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Correlation of geologic histories from 130 Alaskan glaciers with a record of solar variation suggests that multi-decadal to century-scale temperature variations in the North Pacific and Arctic sectors have been influenced by solar forcing over the past thousand years. Mountain glacier fluctuations are primarily a record of summer cooling and the composite glacial history from three climatic regions across Alaska shows ice expansions approximately every 200 years, compatible with a solar mode of variability. The modulating effects of the cold phases of the Pacific Decadal Oscillation and the Arctic Oscillation may, when in phase with decreased solar activity, serve to amplify cooling, forcing glacier advance.
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This review summarizes forefield and lacustrine records of glacier fluctuations in Alaska during the Holocene. Following retreat from latest Pleistocene advances, valley glaciers with land-based termini were in retracted positions during the early to middle Holocene. Neoglaciation began in some areas by 4.0 ka and major advances were underway by 3.0 ka, with perhaps two distinct early Neoglacial expansions centered respectively on 3.3–2.9 and 2.2–2.0 ka. Tree-ring cross-dates of glacially killed trees at two termini in southern Alaska show a major advance in the AD 550s–720s. The subsequent Little Ice Age (LIA) expansion was underway in the AD 1180s–1320s and culminated with two advance phases respectively in the...
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This review summarizes forefield and lacustrine records of glacier fluctuations in Alaska during the Holocene. Following retreat from latest Pleistocene advances, valley glaciers with land-based termini were in retracted positions during the early to middle Holocene. Neoglaciation began in some areas by 4.0 ka and major advances were underway by 3.0 ka, with perhaps two distinct early Neoglacial expansions centered respectively on 3.3–2.9 and 2.2–2.0 ka. Tree-ring cross-dates of glacially killed trees at two termini in southern Alaska show a major advance in the AD 550s–720s. The subsequent Little Ice Age (LIA) expansion was underway in the AD 1180s–1320s and culminated with two advance phases respectively in the...
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Correlation of geologic histories from 130 Alaskan glaciers with a record of solar variation suggests that multi-decadal to century-scale temperature variations in the North Pacific and Arctic sectors have been influenced by solar forcing over the past thousand years. Mountain glacier fluctuations are primarily a record of summer cooling and the composite glacial history from three climatic regions across Alaska shows ice expansions approximately every 200 years, compatible with a solar mode of variability. The modulating effects of the cold phases of the Pacific Decadal Oscillation and the Arctic Oscillation may, when in phase with decreased solar activity, serve to amplify cooling, forcing glacier advance.
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This review summarizes forefield and lacustrine records of glacier fluctuations in Alaska during the Holocene. Following retreat from latest Pleistocene advances, valley glaciers with land-based termini were in retracted positions during the early to middle Holocene. Neoglaciation began in some areas by 4.0 ka and major advances were underway by 3.0 ka, with perhaps two distinct early Neoglacial expansions centered respectively on 3.3–2.9 and 2.2–2.0 ka. Tree-ring cross-dates of glacially killed trees at two termini in southern Alaska show a major advance in the AD 550s–720s. The subsequent Little Ice Age (LIA) expansion was underway in the AD 1180s–1320s and culminated with two advance phases respectively in the...
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