| Title | North American Ice Sheet reconstructions at the Last Glacial Maximum |
| Author | Marshall, S J; James, T S; Clarke, G K C |
| Source | Quaternary Science Reviews vol. 21, issues 1-3, 2002 p. 175-192, https://doi.org/10.1016/s0277-3791(01)00089-0 |
| Year | 2002 |
| Alt Series | Geological Survey of Canada, Contribution Series 2001087 |
| Publisher | Elsevier BV |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut |
| NTS | 1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560 |
| Lat/Long WENS | -141.0000 -50.0000 90.0000 41.7500 |
| Subjects | environmental geology; ice sheets; glaciology; ice thicknesses; ice; ice thickness; paleoclimatology; sea level changes; climatology |
| Illustrations | tables; formulae; graphs; bar graphs; location maps |
| Abstract | The areal extent of the last glacial maximum (LGM) ice sheets is well known in North America, but there is no direct geological proxy for ice sheet thickness or volume. Uncertainties associated with
glaciological and geophysical reconstructions give widely varying estimates of North American Ice Sheet (NAIS) volume at LGM. In an effort to quantify the uncertainty associated with glaciological reconstructions, we conducted a suite of 190
numerical simulations of the last glacial cycle in North America, prescribing different climatic, mass balance, glaciologic, and isostatic treatments for the least constrained model variables. LGM ice sheet reconstructions were evaluated using the
well-established geologic record of ice sheet area and southern extent at LGM (Dyke and Prest (1987)). These constraints give a subset of 33 simulations that produce reasonable LGM ice cover in North America. Ice sheet dispositions and the associated
parameter settings in this subset of tests provide insight into the plausible range of NAIS thickness, form, and mass balance regime at LGM. Ice volume in this subset of tests spans a range of 28.5-38.9×10exp15 m3 at LGM, with a predominant cluster
at 32-36×10exp15 m3. Taking floating ice and displaced continental water into account, this corresponds to 69-94 m eustatic sea level (msl). More than 75% of the accepted tests fall in the range 78-88 msl. We argue that this is a plausible estimate
of the volume of water locked up in the NAIS at LGM. |
| GEOSCAN ID | 212817 |
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