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The influence of the 'Little Ice Age' (LIA) on the glaciers of Svalbard has been well documented for a long time. This paper presents new data on the LIA maximum glacier extent and retreat by aerial photo interpretation and Geographic Information Systems (GIS) tools. We also make cartography where all results are shown in greater detail. During the LIA maximum, we find that the glacier area of Svalbard was 38,871 km2, and since then, the total glacier area loss in the archipelago has been 5096 km2 (13.1%). The total current glaciated area from the late 2000s is 33,775 km2. Since the LIA, the glaciers in the main islands of the archipelago have retreated by 12.8% in Spitsbergen, 13.4% in Nordaustlandet, and 16.7% in Barentsøya and Edgeøya. The analysis of the LIA maximum glacier extent in the different major drainage basins shows important differences; about 100 years ago, some glacier basins were more than 19% larger in the western and central regions of Spitsbergen, or even more than 23% larger in southern Nordaustlandet, while other small basins found in the northeast of this island were barely 1% larger. The greatest retreats are found in the tidewater glaciers, more variable and responsive to the water temperature changes, water dynamics, and bathymetry. In addition, the advances at some of these glaciers may correspond with surges, which means that the rapid retreats are caused by the post-surging phases as well as climate. The conclusions of this research point out an important ice loss in all of Svalbard since the LIA and the high vulnerability of this Arctic archipelago to global warming. [ABSTRACT FROM AUTHOR]

The topic of this paper is the importance of climate for the population and settlement in medieval and early modern times. Were the demographic crises caused by crop failure and famine or by disease? I begin by reviewing European research (particularly English) relating to the issue. The views of Norwegian historians regarding the causes of the agrarian crisis in the late Middle Ages are then examined. Hasund (Hasund S, 1919, 1944, Den store mannedauden. Or Noregs bondesoge. Glytt og granskingar II, Oslo, pp. 82–161. First printed in Beretning om Norges Landbrukshøiskoles virksomhet 1918–1919) claimed it was the plagues, not the climate, that held the population at a low level to the end of the Middle Ages, a view that has been repeated in recent years by such researchers as Lunden (Lunden K, 2002, Norges landbrukshistorie II, 1350–1814. Frå svartedauden til 17. mai. Oslo) and Moseng (Moseng OG, 2006, Den flyktige pesten. Vilkårene for epidemier i Norge i seinmiddelalder og tidlig nytid. Oslo). This paper claims that the role of the climate has been underestimated, in particular that the climatic shock of several bad years in a row directly and indirectly brought appreciable excess mortality in a country situated so far north. ‘Bad’ years demonstrated through dendrochronology are in many cases reflected in documentary evidence concerning poor corn harvests and high mortality. [ABSTRACT FROM PUBLISHER]

This Special Issue of The Holocene contains 16 research papers based on a symposium at the 11th International Meeting of the European Union of Geosciences held in Strasbourg in April 2001. The aim of the symposium was a state-of-the-art assessment of empirical studies of postglacial marine and terrestrial climatic archives and their integration with numerical climate models. This editorial places the individual papers in the broader context of natural climate variability and anthropogenic impacts on the global climate system, regional differences in climate between maritime and continental areas, and the need for an improved theoretical basis for understanding the underlying causes of environmental change. The focus of the Special Issue is the dynamic and relatively well-understood climate of the North Atlantic and the European realm, where, in relation to the steepest offshore temperature gradient on Earth, observational data are abundant and many recent advances have been made in climate reconstruction from proxy archives. The editorial also contains a summary and overview of the papers included in the four main sections of the Special Issue, which emphasize: (1) numerical modelling experiments; (2) models of glacier buildup and equilibrium-line altitude; (3) marine and terrestrial proxy records of climatic change; and (4) multiproxy palaeoenvironmental reconstruction of a Portuguese lagoonal system. [ABSTRACT FROM AUTHOR]

Bleicher (2013) discussed interpretations proposed by Magny (2004) that Holocene lake-level fluctuations in west-central Europe suggest possible solar forcing of climate. He pointed out that the method used by Magny (2004) is a variant of a cumulative probability function (CPF) and cannot prove solar forcing of central European lake-level changes. He concluded that only few episodes of lake-level changes are climatically driven and that non-climatic factors were dominating. While Bleicher’s paper offers a stimulating contribution to the general debate on CPFs, the present comment is based on an approach which, in contrast to CPFs, excludes any consideration of variations in the probabilities over the time intervals given by calibration of 14C dates, as well as any distinction between types of dates (radiocarbon versus tree ring). It produces a revised pattern of the mid-European high lake-level events for the whole Holocene, supporting the hypothesis proposed in Magny (2004). Comparisons with other regional and North Atlantic palaeoclimatic records suggest that, without excluding other forcing factors, the successive high lake-level events recognised in west-central Europe reflect a combination of three main forcing factors acting on millennial and centennial scales, i.e. orbitally driven changes in insolation, impacts of deglacial outbursts and, possibly, variations in solar activity. Finally, it is clear that further investigations are still needed in order to improve the chronological data set for mid-European lake-level fluctuations, with particular attention to better defining the beginning and end of events. [ABSTRACT FROM AUTHOR]

Species distribution models are widely used by ecologists to estimate the relationship between environmental predictors and species presence and abundance records. In this paper, we use compiled faunal assemblage records from archaeological sites located across southwest Asia and southeast Europe to estimate and to compare the biogeography of ancient wild and early domestic cattle (Bos primigenius and Bos taurus). We estimate the contribution of multiple environmental parameters on the explanation of variation in abundance of cattle remains from archaeological sites, and find that annual precipitation and maximum annual temperature are significant predictors of abundance. We then formulate, test, and confirm a hypothesis that states the process of cattle domestication involves a change in the types of environmental ranges in which cattle exploitation occurred by applying a species distribution model to presence-only data of wild and domestic cattle. Our results show that there is an expansion of cattle rearing in more temperate environments, which is a defining characteristic of the European early Neolithic. [ABSTRACT FROM AUTHOR]

The melting of the Scandinavian Ice-Sheet in the early Holocene allowed humans to populate the northernmost parts of Europe. Recent excavations of archaeological sites on the riverbank, floodplain and kame terraces of the River Rena, southeast Norway have defined periods of human occupation in riverside environments, which became ice-free during the last deglaciation. In this paper, we extend the scope of previous archaeological work by examining the sedimentology and chronology of five riverside sedimentary sequences along the River Rena. Our aims were to reconstruct the Holocene evolution of part of the river, and determine whether changes in Holocene settlement patterns might be linked to changes in river evolution and/or climate. Results show: (1) widespread draining of the kame terraces of the River Rena occurred shortly before the first consistent human settlement in the area began c. 8 ka BP; (2) human settlement was maintained until the present day, except during a period of previously undocumented abandonment between c. 4 and 3 ka BP, associated with a sustained period of high river discharge. We link the establishment of first undisputable settlement to reduced water levels as glaciers retreated upstream during a 'warmer' phase of the early Holocene, shortly after the 8.2 ka climatic downturn event. The most recent abandonment of the riverbank settlements 4-3 ka BP occurred during the last phase of glacier advance in the River Rena region, which has been linked to the Europe-wide late- Holocene Thermal Decline (Neoglacial) downturn in climate. [ABSTRACT FROM AUTHOR]

Modern proxy-calibration studies are a powerful tool for paleoecological interpretation. This paper analyzes the relationships among modern pollen rain, vegetation and altitude in the central Pyrenees, where several paleo-palynological studies have been developed, but a modern analog survey is still unavailable. The work analyzes the pollen content of moss polsters from different vegetation communities along an altitudinal transect, as well as the flora and vegetation using the Braun-Blanquet system. DCCA showed that altitude satisfactorily explains both vegetation (r2 = 0.988) and pollen (r2 = 0.841) gradients. Besides the complexity of pollen-vegetation relationships, some regularities were found to be useful for paleoecological and paleoenvironmental interpretation. In general, altitudinal vegetation and pollen patterns show similarities, but pollen belts and boundaries are less well defined, likely because of the homogenizing effect of upward wind transport. Palynological differentiation of montane from subalpine/alpine belts is straightforward from the trends of the more significant pollen types, mainly the low-altitude deciduous trees and the high-mountain herbs. Palynological differences between subalpine and alpine belts, which boundary coincides with the treeline, are more subtle and need quantitative criteria and complementary proxies. From an individual point of view, four main groups of pollen were distinguished, in relation to their usefulness as vegetation and altitudinal indicators: (1) very good indicators, (2) good indicators, (3) non indicators, and (4) allochthonous pollen types. The first two groups resulted to be useful as indicator taxa for modern analogs for paleovegetational and paleoaltitudinal reconstruction, while the latter two groups should be interpreted with caution in paleoenvironmental studies. [ABSTRACT FROM AUTHOR]

Quantitative reconstruction of past vegetation is one of the primary goals in Quaternary palynology and palaeoecology but still remains difficult. This paper proposes a model, REVEALS, that estimates regional vegetation composition using pollen from ‘large lakes’ that have small site-to-site variations of pollen assemblages even if vegetation is highly heterogeneous. Once these data have been used to quantify regional vegetation composition within 104-105 km², background pollen, one of the parameters crucial for vegetation reconstruction, can be estimated for smaller-sized sites, and incorporated into the Landscape Reconstruction Algorithm (LRA), a multistep framework for quantitative reconstruction of vegetation in smaller areas (≤/104 ha). Simulations using the POLLSCAPE modelling show that REVEALS can provide accurate estimates of regional vegetation composition in various landscapes and under different atmospheric conditions. If pollen assemblages from lakes that are much smaller than ‘large lakes’ are used, estimates of regional vegetation at individual sites could be significantly different from the expected values, and their site-to-site variation could be large. However, when pollen data from multiple lakes ≥100-500 ha in size are available, REVEALS can provide accurate estimates of the regional vegetation with relatively small standard errors. Quantitative reconstruction of regional landscape and vegetation change will be critical for testing some of the controversial hypotheses and concepts in global change and conservation research, such as the impacts of agricultural activities on global climate over the last 8000 years and the open-woodland hypothesis in northern Europe in the early Holocene. [ABSTRACT FROM AUTHOR]

This paper examines variability in surface climate and the relationship with two circulation indices using recently produced 200-250 year long European daily and monthly climatic series. Assessments are made of the influence of circulation indices (zonal over western Europe and average pressure over central Europe) on regional temperature, precipitation and drought series for northern and central Europe. Changes in the circulation are shown to be very important during the winter in northern Europe, but only over western and central Europe in summer. Circulation indices in winter, however, only explain up to 25% of surface-climate variability and, except for the British Isles, do not explain any decadal and longer timescale variability in summer. Extreme temperatures and growing-season and frost-season durations and degree-day series are calculated for four sites (Central England, Stockholm, Uppsala and St. Petersburg). Degree-day counts are shown to be very strongly correlated (r > 0.9) to average extended summer ('growing' season, May to September) and extended winter ('frost' season, October to April) temperatures. Durations of the growing and frost seasons are only weakly correlated (r ∼ 0.2-0.4) with the appropriate extended seasonal temperatures or degree-day counts. Warmer growing/frost seasons, therefore, need not necessarily be longer/shorter. Counts of extremely warm days in each year are more highly correlated with the growing-season mean temperature than with coldseason temperature. Similarly, counts of extremely cold days in each year are more highly correlated with cold-season temperature than with growing-season temperature. Both the growing-season temperature and the corresponding degree-day counts clearly show warmer temperatures over all series in Fennoscandia before 1860. Over central Europe, and for the Central England temperature series, growing seasons now are of similar warmth to those before 1860. Annually averaged temperatures across the three regions indicate long-term warming which is, however, almost entirely the result of warming during the October to April period. [ABSTRACT FROM AUTHOR]

In this paper an attempt is made to reconstruct air temperature variations in winter (December, January and February) from 2500 documentary data over the period ad 750–1300 for a region comprising the Benelux countries, eastern France, western Germany, Switzerland and northern Italy. Anomalous (warm and cold) winters were classified on the basis of proxy information on frost, freezing of water bodies, duration of snowcover and untimely activity of vegetation using semiquantitative indices. For the most severe winters during the ‘Medieval Warm Period’ (MWP) as well as for the outstanding warm and dry winter ad 1289/90, possible analogue cases from the last 300 years are considered, analysed, synoptically interpreted and compared with each other. It is concluded that severe winters were somewhat less frequent and less extreme during the MWP, ad 900–1300, than in the ninth century and from 1300 to 1900. Mean air temperatures for 30 year. periods were estimated from linear regression models including indices and instrumental measurements. From ad 1090 to 1179 winter temperatures were at the level of the ‘Little Ice Age’ (LIA). From ad 1180 to 1299 they were at that of the twentieth century. The warm and stable winter climate in the thirteenth century supported subtropical plants such as olive trees in the Po valley (northern Italy) and fig trees around Cologne (Germany). The period ad 1300– 1329 which marks the transition to the LIA was 1°C colder. It is concluded that the 1961–90 level of winter temperatures in western central Europe is still within the threshold of natural variability of the last thousand years, albeit at its upper boundary. [ABSTRACT FROM AUTHOR]

While it is acknowledged that an incorrect age datum was used to construct the depth–age relationship for the lower part of the core in question, the conclusions of the paper, which related to salinity changes of the last 10 000 years, are unaffected. [ABSTRACT FROM AUTHOR]