title: Millennial climatic fluctuations are key to the structure of last glacial ecosystems.
abstract: Whereas fossil evidence indicates extensive treeless vegetation and diverse grazing megafauna in Europe and northern Asia during the last glacial, experiments combining vegetation models and climate models have to-date simulated widespread persistence of trees. Resolving this conflict is key to understanding both last glacial ecosystems and extinction of most of the mega-herbivores. Using a dynamic vegetation model (DVM) we explored the implications of the differing climatic conditions generated by a general circulation model (GCM) in "normal" and "hosing" experiments. Whilst the former approximate interstadial conditions, the latter, designed to mimic Heinrich Events, approximate stadial conditions. The "hosing" experiments gave simulated European vegetation much closer in composition to that inferred from fossil evidence than did the "normal" experiments. Given the short duration of interstadials, and the rate at which forest cover expanded during the late-glacial and early Holocene, our results demonstrate the importance of millennial variability in determining the character of last glacial ecosystems.
authors.affiliation: School of Biological and Biomedical Sciences, Durham University, Durham, United Kingdom. brian.huntley@durham.ac.uk
authors.forename: Brian
authors.initials: B
authors.lastname: Huntley
authors.forename: Judy R M
authors.initials: JR
authors.lastname: Allen
authors.forename: Yvonne C
authors.initials: YC
authors.lastname: Collingham
authors.forename: Thomas
authors.initials: T
authors.lastname: Hickler
authors.forename: Adrian M
authors.initials: AM
authors.lastname: Lister
authors.forename: Joy
authors.initials: J
authors.lastname: Singarayer
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Stuart
authors.forename: Martin T
authors.initials: MT
authors.lastname: Sykes
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Valdes
mesh_terms: D002980:Climate; D017753:Ecosystem; D046448:Ice Cover