009-3046, 4 p.

Pfeffer, W. T., J. T. Harper, S. O'Neel. 2008. Kinematic constraints on glacier and land ice contributions to 21st century sea level rise, Science 321(5894):1340-1343. DOI: 10.1126/science.1159099.

O'Neel S. and W. T. Pfeffer. 2007. Source mechanics for monochromatic icequakes produced during iceberg calving at Columbia Glacier, AK, Geophys. Res. Lttrs., 34:L22502, 5 p. doi: 10.1029/2007GL031370

M. F. Meier, M. B. Dyurgerov, U. K. Rick, S. 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.

O'Neel S., H. P. Marshall, D. E. McNamara and W. T. Pfeffer. 2007. Detection and analysis of icequakes at Columbia Glacier, AK, Jour. Geophys. Res. 112, F02S13. doi: 10.1029/2006JF000595.

Harper, J. T., N. F. Humphrey, W. T. Pfeffer, T. Fudge and S. O'Neel. 2005. Evolution of subglacial water pressure along a glacier's length, Ann. Glaciol., 40, 31-36.

O'Neel S., W. T. Pfeffer, R. M. Krimmel and M. F. Meier. 2005, Evolving force balance at Columbia Glacier, during its rapid retreat, Jour. Geophys. Res., 110, F03012. doi: 10.1029/2005JF000292.

Anderson, R. S., S. P. Anderson, K. R. MacGregor, S. O'Neel, C. A. Riihimaki, E. D. Waddington and M. G. Loso. 2004. Strong feedbacks between hydrology and sliding of a small alpine glacier, Jour. Geophys. Res., 109, F03005. doi:10.1029/2004JF000120

O'Neel, S., K. A. Echelmeyer and R. J. Motyka. 2003. Short-term variations in calving of a tidewater glacier: LeConte Glacier, Alaska. J. Glaciol., 49(167):587-598.

Motyka R. J., S. 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.

O'Neel S., K. A. Echelmeyer and R. J. Motyka. 2001. Short-term flow dynamics of a retreating tidewater glacier: LeConte Glacier, Alaska, USA J. Glaciol. 47(159): 567-578.

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