Holocene glacier variation chronology of the Smørstabbtindan massif,Jotunheimen,southern Norway,and the recognition of century- to millennial-scale European Neoglacial Events

New stratigraphic evidence for the Holocene history of three glaciers in central Jotunheimen, southern Norway, is presented and the implications for century- to millennial-scale glacier and climatic variability are considered. Minerogenic layers in seven stream-bank mires, flooded episodically by glaciofluvial meltwater, are dated by 79 new radiocarbon age estimates. A revised chronology for glacier variations in Smørstabbtindan suggests a three-phase Holocene: (1) an early-Holocene deglaciation phase (11500—9500 cal. BP) characterized by readvances of ice-sheet remnants; (2) a mid-Holocene phase with relatively small or absent glaciers (9500—5000 cal. BP); and (3) a late-Holocene phase of enlarged and fluctuating glaciers (the last 5000 years). Seven millennial-scale neoglacial events (Smørstabbtindan I—VII), during which glaciers were larger than at present for most of the time, are dated to: >10 400—9600 (Erdalen Event), 8400—7650 (Finse Event), 4800—3900, 3200—2550, 2350—1700, 1400—750 and 500—0 cal. BP (`Little Ice Age'). Two or more century-scale events are nested within each millennial-scale event. Based on the timing of neoglacial maxima, the record from Smørstabbtindan is combined with comparable reconstructions from southern Norway to indicate at least 17 century- to millennial-scale Southern Norwegian Neoglacial Events. A similar approach to records from the Swiss and Austrian Alps identifies around 23 Alpine Neoglacial Events. This leads to the recognition of 13 European Neoglacial Events that are at least continental in extent but seem to be imperfectly correlated with episodes of low solar irradiance, which suggests that other climatic forcing factors are also involved, including volcanic aerosols and, in the early Holocene, freshwater outbursts into the northern Atlantic Ocean. Local to regional patterns in glacier behaviour, particularly in relation to century-scale events, may be accounted for by differences in glacier size and geometry, topography and atmospheric circulation patterns; whereas the three Holocene multimillennial phases appear to reflect the Earth's orbital variations.