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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]

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]

How do welfare state policies affect the political support for environmental action of economically vulnerable social groups? Two competing hypotheses can be delineated. On the one hand, a synergy logic would imply that welfare state generosity is associated with higher support for environmental action among economically vulnerable groups due to the insecurity reducing effects of the welfare state. On the other hand, a crowding-out logic would suggest that welfare state generosity is associated with lower support for other policy priorities like environmental action. We test these two hypotheses using 2019 Eurobarometer survey data and country-level indicators of welfare state generosity in 22 European countries. We find that the working class and the elderly are particularly opposed to individual and national environmental action and that the welfare state plays a complex moderating role. Consistent with a synergy logic, welfare state generosity increases pro-environmental behaviour among the working class, but its association with more positive attitudes towards national environmental policies is less strong. Consistent with a crowding-out logic, the elderly appear less likely to behave in environmentally friendly ways if retirement benefits are high. To explore the mechanisms behind this association, we show that the working class who struggle to pay their bills are most opposed to environmental action. Overall, economic insecurities are key obstacles for support of environmental actions and the effects of the welfare state depend both on which social group is concerned and whether individual behaviour versus policy preferences are considered. [ABSTRACT FROM AUTHOR]

Palaeoecological records provide a rich source of information to explore how plant distribution ranges respond to climate changes, but their use is complicated by the fact that, especially when based on pollen data, they are often spatially too inaccurate to reliably determine past range limits. To solve this problem, we focus on hazel (Corylus avellana), a tree species with large and heavy fruits (nuts), which provide firm evidence of the local occurrence of species in the past. We combine the fossil nut records of hazel from Fennoscandia, map its maximum distribution range during the Holocene thermal maximum (HTM) and compare the fossil record with the Holocene hazel range shift as simulated by the LPJ-GUESS dynamic vegetation model. The results show that the current northern range limit of hazel in central and eastern Fennoscandia is constrained by too short growing seasons and too long and cold winters and demonstrate that the species responded to the HTM warming of about 2.5°C (relative to the present) by shifting its range limit up to 63–64°N, reached a rough equilibrium with the HTM climatic conditions and retreated from there to about 60°N during the last 4000 years in response to the late-Holocene cooling. Thus, the projected future warming of about 2.5°C would reverse the long-term southward retraction of species’ northern range limit in Europe and is likely to lead to hazel being a common, regeneratively reproductive species up to 63–64°N. In addition to the accuracy of the projected warming, the likelihood of this scenario will depend on inter-specific competition with other tree taxa and the potential of hazel to migrate and its population to grow in balance with the warming. In general, the range dynamics from the HTM to the present suggest a tight climatic control over hazel’s range limit in Fennoscandia. [ABSTRACT FROM AUTHOR]

Combining nine tree growth proxies from four sites, from the west coast of Norway to the Kola Peninsula of NW Russia, provides a well replicated (> 100 annual measurements per year) mean index of tree growth over the last 1200 years that represents the growth of much of the northern pine timberline forests of northern Fennoscandia. The simple mean of the nine series, z-scored over their common period, correlates strongly with mean June to August temperature averaged over this region (r = 0.81), allowing reconstructions of summer temperature based on regression and variance scaling. The reconstructions correlate significantly with gridded summer temperatures across the whole of Fennoscandia, extending north across Svalbard and south into Denmark. Uncertainty in the reconstructions is estimated by combining the uncertainty in mean tree growth with the uncertainty in the regression models. Over the last seven centuries the uncertainty is < 4.5% higher than in the 20th century, and reaches a maximum of 12% above recent levels during the 10th century. The results suggest that the 20th century was the warmest of the last 1200 years, but that it was not significantly different from the 11th century. The coldest century was the 17th. The impact of volcanic eruptions is clear, and a delayed recovery from pairs or multiple eruptions suggests the presence of some positive feedback mechanism. There is no clear and consistent link between northern Fennoscandian summer temperatures and solar forcing. [ABSTRACT FROM AUTHOR]

Climate change and human activities in Europe have altered erosion and riverine sediment transport for thousands of years. The Danube River basin, the second largest watershed in Europe, provides a unique study area to examine these impacts on fluvial discharge through available reconstructed climate data during the ‘Little Ice Age’ cold interval, as well as documented timing of deforestation and large dam emplacement. Suspended sediment flux of the Danube watershed and its variability in response to both climatic adjustments and human influences is analyzed at the sub-basin scale using a numerical modeling approach (HydroTrend 3.0). The system is examined over three time periods under conditions corresponding to: (1) modern day, (2) pre-dam and (3) the ‘Little Ice Age’. Modeled results indicate that modern-day suspended sediment flux is approximately 60% and 80% lower than that simulated under pre-dam and ‘Little Ice Age’ conditions, respectively. Disregarding the effects of modern-day dams, sediment flux has decreased 46% since the ‘Little Ice Age’, largely due to declining rates of deforestation since the mid to late twentieth century. High-resolution (decadal) analyses based solely on climate change, i.e. assuming no human impact, suggest that suspended sediment flux should be approximately 5% higher today than during the ‘Little Ice Age’, despite a 10% decrease in water discharge.This supports the view that human influence is the dominant forcing agent in modifying, and even reversing, natural processes on the Earth’s surface. Results also suggest that a 4°C increase in average European annual temperatures, as predicted by the Intergovernmental Panel on Climate Change for the end of this century, could result in increased sediment flux by 16–63% in individual basins. [ABSTRACT FROM AUTHOR]

Much research on the discursive construction of Europe in national news media has quantitatively focused on the presence of 'EU topics'. The more frequently EU topics appear, the better the breeding-ground for a sense of European community, it is argued. This article tackles the question of a European identity from a different angle. Guided by theories on collective identity and power, and utilizing qualitative discourse analysis of the reporting on climate change in a tabloid newspaper and public service television news in Sweden, this article discerns a budding European political identity, discursively embedded and 'hidden' in the reporting as the natural order of things. When turned into common-sense knowledge, the European realm as a representative of 'Us' is accorded spontaneous legitimacy as a relevant political power in the making of meaning on climate change. [ABSTRACT FROM AUTHOR]

The increasing interconnectedness of the world that characterizes the process of globalization compels us to interlink local, national, and transnational phenomena, such as environmental risks, in both journalistic and academic discourse. Among environmental risks of global scope climate change is probably the one receiving the most attention at present, not least in the media. Globalization notwithstanding, national media are still dominated by a national logic in the presentation of news, and tensions arise between this media logic and the transnational character of environmental risks that call for a collective responsibility transcending the borders of the nation-states. This article presents results from studies of the construction of global climate change in three Swedish newspapers. It discusses the media's attribution of responsibility for collective action along an axis ranging from local to national to transnational, and highlights the media's reluctance to display any kind of scientific uncertainty that would undermine the demand for collective action. The results underline the media's responsiveness to the political setting in which they operate and the growing relevance of the transnational political realm of Europe for the construction of news frames on global climate change in European national media. [ABSTRACT FROM AUTHOR]

The Global Pollen Database is an example of a successful data synthesis effort that has uses for biogeographical and climate change studies. Results are of interest in many fields of physical geography. Continental-scale maps of past conditions have been used in data-model comparison studies. Time series, developed by averaging quantitative reconstructions from many sites, have indicated that millennial-scale climate variability has affected the vegetation of Europe and North America during the Holocene. Major transitions in the vegetation of Europe and North America occurred at the same time, suggesting the overriding climate effect on the vegetation of both continents. The database can also be used to test biogeographical hypotheses, as several examples illustrate, without the need for collecting new data. Hundreds of studies over the past 50 years show that pollen analysis is more precise than frequently acknowledged: vegetation responds rapidly to climate variations, changes in vegetation are spatially coherent and the taxonomic resolution available in the database is greater than frequently acknowledged. The availability of a public, freely available database enables different analyses to be performed on the same data, thereby ensuring that results are not dependent on methodology. [ABSTRACT FROM AUTHOR]

Periglacial aeolian sand sheets and dunes of the last glacial cover extensive areas of northwest and central Europe. Four sedimentary facies have been described that could be related to fluvio-aeolian and cryogenic processes, moisture content of the depositional surface and surface morphology. Factors that favoured sand-sheet and low-dune formation were the abundance of unconsolidated sediments, absence of topographic barriers, sparseness of vegetation cover and the high ratio of wind energy to sand availability. Three phases of prominent aeolian sand deposition have been distinguished from the Last Glacial Maximum to the beginning of the Holocene. Phase I (c. 28-18 ka cal B.P.) with predominant fluvio-aeolian deposition was related to permafrost conditions of the Last Glacial Maximum. Phase II (c. 18-14 cal B.P.) represents the major period of sand-sheet or coversand formation at the waning stage of the last glacial (Late Pleniglacial and early Lateglacial). Phase III (c. 13-10 cal B.P.) with more localized deposition occurred in the later part of the Younger Dryas and early Holocene. It is stressed that the aeolian phases do not strictly coincide with glacial or stadial conditions. Climatic aridity, limited vegetation cover and delayed responses of the aeolian environment to climate change determine the timing of the aeolian phases. [ABSTRACT FROM AUTHOR]

Fluctuations in Holocene atmospheric radiocarbon concentrations have been shown to be due to variations in solar activity. Analyses of both [sup 10]Be and [sup 14]C nuclides confirm that production-rate changes during the Holocene were largely modulated by solar activity. Analyses of peat samples from two intact European ombrotrophic bogs show that climatic deteriorations during the 'Little Ice Age' are associated with transitions to increasing atmospheric [sup 14]C content due to greater [sup 14]C production. Both ombrotrophic mires, which are positioned c. 800 km apart, register reactions to globally recorded [sup 14]C fluctuations between AD 1449 and 1464 and an almost identical reaction between AD 1601 and 1604. [ABSTRACT FROM AUTHOR]