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Modeling North American Freshwater Runoff through the Last Glacial Cycle

  • Shawn J. Marshall (a1) and Garry K.C. Clarke (a1)

The Northern Hemisphere ice sheets decayed rapidly during deglacial phases of the ice-age cycle, producing meltwater fluxes that may have been of sufficient magnitude to perturb oceanic circulation. The continental record of ice-sheet history is more obscured during the growth and advance of the last great ice sheets, ca. 120,000–20,000 yr B.P., but ice cores tell of high-amplitude, millennial-scale climate fluctuations that prevailed throughout this period. These climatic excursions would have provoked significant fluctuation of ice-sheet margins and runoff variability whenever ice sheets extended to mid-latitudes, giving a complex pattern of freshwater delivery to the oceans. A model of continental surface hydrology is coupled with an ice-dynamics model simulating the last glacial cycle in North America. Meltwater discharged from ice sheets is either channeled down continental drainage pathways or stored temporarily in large systems of proglacial lakes that border the retreating ice-sheet margin. The coupled treatment provides quantitative estimates of the spatial and temporal patterns of freshwater flux to the continental margins. Results imply an intensified surface hydrological environment when ice sheets are present, despite a net decrease in precipitation during glacial periods. Diminished continental evaporation and high levels of meltwater production combine to give mid-latitude runoff values that are highly variable through the glacial cycle, but are two to three times in excess of modern river fluxes; drainage to the North Atlantic via the St. Lawrence, Hudson, and Mississippi River catchments averages 0.356 Sv for the period 60,000–10,000 yr B.P., compared to 0.122 Sv for the past 10,000 yr. High-amplitude meltwater pulses to the Gulf of Mexico, North Atlantic, and North Pacific occur throughout the glacial period, with ice-sheet geometry controlling intricate patterns of freshwater routing variability. Runoff from North America is staged in the final deglaciation, with a stepped sequence of pulses through the Mississippi, St. Lawrence, Arctic, and Hudson Strait drainages.

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R.B. Alley (1991). Deforming-bed origin for southern Laurentide till sheets?. Journal of Glaciology. 37, 6776.

E. Bard , F. Rostek , C. Sonzogni (1997). Interhemispheric synchrony of the last deglaciation inferred from alkenone palaeothermoometry. Nature. 385, 707710.

D. B Blackwell and J. L. Steele (1992). Geothermal Map of North America. Decade of North American Geology, Map 006, Geological Society of America, Boulder, CO.

T. Blunier , J. Chappellaz , J. Schwander , A. Dällenbach , B. Stauffer , T.F. Stocker , D. Raynaud , J. Jouzel , H.B. Clausen , S.J. Johnsen (1998). Asynchrony of Antarctic and Greenland climate change during the last glacial period. Nature. 394, 739743.

G.S. Boulton , A.S. Jones (1979). Stability of temperate ice caps and ice sheets resting on beds of deformable sediment. Journal of Glaciology. 24, 2942.

G.S. Boulton , G.D. Smith , A.S. Jones , J. Newsome (1985). Glacial geology and glaciology of the last mid-latitude ice sheets. Geological Society of London Journal. 142, 447474.

E.A. Boyle , L.D. Keigwin (1982). Deep circulation of the North-Atlantic over the last 20 000 year: Geochemical evidence. Science. 218, 784786.

E.A. Boyle , L.D. Keigwin (1987). North-Atlantic thermohaline circulation during the past 20,000 year linked to high-latitude surface temperature. Nature. 330, 3540.

R. Braithwaite (1995). Positive degree-day factors for ablation on the Greenland ice sheet studied by energy-balance modelling. Journal of Glaciology. 41, 153160.

W.S. Broecker , D. Peteet , D. Rind (1985). Does the ocean-atmosphere system have more than one stable mode of operation?. Nature. 315, 2125.

W.S. Broecker , G. Bond , M. Klas , G. Bonani , W. Wolfli (1990). A salt oscillator in the glacial Atlantic? 1. The concept. Paleoceanography. 5, 469477.

P.U. Clark (1994). Unstable behaviour of the Laurentide Ice Sheet over deforming sediment and its implications for climate change. Quaternary Research. 41, 1925.

P.U. Clark , J.M. Licciardi , D.R. MacAyeal , J.W. Jenson (1996). Numerical reconstruction of a soft-bedded Laurentide Ice Sheet during the Last Glacial Maximum. Geology. 24, 679682.

P.U. Clark , R.B. Alley , L.D. Keigwin , J.M. Licciardi , S.J. Johnsen , H. Wang (1996). Origin of the first global meltwater pulse following the last glacial maximum. Paleoceanography. 11, 563577.

L. Clayton , J.T. Teller , J.W. Attig (1985). Surging of the southwestern part of the Laurentide Ice Sheet. Boreas. 14, 235241.

M.T. Coe (1998). A linked global model of terrestrial hydrologic processes: Simulation of modern rivers, lakes, and wetlands. Journal of Geophysical Research. 103, 88858899.

W. Dansgaard , S.J. Johnsen , H.B. Clausen , D. Dahl-Jensen , N. Gundestrup , C.U. Hammer , H. Oeschger (1984). North Atlantic climatic oscillations revealed by deep Greenland ice cores. In Climate Processes and Climate Sensitivity. J.E. Hansen , T. Takahashi Geophysical Monograph Series 29. pp. 288298. American Geophysical Union, Washington, DC.

W. Dansgaard (1993). Evidence for general instability of past climate from a 250-kyr ice-core record. Nature. 364, 218220.

G. Deblonde , W.R. Peltier (1993). Pleistocene Ice Age scenarios based upon observational evidence. Journal of Climate. 6, 709727.

J.A. Dowdeswell , M.A. Maslin , J.T. Andrews , I.N. McCave (1995). Iceberg production, debris rafting, and the extent and thickness of “Heinrich layers” (H-1, H-2) in North Atlantic sediments. Geology. 23, 301304.

A.S. Dyke , V.K. Prest (1987). Late Wisconsinan and Holocene history of the Laurentide Ice Sheet. Géographie physique et Quaternaire. 41, 237264.

R.G. Fairbanks (1989). A 17,000-year glacio-eustatic sea level record: Influence of glacial melting rates on the Younger Dryas event and deep-ocean circulation. Nature. 342, 637642.

A. Fanning , A.J. Weaver (1997). Temporal-geographical meltwater influences on the North Atlantic conveyor: Implications for the Younger Dryas. Paleoceanography. 12, 307320.

P.J. Fawcett , A.M. Agustsdottir , R.B. Alley , C.A. Shuman (1997). The Younger Dryas termination and North Atlantic deep water formation: Insights from climate model simulations and Greenland ice cores. Paleoceanography. 12, 2338.

D.A. Fisher , N. Reeh , K. Langley (1985). Objective reconstructions of the late Wisconsinan Laurentide Ice Sheet and the significance of deformable beds. Géographie physique et Quaternaire. 39, 229238.

S.W. Hostetler , F. Giorgi , G.T. Bates , P.J. Bartlein (1994). Lake-atmosphere feedbacks associated with paleolakes Bonneville and Lahontan. Science. 263, 665668.

S.W. Hostetler , P.U. Clark , P.J. Bartlein , A.C. Mix , N.J. Pisias (1999). Atmospheric transmission of North Atlantic Heinrich events. Journal of Geophysical Research. 104, 39473952.

P. Huybrechts (1990). A 3-D model for the Antarctic Ice Sheet: A sensitivity study on the glacial–interglacial contrast. Climate Dynamics. 5, 7992.

P. Huybrechts (1990). The Antarctic Ice Sheet during the last glacial–interglacial cycle: A three-dimensional experiment. Annals of Glaciology. 14, 115119.

P. Huybrechts , S. T'Siobbel (1995). Thermomechanical modelling of northern hemisphere ice sheets with a two-level mass-balance parameterisation. Annals of Glaciology. 21, 111117.

J.W. Jenson , D.R. MacAyeal , P.U. Clark , C.L. Ho , J.C. Vela (1996). Numerical modeling of subglacial sediment deformation: Implications for the behavior of the Lake Michigan Lobe, Laurentide Ice Sheet. Journal of Geophysical Research. 101, 87178728.

D. Jenssen (1977). A three-dimensional polar ice sheet model. Journal of Glaciology. 18, 373389.

E. Kalnay (1996). The NCEP/NCAR 40-year reanalysis project. Bulletin of the American Meteorological Society. 77, 437471.

L.D. Keigwin , G.A. Jones , S.J. Lehman , E.A. Boyle (1991). Deglacial meltwater discharge, North Atlantic deep circulation, and abrupt climate change. Journal of Geophysical Research. 96, 16,81116,826.

J. Kutzbach , R. Gallimore , S. Harrison , P. Behling , R. Selin , A. Laarif (1998). Climate and biome simulations for the past 21,000 year. Quaternary Science Reviews. 17, 473506.

D.R. Legates , C.J. Willmott (1990). Mean seasonal and spatial variability in gauge-corrected global precipitation. International Journal of Climate. 10, 111127.

M.W. Mahaffy (1976). A three-dimensional numerical model of ice sheets: Tests on the Barnes Ice Cap, Northwest Territories. Journal of Geophysical Research. 81, 10591066.

S. Manabe , R.J. Stouffer (1995). Simulation of abrupt climate change induced by freshwater input to the North Atlantic ocean. Nature. 378, 165167.

S. Manabe , R.J. Stouffer (1997). Coupled ocean–atmosphere model response to freshwater input: Comparison to Younger Dryas event. Paleoceanography. 12, 321336.

S.J. Marshall , G.K.C. Clarke (1997). A continuum mixture model of ice stream thermomechanics in the Laurentide Ice Sheet 1. Theory. Journal of Geophysical Research. 102, .

S.J. Marshall , G.K.C. Clarke (1997). A continuum mixture model of ice stream thermomechanics in the Laurentide Ice Sheet 2. Application to the Hudson Strait Ice Stream. Journal of Geophysical Research. 102, 20,61520,638.

H. Oeschger , J. Beer , U. Siegenthaler , B. Stauffer , W. Dansgaard , C.C. Langway (1984). Late glacial climate history derived from ice cores. J.E. Hansen , T. Takahashi Climate Processes and Climate Sensitivity. Geophysical Monograph Series 29. American Geophysical Union, Washington., 299306.

W.R. Peltier (1994). Ice age paleotopography. Science. 265, 195201.

D. Pollard (1983). A coupled climate–ice sheet model applied to the Quaternary ice ages. Journal of Geophysical Research. 88, 77057718.

S. Rahmstorf (1995). Bifurcations of the Atlantic thermohaline circulation in response to changes in the hydrological cycle. Nature. 378, 145149.

C. Ritz , A. Fabre , A. Letréguilly (1997). Sensitivity of a Greenland ice sheet model to ice flow and ablation parameters: Consequences for evolution through the last climatic cycle. Climate Dynamics. 13, 1124.

T.F. Stocker (1998). The seesaw effect. Science. 282, 6162.

T.F. Stocker , D.G. Wright (1991). Rapid transitions of the ocean's deep circulation induced by changes in surface water fluxes. Nature. 351, 729732.

M. Stuiver , P.J. Reimer , E. Bard , J.W. Beck , G.S. Burr , K.A. Hughen , B. Kromer , F.G. McCormac , J. Van der Plicht , M. Spurk (1998). INTCAL98 radiocarbon age calibration, 24,000–0 cal B.P. Radiocarbon. 40, 10411083.

L. Tarasov , W.R. Peltier (1997). A high-resolution model of the 100-kyr ice-age cycle. Annals of Glaciology. 25, 5865.

L. Tarasov , W.R. Peltier (1999). The impact of thermo-mechanical ice sheet coupling on a model of the 100 kyr ice-age cycle. Journal of Geophysical Research. 104, 95179545.

J.T. Teller (1995). History and drainage of large ice-dammed lakes along the Laurentide Ice Sheet. Quaternary International. 28, 8392.

J.T. Teller , A.E. Kehew (1994). Introduction to the late glacial history of large proglacial lakes and meltwater runoff along the Laurentide Ice Sheet. Quaternary Science Reviews. 13, 795799.

A.J. Weaver , J. Marotzke , P.F. Cummins , E.S. Sarachik (1993). Stability and variability of the thermohaline circulation. Journal of Physical Oceanography. 23, 3960.

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