Oceanography The Official Magazine of
The Oceanography Society
Volume 29 Issue 04

View Issue TOC
Volume 29, No. 4
Pages 34 - 45

OpenAccess

Connecting the Greenland Ice Sheet and the Ocean: A Case Study of Helheim Glacier and Sermilik Fjord

By Fiammetta Straneo , Gordon S. Hamilton, Leigh A. Stearns , and David A. Sutherland 
Jump to
Article Abstract Citation References Copyright & Usage
Article Abstract

The rapid ice loss from the Greenland Ice Sheet that began in the late 1990s sparked an interest in glacier/ocean exchanges both because an increase in submarine melting of the glacier is a potential trigger of glacier retreat and because the increasing freshwater discharge can affect the regional ocean’s circulation and ecosystems. An interdisciplinary field project focused on the Helheim Glacier-Sermilik Fjord system began in 2008 and has continued to date. We found that warm, Atlantic Water flows into the fjord, drives melting of the glacier, and is regularly replenished through shelf-forced and glacier-driven circulations. In summer, the release of surface melt at the base of the glacier has a pronounced impact on local ocean circulation, the properties of the glacier, and its melt rate. Measurements taken in the fjord indicate that it is virtually impossible to derive submarine melt rates from hydrographic (including moored) data due to the fjord’s pronounced water mass variability and uncertain contribution from iceberg melt. Efforts to correlate glacier behavior with ocean forcing on seasonal and interannual time scales yield no straightforward connections, likely because of a dependence on a wider range of parameters, including subglacial discharge and bedrock geometry. This project emphasizes the need for sustained long-term measurements of multiple glacier/ocean/atmosphere systems to understand the different dynamics that control their evolution. 

Citation

Straneo, F., G.S. Hamilton, L.A. Stearns, and D.A. Sutherland. 2016. Connecting the Greenland Ice Sheet and the ocean: A case study of Helheim Glacier and Sermilik Fjord. Oceanography 29(4):34–45, https://doi.org/10.5670/oceanog.2016.97.

References

Amundson, J.M., M. Fahnestock, M. Truffer, J. Brown, M.P. Lüthi, and R.J. Motyka. 2010. Ice mélange dynamics and implications for terminus stability, Jakobshavn Isbræ, Greenland. Journal of Geophysical Research 115, F01005, https://doi.org/10.1029/2009JF001405.

Andres, M., A. Silvano, F. Straneo, and D.R Watts. 2015. Icebergs and sea ice detected with inverted echo sounders. Journal of Atmospheric and Oceanic Technology 32(5):1,042–1,057, https://doi.org/10.1175/JTECH-D-14-00161.1.

Bamber, J., M. van den Broeke, J. Ettema, J. Lenaerts, and E. Rignot. 2012. Recent large increases in freshwater fluxes from Greenland into the North Atlantic. Geophysical Research Letters 39, L19501, https://doi.org/10.1029/2012GL052552

Beaird, N., F. Straneo, and W. Jenkins. 2015. Spreading of Greenland meltwaters in the ocean revealed by noble gases. Geophysical Research Letters 42(18):7,705–7,713, https://doi.org/10.1002/2015GL065003.

Bersch, M., I. Yashayaev, and K.P. Koltermann. 2007. Recent changes of the thermohaline circulation in the subpolar North Atlantic. Ocean Dynamics 57:223–235, https://doi.org/10.1007/s10236-007-0104-7.

Boning, C.W., E. Behrens, A. Biastoch, K. Getzlaff, and J. Bamber. 2016. Emerging impact of Greenland meltwater on deepwater formation in the North Atlantic. Nature Geoscience 9:523–527, https://doi.org/10.1038/ngeo2740.

Burgess, E.W., R.R. Forster, J.E. Box, E. Mosley-Thompson, D.H. Bromwich, R.C. Bales, and L.C. Smith. 2010. A spatially calibrated model of annual accumulation rate on the Greenland Ice Sheet (1958–2007). Journal of Geophysical Research 115, F02004, https://doi.org/10.1029/2009JF001293.

Csatho, B.M., A.F. Schenk, C.J. van der Veen, G. Babonis, K. Duncan, S. Rezvanbehbahani, M.R. van den Broeke, S.B. Simonsen, S. Nagarajan, and J.H. van Angelen. 2014. Laser altimetry reveals complex pattern of Greenland Ice Sheet dynamics. Proceedings of the National Academy of Sciences of the United States of America 111(52):18,478–18,483, https://doi.org/10.1073/pnas.1411680112.

de Steur, L., E. Hansen, R. Gerdes, M. Karcher, E. Fahrbach, and J. Holfort. 2009. Freshwater fluxes in the East Greenland Current: A decade of observations. Geophysical Research Letters 36, L23611, https://doi.org/10.1029/2009GL041278.

de Jong, M.F., and L. de Steur. 2016. Strong winter cooling over the Irminger Sea in winter 2014–2015, exceptional deep convection, and the emergence of anomalously low SST. Geophysical Research Letters 46:7,106–7,113, https://doi.org/​10.1002/2016GL069596.

Dickson, R., B. Rudels, S. Dye, M. Karcher, J. Meincke, and I. Yashayaev. 2007. Current estimates of freshwater flux through Arctic and subarctic seas. Progress in Oceanography 73(3):210–230, https://doi.org/10.1016/j.pocean.2006.12.003.

Enderlin, E.M., and G.S. Hamilton. 2014. Estimates of iceberg submarine melting from high-​resolution digital elevation models: Application to Sermilik Fjord, East Greenland. Journal of Glaciology 60(224):1,084–1,092, https://doi.org/​10.3189/2014JoG14J085.

Enderlin, E.M., G.S Hamilton, F. Straneo, and D.A. Sutherland. In press. Iceberg meltwater fluxes dominate the freshwater budget in Greenland’s iceberg congested glacial fjords. Geophysical Research Letters. 

Enderlin, E.M., I.M. Howat, S. Jeong, M.J. Noh, J.H. Angelen, and M.R. Broeke. 2014. An improved mass budget for the Greenland ice sheet. Geophysical Research Letters 41(3):866–872, https://doi.org/10.1002/2013GL059010

Franco, B., X. Fettweis, and M. Erpicum. 2013. Future projections of the Greenland ice sheet energy balance driving the surface melt. The Cryosphere 7:1–18, https://doi.org/10.5194/tc-7-1-2013.

Gregory, J.M., and P. Huybrechts. 2006. Ice-sheet contributions to future sea-level change. Philosophical Transactions of the Royal Society A: Mathematical Physical and Engineering Sciences 364:1,709–1,731, https://doi.org/10.1098/rsta.2006.1796.

Haine, T.W.N., B. Curry, R. Gerdes, E. Hansen, M. Karcher, C. Lee, B. Rudels, G. Spreen, L. de Steur, K.D. Stewart, and R. Woodgate. 2015. Arctic freshwater export: Status, mechanisms, and prospects. Global and Planetary Change 125:13–35, https://doi.org/10.1016/​j.gloplacha.2014.11.013.

Hanna, E., S.H. Mernild, J. Cappelen, and K. Steffen. 2012. Recent warming in Greenland in a long-term instrumental (1881–2012) climatic context: Part I. Evaluation of surface air temperature records. Environmental Research Letters 7:045404, https://doi.org/10.1088/1748-9326/7/4/045404.

Harden, B.E., F. Straneo, and D.A. Sutherland. 2014. Moored observations of synoptic and seasonal variability in the East Greenland Coastal Current. Journal of Geophysical Research 119:8,838–8,857, https://doi.org/10.1002/2014JC010134.

Holland, D.M., and A. Jenkins. 1999. Modeling thermodynamic ice-ocean interactions at the base of an ice shelf. Journal of Physical Oceanography 29:1,787–1,800, https://doi.org/10.1175/1520-0485(1999)029​<1787:MTIOIA>2.0.CO;2.

Holland, D.M., R.H. Thomas, B. De Young, M.H. Ribergaard, and B. Lyberts. 2008. Acceleration of Jakboshavn Isbræ triggered by warm subsurface ocean waters. Nature Geoscience 1:659–664, https://doi.org/10.1038/ngeo316.

Howat, I. 2016. MEaSURES Greenland Ice Velocity: Selected Glacier Site Velocity Maps from Optical Images, Version 1. Boulder, CO, USA. NASA National Snow and Ice Data Center Distributed Active Archive Center, https://doi.org/10.5067/EYV1IP7MUNSV.

Howat, I.M., and A. Eddy. 2011. Multi-decadal retreat of Greenland’s marine-terminating glaciers. Journal of Glaciology 57(203):389–396.

Howat, I.M., I. Joughin, and T.A. Scambos. 2007. Rapid changes in ice discharge from Greenland outlet glaciers. Science 315:1,559–1,561, https://doi.org/10.1126/science.1138478.

Jackson, R.H., and F. Straneo. 2016. Heat, salt, and freshwater budgets for a glacial fjord in Greenland. Journal of Physical Oceanography, https://doi.org/10.1175/JPO-D-15-0134.1.

Jackson, R.H., F. Straneo, and D.A. Sutherland. 2014. Externally forced fluctuations in ocean temperature at Greenland glaciers in non-summer months. Nature Geoscience 7:503–508, https://doi.org/10.1038/ngeo2186

Jenkins, A. 1999. The impact of melting ice on ocean waters. Journal of Physical Oceanography 29:2,370–2,381, https://doi.org/​10.1175/1520-0485(1999)029​<2370:TIOMIO>2.0.CO;2.

Jenkins, A. 2011. Convection-driven melting near the grounding line of ice shelves and tidewater glaciers. Journal of Physical Oceanography 41:2,279–2,294, https://doi.org/10.1175/JPO-D-11-03.1.

Joughin, I., I. Howat, B. Smith, and T. Scambos. 2011 (updated 2016). MEaSUREs Greenland Ice Velocity: Selected Glacier Site Velocity Maps from InSAR, Version 1. (Subset E66.50N). Boulder, Colorado USA. NASA National Snow and Ice Data Center Distributed Active Archive Center, https://doi.org/10.5067/MEASURES/CRYOSPHERE/nsidc-0481.001

Moon, T., I. Joughin, B. Smith, and I. Howat. 2012. 21st-century evolution of Greenland outlet glacier velocities. Science 336:576–578, https://doi.org/10.1126/science.1219985.

Morlighem, M., E. Rignot, J. Mouginot, H. Seroussi, and E. Larour. 2014. Deeply incised submarine glacial valleys beneath the Greenland ice sheet. Nature Geoscience 7(6):418–422, https://doi.org/10.1038/ngeo2167.

Motyka, R.J., L. Hunter, K.A. Echelmeyer, and C. Connor. 2003. Submarine melting at the terminus of a temperate tidewater glacier, LeConte Glacier, Alaska, USA. Annals of Glaciology 36(1):57–65.

Motyka, R.J., M. Truffer, M. Fahnestock, J. Mortensen, S. Rysgaard, and I. Howat. 2011. Submarine melting of the 1985 Jakobshavn Isbræ floating tongue and the triggering of the current retreat. Journal of Geophysical Research 116, F01007, https://doi.org/10.1029/2009JF001632.

Murray, T., K. Scharrer, T.D. James, S.R. Dye, E. Hanna, A.D. Booth, N. Selmes, A. Luckman, A.L.C. Hughes, S. Cook, and P. Huybrechts. 2010. Ocean regulation hypothesis for glacier dynamics in southeast Greenland and implications for ice-sheet mass changes. Journal of Geophysical Research 115, F03026, https://doi.org/10.1029/2009JF001522.

Nettles, M., T. Larsen, P. Elósegui, G.S. Hamilton, L.A. Stearns, A. Ahlstrøm, J.L. Davis, M.L. Andersen, J. de Juan, S.A. Khan, and others. 2008. Step-wise changes in glacier flow speed coincide with calving and glacial earthquakes at Helheim Glacier, Greenland. Geophysical Research Letters 35, L24503, https://doi.org/10.1029/2008GL036127.

Noël, B., W. van de Berg, H. Machguth, S. Lhermitte, I. Howat, X. Fettweis, and M.R. van den Broeke. 2016. A daily, 1-km resolution dataset of downscaled Greenland ice sheet surface mass balance (1958–2015). The Cryosphere Discussions, https://doi.org/10.5194/tc-2016-145.

Oltmanns, M., F. Straneo, G.W.K. Moore, and S.H. Mernild. 2014. Strong downslope wind events in Ammassalik, southeast Greenland. Journal of Climate 27:977–992, https://doi.org/10.1175/JCLI-D-13-00067.1.

Ridley, J.K., P. Huybrechts, L.M. Gregory, and J.A. Lowe. 2005. Elimination of the Greenland Ice Sheet in a high CO2 climate. Journal of Climate 18(17):3,409–3,427, https://doi.org/10.1175/JCLI3482.1.

Rignot, E.J., and P. Kanagaratnam. 2006. Changes in the velocity structure of the Greenland Ice Sheet. Science 311:986–990, https://doi.org/10.1126/science.1121381.

Rignot, E., M. Koppes, and I. Velicogna. 2010. Rapid submarine melting of the calving faces of West Greenland glaciers. Nature Geoscience 3(3):187–191, https://doi.org/10.1038/ngeo765.

Rosenau, R., M. Scheinert, and R. Dietrich. 2015. A processing system to monitor Greenland outlet glacier velocity variations at decadal and seasonal time scales utilizing the Landsat imagery. Remote Sensing of the Environment 169:1–19, https://doi.org/10.1016/j.rse.2015.07.012.

Rudels, B., G. Björk, J. Nilsson, P. Winsor, I. Lake and C. Nohr. 2005. The interaction between waters from the Arctic Ocean and the Nordic Seas north of Fram Strait and along the East Greenland Current: Results from the Arctic Ocean–02 Oden Expedition. Journal of Marine Systems 55:1–30, https://doi.org/10.1016/j.jmarsys.2004.06.008.

Schild, K.M., and G.S. Hamilton. 2013. Seasonal variations in outlet glacier terminus positions in Greenland. Journal of Glaciology 59(216):759–770, https://doi.org/10.3189/2013JoG12J238.

Schjøth, F., C.S. Andresen, F. Straneo, T. Murray, K. Scharrer, and A. Korablev. 2012. Campaign to map the bathymetry of a major Greenland fjord. Eos, Transactions American Geophysical Union 93(14):141, https://doi.org/​10.1029/2012EO140001.

Sciascia, R., F. Straneo, C. Cenedese, and P. Heimbach. 2013. Seasonal variability of submarine melt rate and circulation in an East Greenland fjord. Journal of Geophysical Research 118:2,492–2,506, https://doi.org/​10.1002/jgrc.20142.

Shepherd, A., E.R. Ivins, A. Geruo, V.R. Barletta, M.J. Bentley, S. Bettadpur, and M. Horwath. 2012. A reconciled estimate of ice-sheet mass balance. Science 338:1,183–1,189, https://doi.org/10.1126/science.1228102.

Stearns, L.A., and G.S. Hamilton. 2007. Rapid volume loss from two East Greenland outlet glaciers quantified using repeat stereo satellite imagery. Geophysical Research Letters 34, L05503, https://doi.org/10.1029/2006GL028982.

Straneo, F., and C. Cenedese. 2015. The dynamics of Greenland’s glacial fjords and their role in climate. Annual Review of Marine Science 7:89–112, https://doi.org/​10.1146/annurev-marine-010213-135133.

Straneo, F., R.G. Curry, D.A Sutherland, G.S Hamilton, C. Cenedese, K. Vage, and L.A. Stearns. 2011. Impact of fjord dynamics and glacial runoff near Helheim Glacier. Nature Geoscience 4:332–327, https://doi.org/10.1038/NGEO1109.

Straneo, F., G.S. Hamilton, D.A. Sutherland, L.A. Stearns, F. Davidson, M.O. Hammill, G.B. Stenson, and A. Rosing-Asvid. 2010. Rapid circulation of warm subtropical waters in a major glacial fjord in East Greenland. Nature Geoscience 3:182–186, https://doi.org/10.1038/ngeo764.

Straneo, F., and P. Heimbach. 2013. North Atlantic warming and the retreat of Greenland’s outlet glaciers. Nature 504:36–43, https://doi.org/10.1038/nature12854

Straneo, F., P. Heimbach, O. Sergienko, G.S. Hamilton, G. Catania, S. Griffies, R. Hallberg, A. Jenkins, I. Joughin, R. Motyka, and others. 2013. Challenges to understanding the dynamic response of Greenland’s marine terminating glaciers to oceanic and atmospheric forcing. Bulletin of the American Meteorological Society 94:1,131–1,144, https://doi.org/10.1175/BAMS-D-12-00100.1.

Sutherland, D.A., and R.S. Pickart. 2008. The East Greenland Coastal Current: Structure, variability, and forcing. Progress in Oceanography 1:58–77, https://doi.org/10.1016/j.pocean.2007.09.006

Sutherland, D.A., G.E. Roth, G.S. Hamilton, S.H. Mernild, L.A. Stearns, and F. Straneo. 2014a. Quantifying flow regimes in a Greenland glacial fjord using iceberg drifters. Geophysical Research Letters 41:8,411–8,420, https://doi.org/10.1002/2014GL062256.

Sutherland, D.A., and F. Straneo. 2012. Estimating ocean heat transport and submarine melt rate in Sermilik Fjord, Greenland, using lowered ADCP profiles. Annals of Glaciology 53(60):50–58.

Sutherland, D.A., F. Straneo, and R.S. Pickart. 2014b. Characteristics and dynamics of two major Greenland glacial fjords. Journal of Geophysical Research 119:3,767–3,791, https://doi.org/10.1002/2013JC009786

Sutherland, D.A., F. Straneo, G.B. Stenson, F. Davidson, M.O. Hammill, and A. Rosing-Asvid. 2013. Atlantic water variability on the southeast Greenland shelf and its relationship to SST and bathymetry. Journal of Geophysical Research 118:847–855, https://doi.org/10.1029/2012JC008354.

Truffer, M., and R. Motyka. 2016. Where glaciers meet water: Subaqueous melt and its relevance to glaciers in various settings. Reviews of Geophysics 54:220–239, https://doi.org/​10.1002/2015RG000494.

Våge, K., R.S. Pickart, A. Sarafanov, Ø. Knutsen, H. Mercier, P. Lherminier, H.M. Van Aken, J. Meincke, D. Quadfasel, and S. Bacon. 2011. The Irminger Gyre: Circulation, convection, and interannual variability. Deep Sea Research Part I 58(5):590–614, https://doi.org/10.1016/​j.dsr.2011.03.001

Xu, Y., E. Rignot, I. Fenty, D. Menemenlis, and M. Mar Flexas. 2013. Subaqueous melting of Store Glacier, west Greenland, from three-dimensional, high-resolution numerical modeling and ocean observations. Geophysical Research Letters 40:4,648–4,653, https://doi.org/10.1002/grl.50825.

Copyright & Usage

This is an open access article made available under the terms of the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution, and reproduction in any medium or format as long as users cite the materials appropriately, provide a link to the Creative Commons license, and indicate the changes that were made to the original content. Images, animations, videos, or other third-party material used in articles are included in the Creative Commons license unless indicated otherwise in a credit line to the material. If the material is not included in the article’s Creative Commons license, users will need to obtain permission directly from the license holder to reproduce the material.