Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-23T22:47:49.186Z Has data issue: false hasContentIssue false
  • English
  • Français

West African Paleoclimates during the Last Climatic Cycle Inferred from an Atlantic Deep-Sea Pollen Record

Published online by Cambridge University Press:  20 January 2017

Anne-Marie Lezine
Anne-Marie Lezine*
Affiliation:
Laboratoire de Géologie du Quaternaire, CNRS Luminy, Case 907, 13288 Marseille Cedex 9, France
Get access Rights & Permissions [Opens in a new window]

Abstract

Pollen studies of marine sediments from Atlantic deep-sea core V22-196 (13°50′ N-18°57′ W; 3728-m water depth) are used to reconstruct paleoclimates of north tropical west Africa since 140,000 yr B.P. High concentration of pollen, mainly from Saharan and arid littoral zones suggests a strengthened tradewind circulation since ca. 60,000 yr B.P. that became even stronger after 40,000 yr B.P. and reached a maximum 17,000 yr B.P. Periods of eolian transport of pollen to the Atlantic occurred about 94,000 and 105,000 yr B.P. and during Termination II. Conversely, high relative values of pollen from Sudanian and Guinean zones and from Mangrove and freshwater vegetation, coincident with maxima of dinocyst concentration, are interpreted as reflecting both strong fluvial inputs and the expansion of humid vegetation on the adjacent continent during wet periods dated between 140,000 and 118,000, 105,000 and 96,000, 92,000 and 73,000, 52,000 and 44,000 yr B.P. and 12,000 yr B.P. and the Holocene. The strong correlation of these results from the eastern tropical Atlantic with those from the Arabian Sea corroborates fluctuations of monsoon climate.

Type
Research Article
Information
Quaternary Research , Volume 35 , Issue 3-Part1 , May 1991 , pp. 456 - 463
Copyright
University of Washington

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Caratini, C. Tastet, J.P. Tissot, C. Frédoux, A. Sédimentation palynologique actuelle sur le plateau continental de Côte d'Ivoire Mémoires et Travaux de l'Ecole pratique des hautes Etudes Vol. 17 1987 Institut de Montpellier 69 100 Google Scholar
CLIMAP Project Members The last interglacial ocean Quaternary Research 21 1984 123 224 Google Scholar
Faegri, K. Iversen, J. Textbook of Pollen Analysis 3rd ed. 1975 Blackwell Oxford Google Scholar
Gasse, F. Stabell, B. Fourtanier, E. Van Yperen, Y. Freshwater diatom influx in interopical Atlantic: Relationships with continental records from Africa Quaternary Research 32 1989 229 243 Google Scholar
Hays, J.D. Perruzza, A. The significance of calcium carbonate oscillations in eastern equatorial Atlantic deep-sea sediments for the end of the Holocene warm interval Quaternary Research 2 1972 355 362 Google Scholar
Heusser, L. Morley, J. Structure and timing of the last deglaciation: examination of directly correlative terrestrial and oceanographic signals recorded in marine sediments Terra Abstracts 1 1989 11 Google Scholar
Hooghiemstra, H. Changes of major wind belts and vegetation zones in NW Africa 20,000 - 5000 yr B.P. as deduced from a marine pollen record near Cap Blanc Review of Paleobotany and Palynology 55 1988 101 140 CrossRefGoogle Scholar
Hooghiemstra, H. Variations of the African trade wind regime during the last 140,000 years: Changes in pollen flux evidenced by marine sediment records Leinen, M. Sarnthein, M. Paleoclimatology and Paleometeorology: Modern and Past Patterns of Global Atmospheric Transport 1989 Kluwer Academic Publishers 733 770 Google Scholar
Hooghiemstra, H. Bechler, A. Beug, H.J. Isopollen maps for 18,000 yr B.P. of the Atlantic offshore of northwest Africa: Evidence for paleo-wind circulation Paleoceanography 2 6 1987 561 582 CrossRefGoogle Scholar
Hooghiemstra, H. Agwu, C.O.C. Changes in the vegetation and trade winds in equatorial northwest Africa 140,000–70,000 yr B.P. as deduced from two marine pollen records Palaeogeography, Palaeoclimatology, Palaeoecology 66 1988 173 213 Google Scholar
Jansen, J.H.F. Van Weering, T.C.E. Gieles, R. Van Iperen, J. Middle and late quaternary oceanography and climatology of the Zaire-Congo fan and the adjacent eastern Angola basin Netherlands Journal of Sea Research 17 2–4 1984 201 249 Google Scholar
Kolla, V. Biscaye, P.E. Hanley, A.F. Distribution of quartz in late Quaternary Atlantic sediments in relation to climate Quaternary Research 11 1979 261 277 Google Scholar
Lézine, A.M. Edorh, T. Modern pollen deposition in West African Sudanian environments Review of Palaeobotany and Palynology 67 1–2 1991 41 58 Google Scholar
Lézine, A.M. Hooghiemstra, H. Land-sea comparisons during the last glacial-interglacial transition: Pollen records from West Tropical Africa Palaeogeography, Palaeoclimatology, Palaeoecology 79 1990 313 331 Google Scholar
Martinson, D.G. Pisias, N.G. Hays, J.D. Imbrie, J. Moore, T.C. Shakleton, N.J. Age dating and the orbital theory of the ice ages: Development of a high-resolution 0 to 300,000-Year chronostratigraphy Quaternary Research 27 1987 1 27 Google Scholar
Pokras, E.M. Mix, A.C. Eolian evidence for spatial variability of late quaternary climates in tropical Africa Quaternary Research 24 1985 137 149 Google Scholar
Prell, W.L. Van Campo, E. Coherent response of Arabian Sea upwelling and pollen transport to late Quaternary monsoonal winds Nature 323 1986 526 528 Google Scholar
Prell, W.L. Kutzbach, J.E. Monsoon variability over the past 150,000 years Journal of Geophysical Research 92 D7 1987 8411 8425 Google Scholar
Ritchie, J.C. Eyles, C.H. Haynes, C.V. Sediment and pollen evidence for an early to mid-Holocene humid period in the eastern Sahara Nature 314 1985 352 355 Google Scholar
Rossignol-Strick, M. Duzer, D. West African vegetation and climate since 22500 B.P. from deep-sea cores palynology Pollen et Spores 11 1–2 1979 105 134 Google Scholar
Rossignol-Strick, M. African monsoon, in immediate climate response to orbital insolation Nature 304 1983 46 49 CrossRefGoogle Scholar
Thiede, J. Aspects of the variability of the glacial and interglacial North Atlantic eastern boundary current (last 150,000 years) “Meteor” Forschung Ergebnisse C28 1977 1 36 Google Scholar
Turon, J.L. Londeix, L. Dinoflagellate assemblages in the western mediterranean (Alboran Sea), evidence of the evolution of paleoenvironments since the last glacial maximum Bulletin des Centre de Recherches et Exploration-Production Elf-Aquitaine 12-1 1988 313 344 Google Scholar
White, F. The Vegetation of Africa 1983 Unesco Paris Google Scholar