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Lake sediment cores and cosmogenic exposure (CE) dates constrain the pattern of deglaciation and evolution of climate across Baffin Island since the last glacial maximum (LGM). CE dating of erratics demonstrates that the northeastern coastal lowlands became ice-free ca.14ka as the Laurentide Ice Sheet (LIS) receded from its LGM margin on the continental shelf. Coastal lakes in southeastern Baffin Island

A global overview of glacier advances and retreats (grouped by regions and by millennia) for the Holocene is compiled from previous studies. The reconstructions of glacier fluctuations are based on 1) mapping and dating moraines defined by 14 C, TCN, OSL, lichenometry and tree rings (discontinuous records/time series), and 2) sediments from proglacial lakes and speleothems (continuous records/ time series). Using 189 continuous and discontinuous time series, the long-term trends and centennial fluctuations of glaciers were compared to trends in the recession of Northern and mountain tree lines, and with orbital, solar and volcanic studies to examine the likely forcing factors that drove the changes recorded. A general trend of increasing glacier size from the earlyemid Holocene, to the late

Based on an exponential relationship between winter precipitation as snow and summer temperature at the equilibrium-line altitude (ELA) on modern Norwegian glaciers, it is possible to reconstruct former variations in winter precipitation by combining reconstructed ELAs with independent proxies for summer temperature. Glaciers respond mainly to changes in summer temperature and winter precipitation. By using the exponential relationship between summer

Variations in the North Atlantic Oscillation (NAO) index are reflected in glacier mass balance records in western Scandinavia. The NAO index is best correlated with the net mass balance on maritime glaciers in southern Norway. Holocene glacier variations of maritime glaciers in western Scandinavia may therefore reflect winter precipitation changes and thus be a proxy for winter climate variability in

ABSTRACT Here we present a Holocene record of glacier activity as documented in physical sediment properties from the distal glacier-fed lake Sørsendalsvatna (918m asl), located 35 km inland from the coast in Western Norway. The up-valley cirque glacier Blåbreen has an altitudinal extent from 1420 to 960m asl, with a present mean equilibrium-line altitude (ELA) close to 1050m asl. Three cores were collected from Sørsendalsvatna in 2005 using a piston corer from a raft. Standard sedimentological and geochemical parameters such as loss-on-ignition (LOI), dry bulk density (DBD), magnetic susceptibility (MS), grain-size distribution (GS) and scanning x-ray fluorescence (XRF) were measured in all three cores. The amount of detrital input was further determined by means of visible reflectance spectroscopy (VIS-RS). Multivariate data sets were compared with each other by calculating the multivariate correlation coefficient (RV-coefficient), and the common signals of multivariate data sets were extracted by means of principle component analysis (PCA). The age-depth model is based on twelve 14C dates and was constructed by smoothing spline interpolation using the 'classical' age-modelling algorithm available in Clam.R. Uncertainties of the age-model are moderate (100 years) back to 8300 cal BP and increase to 400 years before 9500 cal BP. The geochemical elements Si, K, Ca, Ti, Fe and Sr have significant count rates as measured by an ITRAX core scanner. Count rates of different geochemical elements are in accordance with each other, and the only significant PC-axis explains 89% of the variance. Further LOI, DBD, MS and VIS-RS are highly correlated among each other and with the XRF data (RV= 0.95). Applying PCA to the combined data sets, we find one significant axis that explains 92% of the variance. Grain-size data, however, do not show any accordance with other sedimentological parameters (RV=0.28). LOI, DBD, MS, XRF and VIS-RS are interpreted as indicative of increased deposition of sediments derived from glacial abrasion. The common signal of these data sets was extracted by means of PCA and is interpreted to vary in concert with the changing glacier ELA. The ELA increased sharply between 9500 and 9300 cal BP. This increase is marked by a change in the sediments, from gray silty-clay to brown gyttja. Values remained constant between 9300 and 8300 cal BP followed by a pronounced decrease lasting until 7800 cal BP, with minimum values recorded around 8000 cal BP. This ELA lowering is most probably associated with the 8.2k Event recorded in Greenland ice cores, in Norway termed the Finse Event. The highest ELA during the Holocene was recorded between 7800 and 6000 cal BP followed by a decrease between 6000 and 5500 cal BP. The ELA was rather stable between 5500 and 3500 cal BP followed by a steady decrease lasting until 1500 cal BP where the sediment is again composed of gray silty-clay. During the last 1500 years the ELA seems rather stable again, showing the lowest values since the end of the early Holocene deglaciation. In Sørsendalsvatna, no clear signal of the 'Little Ice Age' is detectable, possibly due to a hiatus in the upper part of the cores.

The archaeological investigations in the mid part of Gudbrandsdalen in 2011 and 2012 revealed a number of flood/avalanche horizons, of which «Forrskredet» (ca 350–200 BC), «Gammelofsen» (ca 50–1 BC), and «Merovingertidsofsen» (ca AD 600–800) were recognised as the major events at the investigated sites. Local topography and weather conditions (such as extreme weather events) and more long-term climatic trends were most likely the triggering factors for these events. During the time interval for Forrskredet, glaciers in Jotunheimen were in an advanced position, winter precipitation in mountains in western Norway (Jostedalsbreen) was relatively high, and summer temperatures in Scandinavia, as reconstructed from tree rings, were relatively high. Gammelofsen occurred during a period with relatively small glaciers in Jotunheimen as winter precipitation was increasing in western Norway and summer temperatures were rising in Scandinavia. During Merovingertidsofsen, glaciers in Jotunheimen were in an advanced position, winter precipitation was rapidly increasing in western Norway, and summer temperatures were relatively low in Scandinavia. The prehistoric flood and avalanche events in Gudbrandsdalen, such as the subsequent historic flood events, in particular «Storofsen» (1789) and «Storflaumen» (1860), certainly had a severe impact on settlement and farming.

E6-prosjektet Gudbrandsdalen er det mest omfattende utgravningsprosjektet som er gjennomført i Oppland noensinne, og har sin bakgrunn i etableringen av ny E6 gjennom dalføret. I 2011 og 2012 gjennomførte Kulturhistorisk museum utgravninger på 64 steder i kommunene Sør-Fron, Nord-Fron og Sel, og utgravningene avdekket blant annet en frem til da ukjent flom-, bosetnings-og jordbrukshistorikk. Omfattende undersøkelser ble også gjort i utmarka, der et stort antall kull-og fangstgroper ble gravd ut. Det samlede vitenska-pelige materialet fra prosjektet har endret forståelsen av Gudbrandsdalens arkeologi og gitt ny kunnskap om hvordan samfunnet i dalføret utviklet seg i jernalderen og middelalderen. Denne boken presenterer de viktigste faglige resultatene, setter resultatene inn i en større kulturhistorisk sammenheng og gjør rede for kunnskapsstatusen på viktige fagområder innenfor Gudbrandsdalens arkeologi.

The melting of perennial ice patches globally is uncovering a fragile record of alpine activity, especially hunting and the use of mountain passes. When rescued by systematic fieldwork (glacial archaeology), this evidence opens an unprecedented window on the chronology of high-elevation activity. Recent research in Jotunheimen and surrounding mountain areas of Norway has recovered over 2000 finds—many associated with reindeer hunting (e.g. arrows). We report the radiocarbon dates of 153 objects and use a kernel density estimation (KDE) method to determine the distribution of dated events from ca 4000 BCE to the present. Interpreted in light of shifting environmental, preservation and socioeconomic factors, these new data show counterintuitive trends in the intensity of reindeer hunting and other high-elevation activity. Cold temperatures may sometimes have kept humans from Norway's highest elevations, as expected based on accessibility, exposure and reindeer distributions. In times of increasing demand for mountain resources, however, activity probably continued in the face of adverse or variable climatic conditions. The use of KDE modelling makes it possible to observe this patterning without the spurious effects of noise introduced by the discrete nature of the finds and
the radiocarbon calibration process.