Geography Lecture Series

Fri. May. 4 12:30 PM - Fri. May. 4 01:20 PM
Location: 5L24 Lockhart Hall

Exceptional polar amplification of Eocene climate under modest greenhouse gas forcing: Implications for the future

Dr. Alexander P. Wolfe
Department of Biological Sciences, University of Alberta

In this public talk, Dr. Wolfe will discuss the capability of models to project future climate scenarios by looking into the climatic past of the Canadian subarctic.  Sediments from the middle Eocene (~47–38 Ma) have been used to provide reconstructions of past climate and atmospheric CO₂ levels. These reconstructions are based on information from pollen and plant fossils preserved in the sediment and show that temperatures from this time period were ~10˚C warmer than predicted by global Earth systems models for the CO₂ levels at the time. This may be due to changes in synoptic scale (1,000’s km) circulation of air in polar regions in the middle Eocene, something that is presently occurring over the Arctic Ocean with the slowing of the polar jet stream. These results indicate that future climate projections are likely grossly underestimated.

Dr. Wolfe's research interests include: paleobiology and global environmental change; paleoenvironmental reconstruction on geological and anthropogenic time-scales; method development in paleobiology: non-destructive techniques including visible-near-infrared reflectance spectroscopy (VNIR), Fourier-transform infrared spectroscopy (FTIR), and time of flightsecondary-ion mass spectrometry (ToF-SIMS); evolutionary history and the early fossil record of Ochrophyte algae (diatoms and chrysophytes); applications of conifer resins and amber to problems in paleoecology and paleoclimatology; preservation and evolution of integumentary structures in theropod dinosaurs; biomolecular preservation (pigments and proteins) in lagerstätte-quality sedimentary deposits; chronology, geochemistry, and diagenesis of lake sediments; anthropogenic impacts and lake ecosystems cycling.