Deglacial and Holocene vegetation and climatic changes at the southernmost tip of the Central Mediterranean from a direct land-sea correlation
International audience Despite a large number of studies, the long-term and millennial to centennial-scale climatic variability in the Mediterranean region during the last deglaciation and the Holocene is still debated, in particular in the Southern Central Mediterranean. In this 5 paper, we present...
Main Authors: | , , , , , , , , |
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Other Authors: | , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2012
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Subjects: | |
Online Access: | https://hal.science/hal-03280601 https://hal.science/hal-03280601/document https://hal.science/hal-03280601/file/Desprat-2012-CPD.pdf https://doi.org/10.5194/cpd-8-5687-2012 |
Summary: | International audience Despite a large number of studies, the long-term and millennial to centennial-scale climatic variability in the Mediterranean region during the last deglaciation and the Holocene is still debated, in particular in the Southern Central Mediterranean. In this 5 paper, we present a new marine pollen sequence (MD04-2797CQ) from the SiculoTunisian Strait documenting the regional vegetation and climatic changes in the Southern Central Mediterranean during the last deglaciation and the Holocene.The MD04-2797CQ marine pollen sequence shows that semi-desert plants dominated the vegetal cover in the Southern Central Mediterranean between 18 and 10 12.3 kyr BP indicating prevailing dry conditions during the deglaciation, even during the Greenland Interstadial (GI)-1. Such arid conditions likely restricted the expansion of the trees and shrubs despite the GI-1 climatic amelioration. Across the transition Greenland Stadial (GS)-1 – Holocene, Asteraceae-Poaceae steppe became dominant till 10.1 kyr. This record underlines with no chronological ambiguity that even15 though temperatures increased, deficiency in moisture availability persisted into the Early Holocene.Temperate trees and shrubs with heaths as oak forest understorey or heath maquis expanded between 10.1 and 6.6 kyr, while Mediterranean plants only developed from 6.6 kyr onwards. These changes in vegetal cover show that the regional climate in Southern Central Mediterranean was wetter during Sapropel 1 (S1) 20 and became drier during the Mid- to Late Holocene. Wetter conditions during S1 were likely due to increased winter precipitation while summers remained dry. We suggest, in agreement with published modelling experiments, that the increased melting of the Laurentide Ice Sheet between 10 to 6.8 kyr in conjunction with weak winter insolation played a major role in the development of winter precipitation maxima in the Mediter25 ranean region in controlling the strength and position of the North Atlantic storm track.Finally, our data provide ... |
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