High-resolution barotropic modeling and the calving of the Mertz Glacier, East Antarctica

ISI Document Delivery No.: 257JQ Times Cited: 1 Cited Reference Count: 22 Cited References: Andersen O. B., 1995, J GEOPHYS RES, V100, P282 Beaman RJ, 2011, ANTARCT SCI, V23, P95, DOI 10.1017/S095410201000074X Carrere L, 2003, GEOPHYS RES LETT, V30, DOI 10.1029/2002GL016473 DOMACK EW, 1982, BOREAS, V11, P79 Egbert GD, 2002, J ATMOS OCEAN TECH, V19, P183, DOI 10.1175/1520-0426(2002)019<0183:EIMOBO>2.0.CO;2 Keghouche I, 2009, J ATMOS OCEAN TECH, V26, P2216, DOI 10.1175/2009JTECHO678.1 KEYS HJR, 1990, ANTARCT SCI, V2, P243 Lacarra M., 2011, POLAR SCI, V5, P88, DOI [10.1016/j.polar.2011.04.008, DOI 10.1016/J.POLAR.2011.04.008] Le Bars Y, 2010, OCEAN MODEL, V31, P132, DOI 10.1016/j.ocemod.2009.11.001 Legresy B, 2004, J GLACIOL, V50, P427, DOI 10.3189/172756504781829828 Le Provost C, 1998, J GEOPHYS RES-OCEANS, V103, P5513, DOI 10.1029/97JC01733 Lescarmontier L., 2012, THESIS U P SABATIER Lescarmontier L, 2012, J GLACIOL, V58, P665, DOI 10.3189/2012JoG11J089 Lorenzin G., 2003, TECHNICAL REPORT Lyard F, 2006, OCEAN DYNAM, V56, P394, DOI 10.1007/s10236-006-0086-x LYNCH DR, 1979, COMPUT FLUIDS, V7, P207, DOI 10.1016/0045-7930(79)90037-9 Massom RA, 2010, J GEOPHYS RES-OCEANS, V115, DOI 10.1029/2009JC006083 Padman L, 2002, ANN GLACIOL, V34, P247, DOI 10.3189/172756402781817752 Pairaud IL, 2008, CONT SHELF RES, V28, P1294, DOI 10.1016/j.csr.2008.03.004 Potzsch A., 2000, ERS ENVISAT S LOOK E Ray R. D., 1999, 209478 GODD SPAC FLI Robertson R, 2005, ANTARCT SCI, V17, P107, DOI 10.1017/S0954102005002506 Mayet, C. Testut, L. Legresy, B. Lescarmontier, L. Lyard, F. CNES; ANR DACOTA grant; IPEV; CNRS/INSU; University Paul Sabatier Toulouse; ACE-CRC, University of Tasmania This study is part of the CRACICE project, supported by the CNES, ANR DACOTA grant, IPEV, CNRS/INSU, University Paul Sabatier Toulouse, and the ACE-CRC, University of Tasmania. We thank Rosemary Morrow from LEGOS for helpful reading and comments on the manuscript. We thank Ben Galton-Fenzi and Rob Massom from ACE-CRC, Hobart. They provided appreciated helpful discussions on the work and English language corrections. We thank Marie-Noelle Houssais from LOCEAN, Paris and leading the ALBION oceanographic program for providing the ADCP mooring pressure data. The SPOT images used in this study were obtained within the ISIS-CNES CRACICE project. The ENVISAT-ASAR images were obtained from the ESA AOPOL4096 project. The MODIS images were obtained through the NASA-EOSDIS website. 1 AMER GEOPHYSICAL UNION WASHINGTON J GEOPHYS RES-OCEANSIn February 2010, the Mertz Glacier Tongue (MGT) calved, releasing an 80 x 40 km iceberg. We have developed a high-resolution barotropic ocean model of the region to simulate the local circulation in response to tides and atmospheric forcing. We improved the coastline, grounding line position and built a new bathymetry using satellite imagery and older bathymetry data to derive the best available tidal model for the region. We compared this and other available models to seven different sea level observations available in the area and significantly improved the tidal solutions reaching a root sum square of 2.3 cm. This model was then run in different bathymetric configurations, considering the ice draft of the major icebergs B9B and C28, to simulate the circulation before, during, and after the calving event. The currents changed substantially in the neighborhood of the MGT and icebergs. The barotropic model with tidal and atmospheric forcing and the atmospheric wind fields allow us to evaluate the forces acting on the MGT. The sea surface slope force dominates the budget. Calving occurred when high tide and strong nontidal currents (due to atmospheric forcing) combined to lead to the monthly maximum forces exerted on the MGT (i.e., between 10 and 13 February 2010). While the forces are not unusually large at the calving time, the currents are largely enhanced in the rifting area. Therefore, processes related to these currents, like melting the ice melange inside the rifts, should be investigated to fully explain the final stage of the calving