Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Understanding the Mechanisms behind the Northward Extension of the West African Monsoon during the Mid-Holocene
Stockholm University, Faculty of Science, Department of Meteorology .
Stockholm University, Faculty of Science, Department of Physical Geography.
Show others and affiliations
Number of Authors: 52017 (English)In: Journal of Climate, ISSN 0894-8755, E-ISSN 1520-0442, Vol. 30, no 19, p. 7621-7642Article in journal (Refereed) Published
Abstract [en]

Understanding the West African monsoon (WAM) dynamics in the mid-Holocene (MH) is a crucial issue in climate modeling, because numerical models typically fail to reproduce the extensive precipitation suggested by proxy evidence. This discrepancy may be largely due to the assumption of both unrealistic land surface cover and atmospheric aerosol concentration. In this study, the MH environment is simulated in numerical experiments by imposing extensive vegetation over the Sahara and the consequent reduction in airborne dust concentration. A dramatic increase in precipitation is simulated across the whole of West Africa, up to the Mediterranean coast. This precipitation response is in better agreement with proxy data, in comparison with the case in which only changes in orbital forcing are considered. Results show a substantial modification of the monsoonal circulation, characterized by an intensification of large-scale deep convection through the entire Sahara, and a weakening and northward shift (similar to 6.5 degrees) of the African easterly jet. The greening of the Sahara also leads to a substantial reduction in the African easterly wave activity and associated precipitation. The reorganization of the regional atmospheric circulation is driven by the vegetation effect on radiative forcing and associated heat fluxes, with the reduction in dust concentration to enhance this response. The results for the WAM in the MH present important implications for understanding future climate scenarios in the region and in teleconnected areas, in the context of projected wetter conditions in West Africa.

Place, publisher, year, edition, pages
2017. Vol. 30, no 19, p. 7621-7642
National Category
Earth and Related Environmental Sciences
Identifiers
URN: urn:nbn:se:su:diva-147854DOI: 10.1175/JCLI-D-16-0299.1ISI: 000411436700003OAI: oai:DiVA.org:su-147854DiVA, id: diva2:1153330
Available from: 2017-10-30 Created: 2017-10-30 Last updated: 2025-02-07Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full text

Authority records

Messori, GabrieleZhang, QiongPausata, Francesco S. R.

Search in DiVA

By author/editor
Messori, GabrieleZhang, QiongPausata, Francesco S. R.
By organisation
Department of Meteorology Department of Physical Geography
In the same journal
Journal of Climate
Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 198 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf