nieuwe zoekopdracht
[ meld een fout in dit record ]mandje (0): toevoegen | toon Print deze pagina

Polar front shift and atmospheric CO2 during the glacial maximum of the Early Paleozoic Icehouse
Vandenbroucke, T.R.A.; Armstrong, H.A.; Williams, M.; Paris, F.; Zalasiewicz, J.A.; Sabbe, K.; Nõlvak, J.; Challands, T.J.; Verniers, J.; Servais, T. (2010). Polar front shift and atmospheric CO2 during the glacial maximum of the Early Paleozoic Icehouse. Proc. Natl. Acad. Sci. U.S.A. 107(34): 14983-14986. dx.doi.org/10.1073/pnas.1003220107
In: Proceedings of the National Academy of Sciences of the United States of America. The Academy: Washington, D.C.. ISSN 0027-8424; e-ISSN 1091-6490, meer
Peer reviewed article  

Beschikbaar in  Auteurs 

Trefwoord
    Marien
Author keywords
    chitinozoans; Ordovician; zooplankton biotopes; Hirnantian glaciations;climate belts

Auteurs  Top 
  • Vandenbroucke, T.R.A.
  • Armstrong, H.A.
  • Williams, M.
  • Paris, F.
  • Zalasiewicz, J.A.
  • Sabbe, K.
  • Nõlvak, J.
  • Challands, T.J.
  • Verniers, J.
  • Servais, T.

Abstract
    Our new data address the paradox of Late Ordovician glaciation under supposedly high pCO2 (8 to 22× PAL: preindustrial atmospheric level). The paleobiogeographical distribution of chitinozoan (“mixed layer”) marine zooplankton biotopes for the Hirnantian glacial maximum (440 Ma) are reconstructed and compared to those from the Sandbian (460 Ma): They demonstrate a steeper latitudinal temperature gradient and an equatorwards shift of the Polar Front through time from 55°–70° S to ~40° S. These changes are comparable to those during Pleistocene interglacial-glacial cycles. In comparison with the Pleistocene, we hypothesize a significant decline in mean global temperature from the Sandbian to Hirnantian, proportional with a fall in pCO2 from a modeled Sandbian level of ~8× PAL to ~5× PAL during the Hirnantian. Our data suggest that a compression of midlatitudinal biotopes and ecospace in response to the developing glaciation was a likely cause of the end-Ordovician mass extinction.

Alle informatie in het Integrated Marine Information System (IMIS) valt onder het VLIZ Privacy beleid Top | Auteurs 
IMIS is ontwikkeld en wordt gehost door het VLIZ, voor meer informatie contacteer .