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Numerical modeling of the Snowmass Creek paleoglacier, Colorado, and climate in the Rocky Mountains during the Bull Lake glaciation (MIS 6)

Published online by Cambridge University Press:  20 January 2017

Eric M. Leonard*
Affiliation:
Department of Geology, Colorado College, Colorado Springs, CO 80903, USA
Mitchell A. Plummer
Affiliation:
Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-2107, USA
Paul E. Carrara
Affiliation:
U.S. Geological Survey, Denver Federal Center, Box 25046, MS-980, Denver, CO 80225, USA
*
Corresponding author.E-mail address:eleonard@coloradocollege.edu (E.M. Leonard).

Abstract

Well-preserved moraines from the penultimate, or Bull Lake, glaciation of Snowmass Creek Valley in the Elk Range of Colorado (USA) present an opportunity to examine the character of the high-altitude climate in the Rocky Mountains during Marine Oxygen Isotope Stage 6. This study employs a 2-D coupled mass/energy balance and flow model to assess the magnitudes of temperature and precipitation change that could have sustained the glacier in mass-balance equilibrium at its maximum extent during the Bull Lake glaciation. Variable substrate effects on glacier flow and ice thickness make the modeling somewhat more complex than in geologically simpler settings. Model results indicate that a temperature depression of about 6.7°C compared with the present (1971–2000 AD) would have been necessary to sustain the Snowmass Creek glacier in mass-balance equilibrium during the Bull Lake glaciation, assuming no change in precipitation amount or seasonality. A 50% increase or decrease from modern precipitation would have been coupled with 5.2°C and 9.1°C Bull Lake temperature depressions respectively. Uncertainty in these modeled temperature depressions is about 1°C.

Type
Articles
Copyright
University of Washington

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References

Anderson, R.S., Duhnforth, M., Colgan, W., and Anderson, L. Far-flung moraines: exploring the feedback of glacial erosion on the evolution of glacier length. Geomorphology 179, (2012). 269285.Google Scholar
Birkel, S.D., Putnam, A.E., Denton, G.H., Koons, P.O., Fastook, J.L., Putnam, D.E., and Maasch, K.A. Climate inferences from a glaciological reconstruction of the Late Pleistocene Wind River Ice Cap, Wind River Range, Wyoming. Arctic, Antarctic, and Alpine Research 44, (2012). 265276.CrossRefGoogle Scholar
Brugger, K.A. Late Pleistocene climate inferred from the reconstruction of the Taylor River glacier complex, southern Sawatch Range, Colorado. Geomorphology 75, (2006). 318329.CrossRefGoogle Scholar
Brugger, K.A. Climate in the southern Sawatch Range and Elk Mountains, Colorado, U.S.A., during the Last Glacial Maximum: inferences using a simple degree-day model. Arctic, Antarctic, and Alpine Research 42, (2010). 164178. http://dx.doi.org/10.1657/1938-4246-42.2.164 Google Scholar
Brugger, K.A., and Goldstein, B.S. Paleoglacier Reconstruction and Late-Pleistocene Equilibrium-Line Altitudes, Southern Sawatch Range, Colorado. Mickelson, D.M., and Attig, J.W. Glacial Processes Past and Present. Geological Society of America, Special Paper 337, (1999). 103112.Google Scholar
Bryant, B. (1969). Geologic map of the Maroon Bells quadrangle, Pitkin and Gunnison Counties, Colorado. U.S. Geological Survey, Geologic Quadrangle Map GQ-788, Scale 1:24,000. Google Scholar
Bryant, B. (1972). Geologic map of the Highland Peak quadrangle, Pitkin County, Colorado. U.S. Geological Survey, Geologic Quadrangle Map GQ-932, Scale 1:24,000.CrossRefGoogle Scholar
Clark, P.U., Dyke, A.S., Shakun, J.D., Carlson, A.E., Clark, J., Wohlfarth, B., Mitrovica, J.X., Hostetler, S.W., and McCabe, A.M. The last glacial maximum. Science 325, (2009). 710714.CrossRefGoogle ScholarPubMed
Cuffey, K.M., and Paterson, W.S.B. The Physics of Glaciers. 4th ed. (2010). Elsevier, Boston.Google Scholar
Elias, S.A. Late Pleistocene and Holocene seasonal temperatures reconstructed from fossil beetle assemblages in the Rocky Mountains. Quaternary Research 46, (1996). 311318.Google Scholar
Freeman, V.L. (1972). Geologic map of the Woody Creek quadrangle, Pitkin and Eagle Counties, Colorado. U.S. Geological Survey, Geologic Quadrangle Map GQ-967, Scale 1:24,000.Google Scholar
Garcia, R.V., Kelley, S.A., and Heitzler, M.T. Geo and thermochronology of Elk and West Elk Mountain Range plutons, Southwestern Colorado: temporal and spatial intrusion and exhumation variations. Geological Society of America Abstracts with Programs 42, (2010). 77 Google Scholar
Hutter, K. Theoretical Glaciology: Material Science of Ice and the Mechanics of Glaciers and Ice Sheets. (1983). Reidel, Dordrecht, Netherlands.Google Scholar
Jarosch, A.H., Schoof, C.G., and Anslow, F.S. Restoring mass conservation in shallow ice flow models over complex terrain. The Cryosphere 7, (2013). 229240.CrossRefGoogle Scholar
Laabs, B.J.C., Plummer, M.A., and Mickelson, D.M. Climate during the last glacial maximum in the Wasatch and southern Uinta Mountains inferred from glacier modeling. Geomorphology 75, (2006). 300317.Google Scholar
Le Meur, E., and Vincent, C. A two-dimensional shallow ice-flow model of glacier de Saint-Sorlin, France. Journal of Glaciology 49, (2003). 527538.Google Scholar
Le Meur, E., Gagliardini, O., Zwinger, T., and Ruokolainen, J. Glacier flow modelling: a comparison of the shallow ice approximation and the full-Stokes solution. Comptes Rendus Physique 5, (2004). 709722.Google Scholar
Leonard, E.M. Climatic change in the Colorado Rocky Mountains: estimates based on modern climate at late Pleistocene equilibrium lines. Arctic and Alpine Research 21, (1989). 245255.Google Scholar
Leonard, E.M. Modeled patterns of Late Pleistocene glacier inception and growth in the Southern and Central Rocky Mountains, USA: sensitivity to climate change and paleoclimatic implications. Quaternary Science Reviews 26, (2007). 21522166.Google Scholar
Leonard, E.M., Laabs, B.J.C., Plummer, M.A., Huss, E., Spiess, V.M., Mackall, B.T., Jacobsen, R.E., and Quirk, B. Climate Along the Crest of the US Rocky Mountains During the Last Glaciation: Preliminary Insights From Numerical Modeling of Paleoglaciers. American Geophysical Union 2012 Fall Meeting. Abstract (2012). 51A2106A.Google Scholar
Leysinger Vieli, G.J.-M.C., and Gudmundsson, G.H. On estimating length fluctuations of glaciers caused by changes in climatic forcing. Journal of Geophysical Research 109, (2004). F01007 http://dx.doi.org/10.1029/2003JF000027 Google Scholar
Lyle, M., Heusser, L., Ravelo, C., Yamamoto, M., Barron, J., Diffenbaugh, N.S., Herbert, T., and Andreasen, D. Out of the Tropics: the Pacific, Great Basin lakes, and Late Pleistocene water cycle in the Western United States. Science 337, (2012). 16291633.CrossRefGoogle ScholarPubMed
Mahan, S.A., Gray, H.J., Pigati, J.S., Wilson, J., Lifton, N.A., Paces, J.P., and Blaauw, M. A geochronologic framework for the Ziegler Reservoir fossil site, Snowmass Village, Colorado. Quaternary Research 82, (2014). 490503. (in this volume) CrossRefGoogle Scholar
Mumma, S.A., Whitlock, C., and Pierce, K. A 28,000 year history of vegetation and climate from Lower Red Rock Lake, Centennial Valley, southwestern Montana, USA. Palaeogeography, Palaeoclimatology, Palaeoecology 326–328, (2012). 3041.Google Scholar
Mutschler, F.E. (1970). Geologic map of the Snowmass Mountain quadrangle, Pitkin and Gunnison Counties, Colorado. U.S. Geological Survey, Geologic Quadrangle Map GQ-853, Scale 1:24,000.Google Scholar
Paterson, W.S.B. The Physics of Glaciers. 3rd ed. (1994). Pergamon, Oxford.Google Scholar
Pigati, J.S., Miller, I.M., Johnson, K.R., Honke, J.S., Carrara, P.E., Muhs, D.R., Skipp, G., and Bryant, B. Geologic setting and stratigraphy of the Ziegler Reservoir fossil site, Snowmass Village, Colorado. Quaternary Research 82, (2014). 477489. (in this volume) CrossRefGoogle Scholar
Plummer, M.A., and Phillips, F.M. A 2-D numerical model of snow/ice energy balance and ice flow for paleoclimatic interpretation of glacial geomorphic features. Quaternary Science Reviews 22, (2003). 13891406.Google Scholar
Porter, S.C. Equilibrium-line altitudes of late Quaternary glaciers in the Southern Alps, New Zealand. Quaternary Research 5, (1975). 2747.CrossRefGoogle Scholar
Refsnider, K.A., Laabs, B.J.C., Plummer, M.A., Mickelson, D.M., Singer, B.S., and Caffee, M.W. Last glacial maximum climate inferences from cosmogenic dating and glacier modeling of the western Uinta ice field, Uinta Mountains, Utah. Quaternary Research 69, (2008). 130144.Google Scholar
Schäfer, M., Gagliardini, O., Pattyn, F., and Le Meur, E. Applicability of the Shallow Ice Approximation inferred from model inter-comparison using various glacier geometries. The Cryosphere Discussions 2, 4 (2008). 557599.Google Scholar
Thomas, A.L., Henderson, G.M., Deschamps, P., Yokoyama, Y., Mason, A.J., Bard, E., Hamelin, B., Durand, N., and Camoin, G. Penultimate deglacial sea-level timing from uranium/thorium dating of Tahitian corals. Science 324, (2009). 11861189.Google Scholar
Thompson, R.S., and Anderson, K.H. Biomes of western North America at 18,000, 6000 and 0 14C yr BP reconstructed from pollen and packrat midden data. Journal of Biogeography 27, (2000). 555584.Google Scholar
Tweto, Ogden, Moench, R.H., and Reed, J.C. (1978). Geologic map of the Leadville 1 degree x 2 degrees quadrangle, northwestern Colorado. U.S. Geological Survey, Miscellaneous Investigations Series Map I-999, Scale 1:250,000.Google Scholar
Wagner, J.D.M., Cole, J.E., Beck, J.W., Patchett, P.J., Henderson, G.M., and Barnett, H.R. Moisture variability in the southwestern United States linked to abrupt glacial climate change. Nature Geoscience 3, (2010). 110113. http://dx.doi.org/10.1038/NGEO707 Google Scholar