. This review focuses on the development of the ‘Little Ice Age’ as a glaciological and climatic concept, and evaluates its current usefulness in the light of new data on the glacier and climatic variations of the last millennium and of the Holocene. ‘Little Ice Age’ glacierization occurred over about 650 years and can be defined most precisely in the European Alps (c. AD 1300–1950) when extended glaciers were larger than before or since. ‘Little Ice Age’ climate is defined as a shorter time interval of about 330 years (c. AD 1570–1900) when Northern Hemisphere summer temperatures (land areas north of 20°N) fell significantly below the AD 1961–1990 mean. This climatic definition overlaps the times when the Alpine glaciers attained their latest two highstands (AD 1650 and 1850). It is emphasized, however, that ‘Little Ice Age’ glacierization was highly dependent on winter precipitation and that ‘Little Ice Age’ climate was not simply a matter of summer temperatures. Both the glacier‐centred and the climate‐centred concepts necessarily encompass considerable spatial and temporal variability, which are investigated using maps of mean summer temperature variations over the Northern Hemisphere at 30‐year intervals from AD 1571 to 1900. ‘Little Ice Age’‐type events occurred earlier in the Holocene as exemplified by at least seven glacier expansion episodes that have been identified in southern Norway. Such events provide a broader context and renewed relevance for the ‘Little Ice Age’, which may be viewed as a ‘modern analogue’ for the earlier events; and the likelihood that similar events will occur in the future has implications for climatic change in the twenty‐first century. It is concluded that the concept of a ‘Little Ice Age’ will remain useful only by (1) continuing to incorporate the temporal and spatial complexities of glacier and climatic variations as they become better known, and (2) by reflecting improved understanding of the Earth‐atmosphere‐ocean system and its forcing factors through the interaction of palaeoclimatic reconstruction with climate modelling.

The history of Holocene glacier variations of Flatebreen, an independent glacier close to the SW part of the Jostedalsbreen ice cap, has been reconstructed from lacustrine sediments in the proglacial lake Jarbuvatnet. The sedimentary succession shows evidence of three maini episodes of Holocene glacier expansion.The first is recorded in the basal part of the core up to 370 cm. According to the age/depth relationship in the sediment core (based on 12 AMS radiocarbon dates), this glacier expansion episode terminated about 10200 cal. yr BP. The second major glacier phase lasted from 8400 to 8100 cal. yr BP, while the third was initiated around 4000 cal. yr BP and has continued up to the present. At 43 cm in the core, the medium silt content increases significantly, accompanied by a minor increase in the sand content. This textural change is interpreted as the first time that the tenninus of Flatebreen extended inlto an] upstream lake at 1083 m a.s.l. The age model suggests that this event took place around 800 cal. yr BP (-AD 1150), as a response to the initial 'Little Ice Age' glacier expansion after the 'Mediaeval Warm Period'. By using a Holocene-inferred summer-temperature curve from central southern Norway in the exponential relationship between annual winter precipitation (snow) and ablation-season temperature at the ELA, periods of higher winter precipitation than the 1961-90 nomial in the Jostedalsbreen region are inferred for cal. yr BP, and from 900 cal. yr BP to the present. The intervening periods of lower than normal winter precipitation correlate with periods of enhanced ice-rafting in the North Atlantic.

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