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In the ad 1990s maritime glaciers in Scandinavia started to advance as a response to positive net mass balance in the preceding years, invoking annual advance rates in the order of ~50–60 m and a total frontal advance of 285 m (at Briksdalsbreen) in less than a decade. Records from six south Norwegian glaciers with continuous, annual front measurements are used to evaluate the magnitude, duration, climatic causes, and frontal time lags involved in this mass balance perturbation and the following frontal response of glaciers in southern Norway. A climate index based on meteorological data from Bergen unequivocally demonstrates that the main cause for the large glacier advances in Scandinavia in the 1990s was high winter precipitation linked to positive NAO index in the winters of 1988/1989, 1989/1990, 1992/1993, 1994/1995, 1997/1998, and 1999/2000. Less positive (or negative) glacier mass balance years were 1990/1991, 1993/1994, 1995/1997, and 1998/1999. Between 1996/1997 and 2009, Briksdalsbreen retreated 486 m (maximum annual retreat of 145 m in 2005/2006). The main cause of the significant glacier retreat in the early twenty-first century was a combined effect of reduced winter precipitation and higher summer temperatures. The glacier advance and following retreat phase back to the pre-advance position was completed in ~20 years, and is here termed the Briksdalsbre Event. This event has relevance for the identification and interpretation of decadal to centennial Holocene glacial events recorded in lacustrine and terrestrial sequences. [ABSTRACT FROM PUBLISHER]

Glacier length, though an indirect and delayed signal of climate conditions, can be used to determine the relationship between climate and glacier response. This study discusses glacier length change of eight outlet glaciers of Jostedalsbreen and Folgefonna (southern Norway), from the ‘Little Ice Age’ (LIA) until the present. A climate index was calculated from meteorological data from Bergen to determine the specific frontal time lags of the individual glaciers. Short and steep outlet glaciers, such as Briksdalsbreen, react rapidly to changes in climatic conditions, whereas long and gently descending glaciers, such as Nigardsbreen, need longer time to adjust to changes in temperature and/or precipitation. The time lag of Briksdalsbreen was about twice as long during the LIA as today. The correlations between North Atlantic Oscillation (NAO) and climate conditions and glacier fluctuations in Norway and the European western Alps were analysed. As the influence of the NAO on glacier fluctuations is most pronounced during winter, only the winter NAO index was considered. Fluctuations of maritime Norwegian glaciers are highly correlated with the NAO, whereas variations of more continental glaciers in the European western Alps are only partly influenced by the NAO and tend to be anti-correlated. However, the (anti-)correlation with the NAO is not constant during the record, and significantly weaker or even inversed during some periods. A comparison of the LIA glacier fluctuations in southern Norway and the European western Alps suggests that the asynchronous LIA maxima in the two regions may partly be attributed to multidecadal trends in the NAO. [ABSTRACT FROM AUTHOR]