title: Younger Dryas deglaciation of Scotland driven by warming summers.
abstract: The Younger Dryas Stadial (YDS; ∼ 12,900-11,600 y ago) in the Northern Hemisphere is classically defined by abrupt cooling and renewed glaciation during the last glacial-interglacial transition. Although this event involved a global reorganization of atmospheric and oceanic circulation [Denton GH, Alley RB, Comer GC, Broecker WS (2005) Quat Sci Rev 24:1159-1182], the magnitude, seasonality, and geographical footprint of YDS cooling remain unresolved and pose a challenge to our understanding of abrupt climate change. Here, we present a deglacial chronology from Scotland, immediately downwind of the North Atlantic Ocean, indicating that the Scottish ice cap disintegrated during the first half of the YDS. We suggest that stratification of the North Atlantic Ocean resulted in amplified seasonality that, paradoxically, stimulated a severe wintertime climate while promoting warming summers through solar heating of the mixed layer. This latter process drove deglaciation of downwind landmasses to completion well before the end of the YDS.
authors.affiliation: Climate Change Institute and School of Earth and Climate Sciences, University of Maine, Orono, ME 04469.
authors.forename: Gordon R M
authors.initials: GR
authors.lastname: Bromley
authors.forename: Aaron E
authors.initials: AE
authors.lastname: Putnam
authors.forename: Kurt M
authors.initials: KM
authors.lastname: Rademaker
authors.forename: Thomas V
authors.initials: TV
authors.lastname: Lowell
authors.forename: Joerg M
authors.initials: JM
authors.lastname: Schaefer
authors.forename: Brenda
authors.initials: B
authors.lastname: Hall
authors.forename: Gisela
authors.initials: G
authors.lastname: Winckler
authors.forename: Sean D
authors.initials: SD
authors.lastname: Birkel
authors.forename: Harold W
authors.initials: HW
authors.lastname: Borns
mesh_terms: D001267:Atlantic Ocean; D002138:Calibration; D005843:Geography; D046448:Ice Cover; D055110:Radiometric Dating; D012606:Scotland; D012621:Seasons; D013696:Temperature; D013997:Time Factors
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