Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum
Temperature-index modeling is used to determine the magnitude of temperature depression on the Blanca Massif, Colorado, required to maintain steady-state mass balances of nine reconstructed glaciers at their extent during the Last Glacial Maximum (LGM). The mean temperature depression thus determine...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-08-01
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| Series: | Quaternary |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2571-550X/4/3/27 |
| _version_ | 1797517432677466112 |
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| author | Keith A. Brugger Eric M. Leonard Kurt A. Refsnider Peter Dolan |
| author_facet | Keith A. Brugger Eric M. Leonard Kurt A. Refsnider Peter Dolan |
| author_sort | Keith A. Brugger |
| collection | DOAJ |
| description | Temperature-index modeling is used to determine the magnitude of temperature depression on the Blanca Massif, Colorado, required to maintain steady-state mass balances of nine reconstructed glaciers at their extent during the Last Glacial Maximum (LGM). The mean temperature depression thus determined is ~8.6 +0.7/−0.9 °C where the uncertainties account for those inherent in the glacier reconstructions, in model parameters (e.g., melt factors), and possible modest changes in LGM precipitation. Associated equilibrium-line altitudes (ELAs) exhibit a statistically significant directional dependency being lower toward the north and east. Under the assumption that regional temperature change was uniform, required changes in precipitation vary systematically—also exhibiting a directional dependency coinciding with that in ELAs—and indicate increases (over modern) occurred on the eastern side of the massif while decreases occurred on the western side. This disparity represents a strengthening of a precipitation asymmetry, particularly winter precipitation, which exists today. The modern precipitation asymmetry may be a consequence of snow being blown over to the eastern side of the massif (advective transport) by southwesterly flow. Intensification of this flow during the LGM would have enhanced advection, and augmented snow accumulation on glaciers, thus explaining the lower ELAs and increased precipitation on that side of the massif. |
| first_indexed | 2024-03-10T07:16:33Z |
| format | Article |
| id | doaj.art-87a7f6f1da78423497c7c0b6a35e2d5a |
| institution | Directory Open Access Journal |
| issn | 2571-550X |
| language | English |
| last_indexed | 2024-03-10T07:16:33Z |
| publishDate | 2021-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Quaternary |
| spelling | doaj.art-87a7f6f1da78423497c7c0b6a35e2d5a2023-11-22T15:02:11ZengMDPI AGQuaternary2571-550X2021-08-01432710.3390/quat4030027Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial MaximumKeith A. Brugger0Eric M. Leonard1Kurt A. Refsnider2Peter Dolan3Geology Discipline, University of Minnesota, Morris, MN 56267, USADepartment of Geology, Colorado College, Colorado Springs, CO 80903, USA101 W Goodwin St #3849, Prescott, AZ 86302, USAStatistics and Computer Science Disciplines, University of Minnesota, Morris, MN 56267, USATemperature-index modeling is used to determine the magnitude of temperature depression on the Blanca Massif, Colorado, required to maintain steady-state mass balances of nine reconstructed glaciers at their extent during the Last Glacial Maximum (LGM). The mean temperature depression thus determined is ~8.6 +0.7/−0.9 °C where the uncertainties account for those inherent in the glacier reconstructions, in model parameters (e.g., melt factors), and possible modest changes in LGM precipitation. Associated equilibrium-line altitudes (ELAs) exhibit a statistically significant directional dependency being lower toward the north and east. Under the assumption that regional temperature change was uniform, required changes in precipitation vary systematically—also exhibiting a directional dependency coinciding with that in ELAs—and indicate increases (over modern) occurred on the eastern side of the massif while decreases occurred on the western side. This disparity represents a strengthening of a precipitation asymmetry, particularly winter precipitation, which exists today. The modern precipitation asymmetry may be a consequence of snow being blown over to the eastern side of the massif (advective transport) by southwesterly flow. Intensification of this flow during the LGM would have enhanced advection, and augmented snow accumulation on glaciers, thus explaining the lower ELAs and increased precipitation on that side of the massif.https://www.mdpi.com/2571-550X/4/3/27Last Glacial Maximumpaleoglacier reconstructionpaleoclimatetemperature-index modelBlanca MassifSangre de Cristo Mountains |
| spellingShingle | Keith A. Brugger Eric M. Leonard Kurt A. Refsnider Peter Dolan Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum Quaternary Last Glacial Maximum paleoglacier reconstruction paleoclimate temperature-index model Blanca Massif Sangre de Cristo Mountains |
| title | Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum |
| title_full | Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum |
| title_fullStr | Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum |
| title_full_unstemmed | Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum |
| title_short | Climate on the Blanca Massif, Sangre de Cristo Mountains, Colorado, USA, during the Last Glacial Maximum |
| title_sort | climate on the blanca massif sangre de cristo mountains colorado usa during the last glacial maximum |
| topic | Last Glacial Maximum paleoglacier reconstruction paleoclimate temperature-index model Blanca Massif Sangre de Cristo Mountains |
| url | https://www.mdpi.com/2571-550X/4/3/27 |
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