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Palaeoenvironmental changes in the arid and sub arid belt (Sahara-Sahel-Arabian Peninsula) from 150 kyr to present

  • Philipp Hoelzmann
  • Françoise Gasse
  • Lydie M. Dupont
  • Ulrich Salzmann
  • Michael Staubwasser
  • Dirk C. Leuschner
  • Franko Sirocko
Part of the Developments in Paleoenvironmental Research book series (DPER, volume 6)

The PEP III Arid to Subarid Belt includes the largest hot desert in the world, the Sahara- Arabian desert and the Sahel zone. The region of interest extends south of the Atlas Mountains and south and east of the Mediterranean Sea to approximately 10 °N and shows a broadly zonal pattern with a varying seasonal distribution of precipitation. In the north (ca. 20–23 °N), rainfall results from the southward displacement of the midlatitude westerlies during winter whereas the south is governed by seasonal northward migration of the Intertropical Convergence Zone (ITCZ). Contraction and expansion phases of these presently semi-arid to hyper-arid desert areas result from significant changes in local precipitation. Palaeoenvironmental records from Northern Africa (north of 10 °N) and the surrounding seas document long-term changes in the magnitude and extent of the African monsoon in response to orbitally-forced changes in insolation. However, marine records as well as terrestrial palaeohydrological indicators (e.g., lakes, speleothems, rivers, pollen and charcoal) show that there have been changes in the hydrological cycle superimposed on the long-term waxing and waning of the monsoon which cannot be explained exclusively by changes in insolation. These fluctuations in space, time and magnitude were on a regional to continental scale.

Here, we review available data on near-surface palaeohydrological indicators and vegetational changes in arid North Africa and the Arabian Peninsula as well as changes in the intensity of the South Asian Monsoon identified from marine sediments of the Arabian Sea. A comparison of regional environmental changes can clarify relations between the environment and changes in the Earth’s climate system. Each data-set is initially presented independently because they represent heteregeneous records from different regions and time periods and thereby emphasise their potential to provide evidence of continental chronostratigraphic palaeoenvironmental changes. Data-sets of lake status and vegetational change are complementary as they strongly reflect hydrological variation. Deep-sea sediments from the Arabian Sea were used to generate continuous records of oceanic upwelling, continental humidity, and dust and river discharge, that are closely related to palaeoenvironmental changes on the surrounding continents.After presenting the individual data-sets we compare the palaeoclimatic reconstructions derived from the different types of evidence.

Keywords

Last Glacial Maximum Arabian Peninsula Marine Isotope Stage South Asian Monsoon Oxygen Minimum Zone 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer 2004

Authors and Affiliations

  • Philipp Hoelzmann
    • 1
  • Françoise Gasse
    • 2
  • Lydie M. Dupont
    • 3
  • Ulrich Salzmann
    • 4
  • Michael Staubwasser
    • 5
  • Dirk C. Leuschner
    • 6
  • Franko Sirocko
    • 7
  1. 1.LECO Instrumente GmbHGermany
  2. 2.Centre Européen de Recherche et d'Enseignement, de Géosciences de l’ Environement (CEREGE)University of Aix-Marseille IIFrance
  3. 3.Fachbereich GeowissenschaftenUniversität BremenGermany
  4. 4.Zentrum für Marine Tropenoekologie (ZMT)Germany
  5. 5.Department of Earth SciencesUniversity of OxfordUK
  6. 6.Institut für Geophysik und GeologieUniversität LeipzigGermany
  7. 7.Institut für GeowissenschaftenUniversität MainzGermany

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