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Martin Sharp and Libo Wang

1. Introduction Since the early 1990s there has been a sharp increase in the rate of global sea level rise, from a post-1961 average of 1.8 ± 0.5 mm yr −1 to a post 1993 average of 3.1 ± 0.7 mm yr −1 ( Solomon et al. 2007 ). Recent estimates suggest that ocean warming accounts for about 1.6 ± 0.5 mm yr −1 of the post-1993 rate, and that wastage of small glaciers and ice caps accounts for about 60% of the remainder ( Meier et al. 2007 ). The rate of glacier and ice cap wastage has increased

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Shawn J. Marshall and Martin J. Sharp

field descends to sea level on the east coast of Ellesmere Island and it terminates terrestrially on its western margin, at altitudes of 400 to 650 m. This asymmetry is due to a strong east–west gradient in the ice field’s snow accumulation regime, with southeasterly storm tracks from Baffin Bay providing the primary source of moisture for the ice field ( Koerner 1979 ). The observational network consists of two east–west lines crossing the ice field, one in the north (the NPOW line) and one in the

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Garry K. C. Clarke, Andrew B. G. Bush, and John W. M. Bush

.g., Thomas et al. 2007 ) and spatial heterogeneity of the terrestrial signal ( Seppä et al. 2007 ). For recent reviews see Alley and Ágústsdóttir (2005) and Rohling and Pälike (2005) . The cause of the 8.2 ka event remains controversial. A leading explanation is that the convective overturning of the North Atlantic Ocean was affected by the flux of freshwater to the Labrador Sea from the catastrophic drainage of an ice-dammed superlake that formed by the coalescence of glacial lakes Agassiz and

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Marc d’Orgeville and W. Richard Peltier

employed in this study is the CCSM3. The model has four interacting components—atmosphere, ocean, sea ice, and land surface—linked via a flux coupler. All of the simulations discussed in the following have been performed at T31 resolution for the atmospheric component (26 vertical levels and 3.75° horizontal resolution) and with a grid termed gx3v5 for the oceanic component (25 vertical levels, 3.6° resolution in the zonal direction, and variable in the meridional direction with approximately 0

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Guido Vettoretti, Marc d’Orgeville, William R. Peltier, and Marek Stastna

, meltwater generated by the retreat of the Laurentide ice sheet was being routed from glacial Lake Agassiz through the Mississippi River system into the Gulf of Mexico. At the onset of the YD, however, this route to the sea was abandoned when continental drainage is hypothesized to have switched to the east through the St. Lawrence River system to the Atlantic. Given the inability to identify the spillway that the eastward flow of meltwater would have occupied ( Lowell et al. 2005 ), it has been

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Marc d’Orgeville and W. Richard Peltier

long-time-scale simulations, that the SST variability in the North Atlantic was linked to the variability of the meridional overturning circulation (MOC; Delworth et al. 1993 ). In global warming experiments, on the other hand, it has been previously demonstrated that the amplitude of the reduction of the MOC in response to greenhouse gas–induced warming of the lowest atmosphere is a function of the mean climate from which warming ensues, essentially because of the impact upon sea ice coverage in

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Michael S. Pritchard, Andrew B. G. Bush, and Shawn J. Marshall

horizontal resolution limited by rhomboidal truncation at zonal wavenumber 30, whereas the oceanic component has 15 variably spaced vertical levels with a horizontal resolution of 2° latitude and 3.62° longitude. Oceanic vertical mixing is parameterized using the Richardson number scheme of Pacanowski and Philander (1981) and sea ice is modeled after Fanning and Weaver (1996) . Carbon dioxide is set to 200 ppm, and reconstructed ice sheet topography is from Peltier (1994) . The land surface albedo is

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Garry K. C. Clarke, Etienne Berthier, Christian G. Schoof, and Alexander H. Jarosch

1. Introduction The sea level equivalent volumes of the Greenland and Antarctic ice sheets are 7.3 and 56.6 m, respectively, whereas the combined volume of glaciers and small ice caps is far less. Yet, over the next 100 yr their 0.15–0.37-m contribution to sea level rise ( Lemke et al. 2007 ) is expected to dominate that from shrinkage of the great ice sheets (e.g., Ohmura 2004 ; Meier et al. 2007 ). Despite such compelling reasons to be interested in the volumes of glaciers and ice caps

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Stephen D. Griffiths and W. Richard Peltier

dissipation were considerably higher at LGM than at present ( Egbert et al. 2004 ; Uehara et al. 2006 ). On a smaller scale, past variations in tidal amplitudes may have local significance. At high latitudes, recent attention has been focused on amplification of semidiurnal tides under glacial conditions in the Labrador Sea ( Arbic et al. 2004b , 2008 ) and the Arctic Ocean ( Griffiths and Peltier 2008 ), and how these large tides might have interacted with adjoining ice streams and shelves to cause

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Alex S. Gardner, Martin J. Sharp, Roy M. Koerner, Claude Labine, Sarah Boon, Shawn J. Marshall, David O. Burgess, and David Lewis

1. Introduction Mass loss from glaciers and ice caps is likely the second largest contribution to global sea level rise after ocean thermal expansion ( Meier et al. 2007 ). Quantifying past contributions from this source is challenging because of the limited availability of measurements of glacier surface mass balance and rates of iceberg calving. Glacier surface mass balance models are widely used to compensate for this lack of measurements and can be used to predict how climate change will

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