Climatic changes during the last 35,000 years as indicated by land, sea, and air data
Detailed climatic records from land (glaciation curves, fossil records, etc.), sea (eustatic changes, deep‐ses date), and air (Greenland 0 18 curve) are almost identical for the last 35,000 years. This cannot be a mere coincidence: it indicates that even minor fluctuations are caused by global clima...
Published in: | Boreas |
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Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
1973
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Subjects: | |
Online Access: | http://dx.doi.org/10.1111/j.1502-3885.1973.tb00248.x https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1502-3885.1973.tb00248.x https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1502-3885.1973.tb00248.x |
Summary: | Detailed climatic records from land (glaciation curves, fossil records, etc.), sea (eustatic changes, deep‐ses date), and air (Greenland 0 18 curve) are almost identical for the last 35,000 years. This cannot be a mere coincidence: it indicates that even minor fluctuations are caused by global climatic changes. The various records seem to be easily correlated with each other. The Last Ice Age is characterized by drastic changes between colder and warmer periods. The Present (Flandrian) Interglacial (Holocene Epoch) is also characterized by climatic fluctuations, although of minor amplitude. Analysis of peaks and bottoms in six Atlantic deep‐sea cores gives a climatic sequence identical to the eustatic transgression/regression sequence, indicating the recording of global short‐term warm/cold fluctuations. From these fluctuations, the climatic cyclicity was calculated. Two drastically frequency‐changing cycles were found, one varying from 230 to 1,000 years and one from 1,000 to 3,600 years. A third cycle of 21,000 years was also estabished. The transition from the Last Ice Age to the Present Interglacial is marked by three major steps towards interglacial conditions; viz. at 12,7000, 10,000 and 9,300 radiocarbon years B. P. The 10,000 boundary has earler been suggested as the Pleistocene/Holocene boundary. |
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