Isotopic Evidence for Glaciation During the Cretaceous Supergreenhouse

Andre Bornemann, Richard D. Norris, Oliver Friedrich, Britta Beckmann, Stefan Schouten, Jaap S. Sinninghe Damste, Jennifer Vogel, Peter Hofmann, Thomas Wagner

Research output: Contribution to journalArticle

188 Citations (Scopus)

Abstract

The Turonian ( 93.5 to 89.3 million years ago) was one of the warmest periods of the Phanerozoic eon, with tropical sea surface temperatures over 35 degrees C. High- amplitude sea- level changes and positive delta O-18 excursions in marine limestones suggest that glaciation events may have punctuated this episode of extreme warmth. New delta O-18 data from the tropical Atlantic show synchronous shifts similar to 91.2 million years ago for both the surface and deep ocean that are consistent with an approximately 200,000- year period of glaciation, with ice sheets of about half the size of the modern Antarctic ice cap. Even the prevailing supergreenhouse climate was not a barrier to the formation of large ice sheets, calling into question the common assumption that the poles were always ice- free during past periods of intense global warming.

Original languageEnglish
Pages (from-to)189-192
Number of pages4
JournalScience
Volume319
Issue number5860
DOIs
Publication statusPublished - 11 Jan 2008

Keywords

  • ANTARCTIC ICE-SHEET
  • ATMOSPHERIC CO2
  • RECORD
  • OCEAN
  • TEMPERATURES
  • RESOLUTION
  • CALCITE
  • WESTERN
  • CURVE

Cite this

Bornemann, A., Norris, R. D., Friedrich, O., Beckmann, B., Schouten, S., Damste, J. S. S., Vogel, J., Hofmann, P., & Wagner, T. (2008). Isotopic Evidence for Glaciation During the Cretaceous Supergreenhouse. Science, 319(5860), 189-192. https://doi.org/10.1126/science.1148777