Evidence of early Holocene glacial advances in southern South America from cosmogenic surface-exposure dating
Evidence of early Holocene glacial advances in southern South America from cosmogenic surface-exposure dating
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DOI：
10.1130/g21144.1
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发表时间：
2004-12
期刊：
影响因子：
5.8
通讯作者：
D. Douglass;B. Singer;M. Kaplan;R. P. Ackert;D. Mickelson;M. Caffee
中科院分区：
文献类型：
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作者：
D. Douglass;B. Singer;M. Kaplan;R. P. Ackert;D. Mickelson;M. Caffee
宇宙成因核素表面暴露测年表明，南美洲南部（46°S）的冰川提前了大约 10 年。 8.5 ka和6.2 ka，可能是由于南西风向北迁移导致该纬度降水增加和/或气温下降的结果。较早的进展早于目前公认的南美洲南部全新世冰川活动开始约 3000 年。这两项进展在时间上与格陵兰岛和世界其他地区发生的全新世气候振荡同步。如果这些事件之间存在因果关系，那么快速的气候变化似乎要么是外部强迫的（例如太阳变率），要么是在全球范围内迅速传播（例如大气过程）。
Cosmogenic nuclide surface-exposure dating reveals that glaciers in southern South America (46°S) advanced at ca. 8.5 and 6.2 ka, likely as a result of a northward migration of the Southern Westerlies that caused an increase in precipitation and/or a decrease in temperature at this latitude. The older advance precedes the currently accepted initiation of Holocene glacial activity in southern South America by ~3000 yr. Both of these advances are temporally synchronous with Holocene climate oscillations that occurred in Greenland and the rest of the world. If there are causal links between these events, then rapid climate changes appear to be either externally forced (e.g., solar variability) or are rapidly propagated around the globe (e.g., atmospheric processes).