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This paper reflects on the extensive literature on environmental sustainability that has been produced over the last two decades, and proposes a new approach for environmental policy that goes beyond the cost-benefit analysis that has proved so difficult to implement for non-marginal environmental issues. This approach combines the Safe Minimum Standard approach, which was proposed many years ago, with the concepts of environmental functions and ecosystem goods and services, which have been developed much more recently. It is shown that this approach provides the basis for a robust calculation of sustainability across different environmental themes, following which a ‘sustainability gap’, showing the extent to which this standard is not being met, may be computed. This gap may be expressed in both physical and monetary terms, which permits the formulation of sustainability performance in a scientifically robust, easily communicable indicator that may be compared with GDP. While there appear to be no insurmountable scientific or practical obstacles to the full operationalization of this approach, it remains to be seen whether human societies are sufficiently concerned about the implications of continuing environmental unsustainability to make the resources available for such operationalization, and to enact the policies to allow the sustainability standards to be met. [ABSTRACT FROM PUBLISHER]

The recent rapid mass loss of mountain glaciers in response to climate warming has been reported for high and low latitudes all over the Earth. The paper analyses and discusses the recent evolution of a representative glacierized group within the Italian Alps, the Piazzi—Dosdè, where small glaciers are experiencing considerable retreat and shrinking. We analysed aerial photos to calculate area and geometry changes in the time window 1954—2003, and glaciological and geomorphological surveys were also performed. The estimated area change during 1954—2003 was —3.97 km2 (—51% of the area coverage in 1954). Area reduction increased more recently: area change during 1991—2003 (12 years) was —1.74 km2, against —0.67 km2 during 1981—1991 (10 years), and —1.57 km 2 during 1954—1981 (27 years). Moreover, analysis of the most recent orthophotos acquired during the summer of 2003 under exceptional conditions (i.e. total absence of snow cover) allowed observation and mapping of changes affecting glacier shape and morphology, including growing rock outcrops, tongue separations, formation of proglacial lakes, increasing supraglacial debris and collapse structures. Such processes cause positive feedbacks that accelerate further glacier disintegration once they appear. From a geodynamical perspective, the Dosdè Piazzi is now experiencing transition from a glacial system to a paraglacial one; areas where in the past the shaping and driving factors were glaciers are now subject to the action of melting water, slope evolution and periglacial processes. [ABSTRACT FROM PUBLISHER]

Anthropogenic climate change represents a deep and credible threat to human society in a variety of ways. The particular shape of this threat is historically novel and commonly associated with experiences of fear mixed with both guilt and impotence. What is the moral significance of this fear in a faithful Christian response to anthropogenic climate change? How is the Christian ethicist to locate fears of climate change? How can such fears become constructive for, rather than destructive of, ethical thought? Taking Hans Urs von Balthasar’s short text, The Christian and Anxiety, as a dialogue partner, this paper will explore healthy and unhealthy modes of alarm in the face of an increasingly disrupted climate. Balthasar argues that Christ’s own anxiety during his passion liberates believers from certain kinds of fear, and then opens the creative possibility of entering into the fears of one’s neighbour as an expression of love. [ABSTRACT FROM PUBLISHER]

Empirical evidence of our changing climate is frequently interpreted through the lens of either optimism or pessimism. In tandem with this, ethical responses can oscillate from myopic ‘business as usual’ to misanthropic ‘lifeboat ethics’. In this paper I argue that these are inadequate and unworthy positions from which to begin in Christian ethics. The question of sharing the burdens of climate-change mitigation and adaptation is the crucial task facing the world community. The development of the burden-sharing rules—sector based as well as country based—since the Kyoto agreement will be evaluated from the perspective of three theological ethical principles: justice, solidarity and subsidiarity. Lastly I suggest that creation serves as a ground for developing shared perspectives in the ethics of environmental questions in the context of intercultural and interfaith dialogue. [ABSTRACT FROM PUBLISHER]

This paper argues that given the importance of joining together local and global aspects of climate change, individual conscience needs to be complemented by critical consideration of collective forms of conscience. Evidence for the existence of such collective forms as relevant to climate debates can be found in public reactions to email leaks on climate science, dubbed ‘Climategate’ in the processes leading up to the United Nations Summit on Climate Change, COP-15. In critical engagement with Emile Durkheim’s conscience collective and Bernard Häring’s reciprocal consciences, I argue for collective conscience to be used as a heuristic tool in order to analyse both weaknesses in collective responsibility and appropriate actions of communities at local, national or international levels. I suggest that such an approach critically engages with more general notions such as the role of solidarity in public debate that both develops and critiques Jürgen Habermas’s more recent work opening up a religious voice in the public domain. Using an experiential case study from the Massai tribe, I intend to show just one way in which collective conscience might be expressed when faced with the problems associated with climate change. [ABSTRACT FROM PUBLISHER]

The paper argues, first, that the range of problems confronting humanity constitutes a global emergency; next, that this cannot be addressed by moral exhortation but by the building of ‘arks’; finally, that community, cultivation of the virtues, and place may be considered key aspects of such ark building. [ABSTRACT FROM PUBLISHER]

In Mediterranean and north-African regions, cultural trajectories have shown trends sometimes coincident with climatic changes. The mid Holocene was a period of intense changes in climate, and in environmental and cultural systems. This paper reports pollen and charcoal studies from these areas aiming at presenting how impressive cultural changes frequently coincided with critical climate oscillations. Three of the main dry events of key relevance for climatic—cultural changes were selected to discuss this topic: c. 8200 cal. yr BP, c. 6000 cal. yr BP, and c. 4200 cal. yr BP. Five examples from on-site case studies were reported: (1) Wadi Teshuinat area (Fezzan, Libya, Central Sahara); (2) Benzù cave (Ceuta mountains, Spain, NW Africa); (3) La Vaquera Cave (Central System, Spain); (4) Terramara di Montale (Po Plain, Northern Italy); (5) Arslantepe (Eastern Anatolia, Turkey). Their archaeobotanical record helps to recognise and date human presence and activity in different territories. In these examples, anthropogenic signals and comparisons with other sites could be useful to distinguish climate signal from human impact in pollen records. Charcoals are evidence of human activity in cases which are not shown by pollen. Overexploitation of thinned plant resources, including overgrazing, accelerated the evolution towards xeric conditions during drying climatic phases. Humans enforced the aridity crisis and enhanced its signal in palaeoclimatic records. Sometimes, changing exploitation strategies and movements led to the onset of new cultures. Nevertheless, the onset and decline of a culture are very different critical phases, and different agents must have been involved in their occurrence. The Bronze Age marked the environment more than the Neolithic, probably because there is a relation between improvements in knowledge, cultural changes and the evolution of complex forms of land exploitation. [ABSTRACT FROM AUTHOR]

This paper provides a synthesis of available palynological data from central Mediterranean lacustrine records, studying the causes of the important vegetation changes which occurred in the mid Holocene. They are illustrated by seven well-dated records, lakes Accesa, Mezzano, Vico, and Pergusa in Italy, Maliq, Voulkaria and Malo J. in the Balkans. A good tool for disentangling climate change and human impact is the combined interpretation of pollen percentage and concentration/influx data. Pollen concentration/influx drops are an indication of increased erosion in the catchment, mainly ascribable to forest reduction. There is no doubt that major synchronous changes could not have been caused by humans alone. Many southern European records show substantial differences between early- and late-Holocene vegetation, suggesting a general evolution from wetter to drier climatic conditions, in agreement with arid phases recognised by other, independent palaeoclimatic methods. Other pollen records show a different trend. The role of changing seasonality seems important for this region of the Mediterranean. Precipitation seasonality increased during the early to mid Holocene with winter precipitation attaining a maximum, and summer precipitation a minimum. At least three rapid climate events with changes in plant biomass are in evidence: an abrupt and short change around 8200 yr BP, another one centred around 6000 yr BP, and one soon after 3000 yr BP. From the beginning of the Bronze Age (c. 4400 yr BP in this region) human impact overlapped with a climate change, probably bipartite, towards dryness. Our results show that this aridification trend began around 8000 yr BP, and culminated around 4000 yr BP. [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]

Postglacial expansion of deciduous oak woodlands of the Zagros-Anti-Taurus Mountains, a major biome of the Near East, was delayed until the middle Holocene at ~6300 cal. yr BP. The current hypotheses explain this delay as a consequence of a regional aridity during the early Holocene, slow migration rates of forest trees, and/or a long history of land use and agro-pastoralism in this region. In the present paper, support is given to a hypothesis that suggests different precipitation seasonalities during the early Holocene compared with the late Holocene. The oak species of the Zagros-Anti-Taurus Mts, particularly Quercus brantii Lindl., are strongly dependent on spring precipitation for regeneration and are sensitive to a long dry season. Detailed analysis of modern atmospheric circulation patterns in SW Asia during the late spring suggests that the Indian Summer Monsoon (ISM) intensification can modify the amount of late spring and/or early summer rainfall in western/northwestern Iran and eastern Anatolia, which could in turn have controlled the development of the Zagros-Anti-Taurus deciduous oak woodlands. During the early Holocene, the northwestward shift of the Inter-Tropical Convergence Zone (ITCZ) could have displaced the subtropical anticyclonic belt or associated high pressure ridges to the northwest. The latter could, in turn, have prevented the southeastward penetration of low pressure systems originating from the North Atlantic and Black Sea regions. Such atmospheric configuration could have reduced or eliminated the spring precipitation creating a typical Mediterranean continental climate characterized by winter-dominated precipitation. This scenario highlights the complexity of biome response to climate system interactions in transitional climatic and biogeographical regions. [ABSTRACT FROM AUTHOR]

Discharge from the largest karst spring in north China, the Niangziguan Springs, has been declining since the 1950s. This paper examines the response of these springs to climatic change and anthropogenic influence by attempting a model-based discrimination between phases in the stream discharge record. In Niangziguan Springs Basin, the exploitation of karst groundwater began in 1979. Accordingly, the spring discharge data were divided into two phases: pre-1979 and post-1979. In the first phase (1957-78) the spring discharge was believed to be affected solely by climate change, and in the second phase (1979-2007) the spring discharge was influenced by both climate change and human activities. Using grey system theory, a discharge model was estimated for the first phase. Extrapolating the model, we obtained a projection of the spring discharge during the second phase. Using a water balance calculation, we discerned the respective effects of climate change and human activities on depletion of spring discharge for the second phase. The results show that the contribution of climate change to depletion of Niangziguan Springs is 2.30m3/s and the contribution of anthropogenic activities ranges from 1.89 to 2.90 m3/s, although this assumes a constant for the climate change effect. Accordingly, the anthropogenic effects have been approaching and surpassing the effects of climate change during the second phase. With respect to the impact of human activities on spring discharge, groundwater abstraction accounts for only about 34-52% of the declines; 48-66% of the declines are related to other human activities, such as dewatering from coal mining, dam building and deforestation. [ABSTRACT FROM AUTHOR]

The use of small-scale generation based on disparate new and renewable technologies is becoming more prevalent due to the imperative to reduce greenhouse gas emissions that are thought to be the chief cause of climate change. As penetration of these distributed elements increases, displacing central generation, there is a growing need to understand the composite behaviour of groups of Distributed Generation (DG) devices, also known as Virtual Power Plants (VPPs). This paper presents an overview of the mathematical modelling of the VPP leading to the development of a user-friendly tool that can be used as a power system engineering teaching aid to demonstrate the characteristics of VPPs. [ABSTRACT FROM AUTHOR]

Measurement is at the heart of our modern technological world, supporting trade, industry and science and underpinning the regulatory framework that helps maintain and improve our quality of life in areas as diverse as public health and safety, climate change, and sport and leisure. Unlike a large proportion of the millions of measurements made each day, those relating to things we can 'see', such as lamps and lighting, are not based only on physical parameters, but must also take account of the human visual responses. This paper explores the shortcomings in our current measurement systems for light and lighting, and highlights where further research is needed in order to understand more fully the ways in which light affects us. The latest advances in instrumentation and data analysis techniques are also reviewed and the potential consequences for measurements of lighting and glazing are considered. [ABSTRACT FROM AUTHOR]

This paper describes the application of a hydrogeomorphological numerical model (CAESAR) to simulate, at hourly time steps, changes in the hydrological and sediment regime of the Petit lac d'Annecy catchment. The outputs of the model were validated in three ways. In the short term (∼5 years), water discharge outputs were compared against observed instrumental data. Over the longer term, modelled sediment discharge (AD 1825-2005) was compared with proxies for detrital sediment influx (environmental magnetism) and accumulation rates discerned from a 210Pb chronology for the lake sediments. Finally, spatial validation of the modelled erosion and deposition of sediment was undertaken by comparison with a field and remotely sensed survey of catchment geomorphology. The results suggest that while minor perturbations in forest cover during the last 180 years have partially conditioned the response of the sediment system, the bulk of modelled sediment discharge and particularly the peaks in sediment discharge were controlled by flood duration and magnitude, which in turn is driven by precipitation (storms/floods) and snowmelt. Basin geometry and geomorphology of each subcatchment (Ire and Tamie) were also important in producing differences in the modelled sediment discharge. In essence, these differences were a function of sediment accommodation space and the ability of each system to store and release sediments. Modelled sediment discharge and χpara (lake sediments) display similar histories, and thus are both interpreted as reflecting variations in detrital sediment supply. Intriguingly the style of modelled sediment discharge from the Ire, a confined mountain torrent, displays a greater similarity to and perhaps dominates the lake sediment record. These results provide partial validation of the CAESAR model and indicate that perhaps in the future it may be used as an exploratory and predictive tool in determining the impact of changes in climate, meteorology and land use on lake-catchment systems. [ABSTRACT FROM AUTHOR]

This paper presents the anthracological results of Cova de la Guineu. This cave, which is located at the NE of the Iberian Peninsula, has provided charcoal samples from the early Neolithic to the Iberian period enabling the identification of different phases on the basis of flora assemblage interpretation. The results show how Mediterranean forests have been present since the early Holocene stages. At the early phases of the sequence the assemblage records dominant meso-screrophyllous taxa (deciduous Quercus, Taxus baccata), then thermophilous taxa (evergreen Quercus) spread, and finally a late phase of transformation dominated by thermophilous and heliophilous taxa (Mediterranean Pinus). The interpretation and discussion deals with the development and transformation of primary and secondary forests due to human disturbances and climatic variations. The anthracological record from Cova de la Guineu suggests that both elements were important and define the evolution of vegetation during the Holocene in the region. [ABSTRACT FROM AUTHOR]

Water erosion is the most destructive erosion type worldwide, causing serious land degradation and environmental deterioration. Against a background of climate change and accelerated human activities, changes in natural rainfall regimes have taken place and will be expected to become more pronounced in future decades. Long-term shifts may challenge the existing cultivation systems worldwide and eventually alter the spatiotemporal patterns of land use and topography. Meanwhile, specific features of soil crusting/sealing, plant litter and its decomposition, and antecedent soil moisture content (ASMC) will accompany rainfall variability. All these changes will increase pressures on soil erosion and hydrological processes, making accurate erosion prediction and control more difficult. An improved knowledge and understanding of this issue, therefore, is essential for dealing with the forthcoming challenges regarding soil and water conservation practices. In this paper, the characteristics of changes in natural rainfall, its role on terrestrial ecosystems, the challenges, and its effect on surface water erosion dynamics are elaborated and discussed. The major priorities for future research are also highlighted, and it is hoped that this will promote a better understanding of water erosion processes and related hydrological issues. [ABSTRACT FROM AUTHOR]

The steep outlet glaciers of Jostedalsbreen, western Norway, are good examples of sensitively reacting maritime mountain glaciers. Their changes in length, frontal position and lower tongue's morphology during the past 20 years have been well documented. At first they experienced a strong frontal advance. After AD 2000 glacier behaviour was dominated by a strong frontal retreat, in some cases causing a separation of the lowermost glacier tongue. In this paper, the glacier length changes are presented both visually and numerically, supplemented by mass balance and meteorological data. The glacier behaviour is interpreted and its causes are discussed. Whereas the factors controlling the advance during the 1990s seem clear, the interpretation of the most recent retreat still leaves some uncertainties. The actual glacier front behaviour cannot fully be related to the mass balance data. Terminus response times and relations between individual mass balance and meteorological parameters have changed. Some hypotheses are given, including disturbance of the 'normal' mass transfer and dynamical response of the glacier front because of excessive ablation on the lowermost glacier tongues and summer back melting. These findings underline the sensitivity of maritime glaciers to climate changes. The empirical findings need to be taken into account in the interpretation of recent glacier length changes and their future modelling. [ABSTRACT FROM AUTHOR]

The mixed semi-evergreen forests in lowland central equatorial Africa can contain many elements of secondary vegetation. This raises the question of what factors have determined the current forest composition in this region. Is this forest in the process of succession after natural climatic variation and/or anthropogenic disturbances in the past, or is it a stable forest type? This paper presents a multiproxy palaeoecological analysis of a sedimentary sequence taken from a small sedimentary basin located in logged semi-evergreen lowland forest in northern Congo-Brazzaville which addresses these questions. Analyses undertaken included fossil pollen, geochemical and microscopic charcoal. Geochemical results were interpreted as a proxy for rainfall, and showed that northern Congo has experienced changes in rainfall during the past 2580 years, while microscopic charcoal concentrations indicated increased burning from approximately 1240 cal. yr BP to the present. Analysis of the fossil pollen assemblages showed that although light-demanding taxa were a major constituent of this forest throughout the sequence, shade-tolerant taxa were more abundant in the forest prior to 1345 cal. yr BP. Increases in aridity and/or droughts after 1345 cal. yr BP, and an increase in fire after 1240 cal. yr BP resulted in a semievergreen forest with abundant pioneers that persisted with minor changes in composition during the last 900 years, even during a period of increased rainfall from 400 to 100 cal. yr BP. These data may guide conservation policy by predicting potential consequences of future climate change and the impact of logging. [ABSTRACT FROM AUTHOR]

In the coastal lowlands of Mozambique, an expansion of savannas at the cost of forests has been attributed to anthropogenic influence. There are few investigations that have studied vegetation dynamics over the long term. Pollen analysis from two sedimentary cores in the Chibuene area, 7 km south of Vilanculos presented in this paper show that the coastal area 1600 years ago consisted of a mosaic of forests, Miombo woodlands and grasslands. The data also show that the area supported extensive forests in the past until AD 1400-1600 when the forests declined dramatically. Changing settlement patterns, as suggested from archaeological excavations, cannot be correlated with the forest decline and the charcoal abundance, in the sedimentary cores does not suggest an intensification of farming. Instead the decline of forests appears to be temporally correlated with a prolonged period of repeated dry spells associated with the 'Little Ice Age', which caused a shift in vegetation whereby typical forest species as Trema, Celtis and Moraceae were outcompeted on account of the droughts. This study challenges rooted assumptions about the cause of decline of forests in the coastal region. It also suggests that the forest fragments present on the Mozambique coast today are naturally subject to threat from climatic stress and as such are highly sensitive areas to future climate change. [ABSTRACT FROM AUTHOR]

The article reports on an inquiry on the application by the operators of Stansted Airport, British Aerospace Airbus (BAA), to remove the planning condition that imposed a passenger limit at the airport to 25 million passengers a year. The argument of BAA is the air transport white paper which sets out the strategic framework of the government which called for a balanced and measured approach to the future of air transport.

Recent scientific findings, as presented in the Arctic Climate Impact Assessment (AdA), indicate that climate change in the Arctic is happening now, at a faster rate than elsewhere in the world, and with major implications for peoples of the Arctic (especially indigenous peoples) and the rest of the planet. This paper examines scientific and political representations of Arctic indigenous peoples that have been central to the production and articulation of these claims. ACIA employs novel forms and strategies of representation that reflect changing conceptual models and practices of global change science and depict indigenous peoples as expert, exotic, and at-risk. These portrayals emerge alongside the growing political activism of Arctic indigenous peoples who present themselves as representatives or embodiments of climate change itself as they advocate for climate change mitigation policies. These mutually constitutive forms of representation suggest that scientific ways of seeing the global environment shape and are shaped by the public image and voice of global citizens. Likewise, the authority, credibility, and visibility of Arctic indigenous activists derive, in part, from their status as at-risk experts, a status buttressed by new scientific frameworks and methods that recognize and rely on the local experiences and knowledges of indigenous peoples. Analyses of these relationships linking scientific and political representations of Arctic climate change build upon science and technology studies (STS) scholarship on visualization, challenge conventional notions of globalization, and raise questions about power and accountability in global climate change research. [ABSTRACT FROM AUTHOR]

On the basis of sediment and pollen analyses of a radiocarbon-dated sediment sequence from Lake Joux in the Swiss Jura Mountains (west-central Europe), this paper presents a high-resolution record of lake-level and vegetation changes for the last millennium. The lake-level record makes it possible to determine that lowstands of the water-table dominated at c. AD 1200-1400, and from 1720 onward, with interruptions by short-lived rise events at c. AD 1340 and 1840. Highstands prevailed at c. AD 1100, and around AD 1450, 1550 and 1700. The comparison of the Joux lake-level record with a solar irradiance record based on cosmogenic nucleides supports the hypothesis of a major solar forcing of climate variations in west-central Europe over the last millennium. In agreement with other palaeohydrological records established in Western Europe and in the central North Atlantic Ocean, the Joux lake-level record suggests that, on a multicentennial scale, the period of the 'Little Ice Age' coincided in the European mid-latitudes with wetter climatic conditions, and probably with an increase in summer precipitation. Variations in the hydrological cycle appear to have been associated with changes in the general atmospheric circulation pattern, probably coupled with variations in oceanic circulation and solar activity. The Joux record also points to changes in water resources expected to result from ongoing global warming. Finally, despite the severe climatic conditions which prevail in the Joux Valley, the human impact history at Lake Joux over the last millennium seems to reflect political choices and economic context more than climatic changes. [ABSTRACT FROM AUTHOR]

Frank Oldfield's immense contribution to palaeoenvironmental science is summarized in relation to: pollen analysis, vegetation history and peat stratigraphy; palaeolimnology and 210Pb dating; environmental magnetism, catchment-lake relationships and soil erosional history; multiproxy approaches; PAGES; and editing The Holocene. The tribute includes an introduction to the 14 other papers in this Special Issue, which were inspired in diverse ways by this remarkable scientist. [ABSTRACT FROM AUTHOR]

Abstract: A total of 237 surface soil pollen samples were collected from less disturbed zonal communities, and a new surface pollen data set has been established in northern China. Pollen-climate parameter transfer functions using weighted-averaging regression and calibration partial least squares (WA-PLS) model as a tool to reconstruct past climate changes from pollen data, were tested with this new surface pollen data set. The results of cross validation showed that the method worked very well with precipitation (R = 0.94, R2 jack = 0.89, RMSEPjack = 69 mm, the safe dynamic range of the reconstruction was 40 mm~800 mm) and worked well with temperature (Tann: R = 0.84, R2 jack = 0.71, RMSEPjack = 2.0°C, the safe dynamic range of the reconstruction was -4°C~13°C; MTwa: R = 0.79, R2 jack = 0.63, RMSEPjack = 2.5°C, and the safe dynamic range of the reconstruction was 8°C~26°C), indicating that the surface pollen data set and WA-PLS reconstruction technique in this paper have strong potential for palaeoclimatic reconstruction. [ABSTRACT FROM AUTHOR]

This paper analyses the relationship between field experimentalists and simulation modellers in meteorological research on the one hand, and how this is related to climate change as a common arena of concern on the other. Climate has become the central topic in meteorological research and it is imperative to link specific research problems to climate change in order to receive funding and attract talent. In addition, climate models have become gatekeepers for claims about climate change. Hence, active participation in climate modelling processes is valuable for all parties. Observational data are used in order to develop new components — so-called parameterizations — for the climate models and these novel components therefore emerge as important boundary objects. While they serve different purposes for experimentalists and modellers in terms of translation processes, they also serve to connect these groups and reinforce their mutual dependence. [ABSTRACT FROM AUTHOR]

Large, infrequent fires (LIFs) can have substantial impacts on both ecosystems and the economy. To better understand LIFs and to better predict the effects of human management and climate change on their occurrence, we must first determine the factors that produce them. Here, we review local and regional literature investigating the drivers of LIFs. The emerging conceptual model proposes that ecosystems can be typified based on climatic conditions that determine both fuel moisture and fuel amount. The concept distinguishes three ecosystem types: (1) biomass-rich, rarely dry ecosystems where fuel moisture rather than fuel amount limits LIFs; (2) biomass-poor, at least seasonally dry ecosystems where fuel amount rather than fuel moisture limits LIFs; and (3) biomass-poor, rarely dry ecosystems where both fuel amount and fuel moisture limit the occurrence of LIFs. Our main goal in this paper is to discuss the drivers of LIFs and the three mentioned ecosystem types in a global context. Further, we will discuss the drivers that are not included within the ‘fuels’ versus ‘climate’ discussion. Finally, we will address the question: what kinds of additional information are needed if models predicting LIFs are to be coupled with global climate models? As with all generalizations, there are local deviations and modifications due to processes such as disturbance interaction or human impact. These processes tend to obscure the general patterns of the occurrence of LIFs and are likely to cause much of the observed controversy and confusion in the literature. [ABSTRACT FROM AUTHOR]

Pollen analysis of a 48 m AMS radiocarbon-dated sediment sequence from the Guadiana estuary provides the first record of Lateglacial and Holocene vegetation history in the Algarve province of Portugal. This paper focuses on the record of terrestrial pollen taxa, which document a series of forest expansions and declines during the period 13 000 cal. BP to 1600 cal. BP and provide insights into climate evolution in southwestern Iberia. The main vegetation phases identified in the Guadiana valley are (1) Lateglacial interstadial (Allerød) forest with Quercus and Pinus under a temperate, moist, continental climate; (2) a Younger Dryas forest decline (Quercus) and expansion of pinewoods, xeric scrub and open ground habitats (with Juniperus, Artemisia, Ephedra distachya type, Centaurea scabiosa type) under arid and cold conditions; (3) an early Holocene forest/scrub/open-ground vegetation mosaic developing under a warm, dry and continental climate; (4) a maximum of Quercus forest and thermomediterranean evergreen taxa (Olea, Phillyrea, Pistacia) reflecting a warm, moist oceanic climate between c. 9000 cal. BP and c. 5000 cal. BP; and (5) the expansion of shrublands with Cistaceae and Ericaceae under a drier climatic regime and increasing anthropogenic activity since c. 5000 cal. BP. Holocene episodes of maximum climatic aridity are identified in the record of xerophytic taxa (Juniperus, Artemisia, Ephedra distachya type) centred around 10 200 cal. BP, 7800 cal. BP, 4800 cal. BP, 3100 cal. BP and 1700 cal. BP. Regional comparisons suggest a correlation of arid phases across southern Iberia and northwest Africa, which can be related to abrupt North Atlantic coolings (Bond events). [ABSTRACT FROM AUTHOR]

The paper uses Greenland GISP2 ice core data together with historical documentary information to investigate the nature of climate changes that took place between AD 1270 and 1450 across the North Atlantic region. Detailed Deuterium and deuterium excess time series resolved to c. 8–10 samples per year are used to reconstruct relative changes in Greenland air temperature and past changes in sea surface temperature across the western North Atlantic. The data show that sea surface temperatures during the late thirteenth century and the majority of the fourteenth century were characterized by relatively high-amplitude warming and cooling ‘events’. These changes preceded a marked reduction in the amplitude of the sea surface temperature changes c. 30–40 years before the well-known change in Northern Hemisphere tropospheric circulation characterized by a marked increase in regional storminess that started between c. AD 1400 and 1420. The time interval between AD 1270 and 1450 also appears over Greenland to have featured several short-lived phases of marked air temperature lowering that were rarely ever equalled during succeeding centuries. We believe that the climate changes described here are of considerable importance in understanding climate dynamics of the North Atlantic region since they took place at a time when the North Atlantic Oscillation (NAO) may have been weak. The results also show that the marked change in atmospheric circulation coincident with a significant increase in North Atlantic storminess at c. AD 1400–1420, possibly the biggest such change in the Holocene, took place after the strong perturbations in North Atlantic sea surface temperature (both warming and cooling) described here as well as after several episodes of air temperature lowering over Greenland. [ABSTRACT FROM AUTHOR]

Retention and sequestration of soil organic matter is extremely important for the maintenance of soil structure, agricultural productivity and carbon sequestration. Research in soil organic matter has advanced on many fronts in the last half century. During this time understanding of the factors governing plant litter decomposition has increased considerably resulting in the formulation of process and organism-based models. Remote sensing has been shown to be useful for quickly monitoring stocks of soil organic carbon in the topsoil although much remains to be done to establish its efficacy. Fluxes of soil organic matter in the changing climatic scenarios have been studied though outcomes remain debatable. In this paper an attempt is made to present these various aspects of soil organic matter cohesively. The focus is mainly on litter decomposition, models and monitoring methods, role of soil aggregates and erosion, impact of climate change on long-term dynamics of soil organic matter and impending research themes needing further attention. [ABSTRACT FROM AUTHOR]

Understanding the sediment delivery process at the drainage basin scale remains a challenge in erosion and sedimentation research. In the absence of reliable spatially distributed processbased models for the prediction of sediment transport at the drainage basin scale, area-specific sediment yield (SSY; t km-2 y-1) is often assumed to decrease with increasing drainage basin area (A). As the measurement of A is relatively simple, this assumption is frequently used for prediction of SSY in ungauged basins. However, over the last two decades several studies reported a positive or nonlinear relation between A and SSY. Various authors have suggested diverse explanations for these opposing trends. This paper provides an overview of the different observed trends and summarizes the explanations for each trend. Furthermore, three typical trends are identified to conceptualize the main driving forces of the relation between A and SSY. First of all, it is emphasized that erosion and sediment deposition processes are scale dependent, and going from small (~104km2) a decrease in SSY is observed when drainage density decreases or channel banks are stabilized. Finally, spatial patterns in lithology, land cover, climate or topography can cause SSY to increase or decrease at any basin area and can therefore result in non-linear relations with A. Altogether, with increasing A often first a rise and then a decrease in SSY is observed. The decrease can be absent or can be postponed within a region due to local factors of which lithology, land cover, climate and topography are the most important ones. The large regional, local and even temporal variability in the trend between A and SSY implies that prediction of SSY based on A alone is troublesome and preferably spatially distributed information on land use, climate, lithology, topography and dominant erosion processes is required. [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]

Interpretation of proxy-climate records depends on a thorough understanding of the proxy—climate relationship. Peatland surface wetness records have been interpreted as reflecting changes between cool and/or wet conditions and warm and/or dry conditions. This paper analyses a high-resolution record of reconstructed water-table changes based on testate amoebae analysis in relation to instrumental weather records since AD 1775. Replicate peat records are reconciled by multiple chronological techniques and tuning, and demonstrate that the reconstructions preserve many replicable high-frequency changes. Watertable variability is highly correlated with the total seasonal moisture deficit (precipitation — evapotranspiration, P-E) expressed as the sum of all months with negative P-E. The reconstructed water-table record reflects antecedent periods of 5 or 10 years (maximum r² = 52.4%) and proxy bog surface wetness records can therefore be interpreted as reflecting the length and intensity of the summer water deficit period. Response surfaces of the summer deficit in relation to temperature and precipitation variability support the hypothesis that the summer deficit is determined by summer precipitation in mid-latitude oceanic peatlands and that summer temperature plays a greater but still subsidiary role in higher latitude, continental settings. These relationships apply for all plausible past Holocene climate changes and future twenty-first century climate scenarios. Non-linear responses to longer-term climate states prevent the direct application of a calibration of the reconstructed water-table records to infer quantitative estimates of climate variables. Models that combine peat accumulation, mire growth and hydrological processes are required to undertake this task. [ABSTRACT FROM AUTHOR]

This paper describes an approach that gives an estimate of the reconstructive skill of a proxy-based palaeoclimatological reconstruction. Uncertainties in proxy data are likely to be reflected in variations in reconstructive skill of the proxy-based climatic reconstructions. The method is based on making an ensemble of reconstructions, providing a probability distribution of each reconstruction estimate. The relative breadth of the distribution for a particular reconstructed value should give an indication of the reconstructive skill. The ensemble reconstruction approach draws on the ensemble prediction system as used for operational weather forecasting. The ensemble reconstruction approach is tested using a recent multiproxy reconstruction of the winter North Atlantic Oscillation (NAO) index. It is shown that the ensemble approach provides a representation of the degree of certainty associated with the reconstructed NAO-index values. [ABSTRACT FROM AUTHOR]

This paper describes our recent extraction of ancient DNA (aDNA) from Holocene pollen and discusses the potential of the technique for elucidating timescales of evolutionary change. We show that plastid DNA is recoverable and usable from pollen grains of Scots pine Pinus sylvestris from 10 ka and 100 years ago. Comparison of the ancient sequences with modern sequences, obtained from an extant population, establish a first genetic link between modern and fossil samples of Scots pine, providing a genetic continuity through time. One common haplotype is present in each of the three periods investigated, suggesting that it persisted near the lake throughout the postglacial. The retrieval of aDNA from pollen has major implications for palaeoecology by allowing (i) investigation of population-level dynamics in time and space, and (ii) tracing ancestry of populations and developing phylogenetic trees that include extinct as well as extant taxa. The method should work over the last glacial oscillation, thus giving access to ancestry of populations over a crucial period of time for the understanding of the relationship between speciation and climate change. [ABSTRACT FROM AUTHOR]

The prediction of the impact of anthropogenic land use change on the climate system hinges on the ability to properly model the interaction between the heterogeneous land surface and the atmosphere in global climate models. This paper contains a review of techniques in general use for modeling this interaction in general circulation models (GCMs) that have been used to assess the impact of land use change on climate. The review includes a summary of GCM simulations of land cover change using these techniques, along with a description of the simulated physical mechanisms by which land cover change affects the climate. The vertical extent to which surface heterogeneities retain their individual character is an important consideration for the land-atmosphere coupling, and the description of a recently developed technique that improves this aspect of the coupling is presented. The differences in the simulated climate between this new technique and a technique in general use include the presence of a boundary layer feedback mechanism that is not present in simulations with the standard technique. We postulate that the new technique when implemented in a GCM has the potential to guide an improved understanding of the mechanisms by which anthropogenic land use change affects climate. [ABSTRACT FROM AUTHOR]

River basins in Great Britain and Ireland have been characterized by periods of hillslope and valley floor instability during the Holocene, reflecting sensitivity to both climate change and anthropogenic disturbance. In contrast to climatic controls, which have been relatively well documented, human impacts on and interactions with river basins remain unclear. There is now, however, a growing impetus to elucidate more fully the impact of anthropogenic activity on sediment supply and runoff, given that land-use change is thought to have exacerbated recent flooding in the UK (eg, the 'Millennium' floods of 2000). The aim of this paper is to critically review the significance of Holocene land use on hillslope and valley floor stability in Great Britain and Ireland. The most widely reported impacts of land-use change on geomorphic activity include hillslope erosion and gully development, valley floor alluviation, river channel incision and elevated water tables. In the majority of cases, however, causal relationships are difficult to establish, due primarily to inadequate dating control. Even where geomorphic instability can be linked to land-use change, it is apparent that eroded material is often stored as colluvium, which together with evidence of diachronus hillslope and valley floor instability, raises important questions and identifies uncertainties regarding the dynamics and extent of sediment transfer within river basins. Such uncertainty has important implications for understanding how river basins will behave in response to future environmental change. [ABSTRACT FROM AUTHOR]

This paper reviews recently published literature, most of which was published in Chinese, and searches for regional patterns of Holocene changes useful in depicting global patterns. The Holocene in the Xinjiang region can be divided into three stages: a warming and dry early stage (from 11 ∼ 10 to 8 ∼ 7 ka BP), a warm and wet middle stage (from 8 ∼ 7 to 4.5 ∼ 3 ka BP) and a fluctuating cool and dry late stage (since 4.5 ∼ 3 ka BP). The Holocene in the northern Tibetan Plateau can also be divided into three stages: a warming and wet stage (from 10.5 ∼ 10 to 5 ∼ 4 ka BP), followed by a variable drying and probably warm stage (5 ∼ 4 to 3 ka BP) and ending with a cool and dry stage (since 3 ka BP). In the Inner Mongolian Plateau, the early Holocene (from 10.5 ∼ 9.5 to 8 ∼ 7.5 ka BP) was warming and dry, and a warm and wet climate occurred from 7.5 to 3.5, during which the best time was 6.3–3.8 ka BP; the climate has been variably drying and probably cooling since 3.5 ka BP. In the northwestern part of the Loess Plateau, several Holocene palaeosols have been identified (10–9, 7.5–5, 4–3 and 2.7–2 ka BP) with the 7.5–5 ka BP palaeosol being most strongly expressed. The best-developed palaeosol-equivalent in major valleys is a swamp-wetland facies deposited between 8885 and 3805 14C yr BP under an extremely wet regime. The climate has fluctuated significantly at least three times around a dry and probably cool regime after the swamp-wetland facies-depositional period. Our summary shows that the Holocene Climatic Optimum occurred nearly contemporaneously (8–5 ka BP) at all sites in the Xinjiang region, in the Inner Mongolian Plateau and in the northwestern part of the Loess Plateau. A warming and wet early Holocene (10–8 ka BP) in the northern Tibetan Plateau is most likely related to high effective soil moisture resulting from snow and ice melting. We propose here that the middle Holocene Climatic Optimum (8–5 ka BP) in arid to semi-arid China was primarily a delayed response of the low latitude oceans to high latitude peak insolation (9–8 ka BP). [ABSTRACT FROM AUTHOR]

This paper discusses the distribution of certainty around General Circulation Models (GCMS) - computer models used to project possible global climatic changes due to human emissions of greenhouse gases. It examines the trope of distance underpinning Donald MacKenzie's concept of 'certainty trough', and calls for a more multi-dimensional and dynamic conceptualization of how uncertainty is distributed around technology. The certainty trough describes the level of certainty attached to particular technoscientific constructions as distance increases from the site of knowledge production, and proposes that producers of a given technology and its products are the best judges of their accuracy. Processes and dynamics associated with GCM modeling challenge the simplicity of the certainty trough diagram, mainly because of difficulties with distinguishing between knowledge producers and users, and because GCMs involve multiple sites of production. This case study also challenges the assumption that knowledge producers always are the best judges of the accuracy of their models. Drawing on participant observation and interviews with climate modelers and the atmospheric scientists with whom they interact, the study discusses how modelers, and to some extent knowledge producers in general, are sometimes less able than some users to identify shortcomings of their models. [ABSTRACT FROM AUTHOR]

This paper presents the first probability-based record of flooding in Europe that spans the entire Holocene. An analysis of 506 14C dated fluvial units collected across the whole of Great Britain provides a novel and robust methodology for improving flood risk assessment by geographically and temporally extending the record of extreme flood events. Sixteen episodes of increased flooding occurrence are identified, 12 of which (at c. 11 160, 5730, 4840, 4520, 3540, 2730, 2550, 2280, 1950, 1290, 660, 570, cal. BP) are recorded in most regions, whereas four phases (at c. 6820, 5540, 1650, 860 cal. BP) affected some parts of Great Britain more than others. In all regions large variations in flood frequency and magnitude occurred before forest clearance and indicate an underlying climatic control. During the mid-Holocene there is evidence for a hydroclimatic 'system switch', which in terms of catchment hydrology in Great Britain was marked by two sudden increases in both the frequency and severity of floods at c. 5000 cal. BP and, most notably, at c. 3000 cal. BP. The marked non-stationary behaviour of the British flood series at these times reflects a regional hydrologic response to large-scale ocean–atmospheric circulation changes superimposed on a pattern reflecting both long-term land-use change and the preferential preservation of later fluvial units. Centennial-scale variations in the occurrence of extreme flood events in Great Britain appear to be a sensitive indicator of past and present climate change in the North Atlantic region. [ABSTRACT FROM AUTHOR]

On the basis of glacier and lake-level records, this paper attempts, for the first time, a comparison between high-resolution palaeohydrological and palaeoglaciological data in west-central Europe over the past 3500 years. A data set of tree-ring width, radiocarbon and archaeological data, in addition to historical sources, were used to reconstruct fluctuations of the Great Aletsch, the Gorner and the Lower Grindelwald glaciers in the Swiss Alps. The three ice-streams experienced nearly synchronous advances at c. 1000–600 BC and AD 500–600, 800–900; 1100–1200 and 1300–1860. These glacier fluctuations show strong correspondence with lake-level variations reconstructed in eastern France (Jura mountains and Pre-Alps) and on the Swiss Plateau. This supports the hypothesis of elimatically driven fluctuations. Historical date available for the period since AD 1550 reveal, in detail, various meteorological conditions behind the succesive glacier advances. Howere, in agreement with the general trend shown by the historical data, the synchroneity between glacier advances and periods of higher lake level suggests the impact of general winter cooling and an increase in summer moistur as responsible for reinforced feeding of both glaciers and lakes in west-central Europe ;over the past 3500 years. Finally, comparison between the Great Aletsech glacier and the residual 14C records supports the hypothesis that variations in solar activity were a major forcing factor of climatic oscillations in west-central Europe during the last Holocence. [ABSTRACT FROM AUTHOR]

Ice cores from the relatively low-lying ice caps in Svalbard have not been widely exploited in climatic studies owing to uncertainties about the effect of meltwater percolation. However, results from two new Svalbard ice cores, at Lomonosovfonna and Austfonna, have shown that with careful site selection, high-resolution sampling and multiple chemical analyses it is possible to recover ice cores from which part of the annual signals are preserved, despite the considerable meltwater percolation. The new Svalbard ice cores are positioned in different parts of Svalbard and cover the past 800 years. In this paper we focus on the last 400 years. The δ18O signals from the cores are qualitatively similar over most of the twentieth century, suggesting that they record the same atmospheric signal. Prior to AD 1920, the Austfonna ice core exhibits more negative δ18O values than Lomonosovfonna, although there are intermittent decadal-scale periods throughout the record with similar values. We suggest that the differences reflect the effect of the inversion layer during the winter. The pattern in the δ18O records is similar to the Longyearbyen air-temperature record, but on an annual level the correlation is low. The Austfonna record correlates well with the temperature record from the more distant and southwesterly located Jan Mayen. A comparison of the ice-core and sea-ice records from this period suggests that sea-ice extent and Austfonna δ18O are related over the past 400 years. This may reflect the position of the storm tracks and their direct influence on the relatively low-altitude Austfonna. Lomonosovfonna may be less sensitive to such changes and primarily record free atmospheric changes instead of variations in sea-ice extent, the latter is probably a result of its higher elevation. [ABSTRACT FROM AUTHOR]

Water, wind and tillage erosion are well-studied soil erosion processes. However, there is another process of soil erosion that is rarely considered in the field of earth sciences but one that should not be neglected when calculating soil denudation rates and sediment budgets, i. e., soil loss due to crop harvesting (SLCH). Loose soil and soil adhering to the crop and rock fragments are harvested and exported from the field along with crops such as sugar beet (Beta vulgaris L.), potato (Solanum tuberosum L.) and chicory (Cichorium intybus L.). In this paper several assessments of SLCH found in the literature are listed, revealing that soil loss due to crop harvesting may range from a few Mg up to a few tens of Mg per hectare per harvest. As most literature discussing this soil loss does not originate from the field of earth sciences, and terms used to describe this phenomenon are not standardized, a terminology is proposed to describe soil losses due to crop harvesting compatible with terms used in the field of soil erosion. Furthermore, the parameters determining SLCH are reviewed based on a detailed literature study that focuses mainly on sugar beet. These parameters may be grouped into four factors, i.e.soil, crop, agronomic practices and harvest technique. Variations in soil moisture and soil texture cause the largest variations in SLCH, although other factors, such as harvest technique, also play an important role. Given the importance of SLCH in terms of on-site and off-site effects, more research is needed to quantify SLCH under different environmental conditions. [ABSTRACT FROM AUTHOR]

The focus of this paper is on the reconstruction of the mid-Holocene climatic changes based on the pollen records contained in a 6.2 m thick section in the southern part of the Tengger Desert, northwestern China. To understand the modern analogues of the mid-Holocene changes, modern pollen spectra across different vegetation zones from the Qilian Mountains to the lowland Tengger Desert were studied first. Four pollen combinations were identified, corresponding to four different modern ecological environments: (1) a Picea-Artemisia combination in a spruce forest and its vicinity; (2) an Artemisia-Chenopodiaceae-Gramineae-Salix combination in a mixture belt of montane grassland and poplar woodland; (3) a Chenopodiaceae-Artemisia-Nitraria combination in a desert steppe belt; and (4) an Elaeagnus-Artemisia-Chenopodiaceae-Nitraria combination in a desert riparian forest. Our study also shows that a relatively low percentage of Picea pollen (30–10%) seems to be associated with water transportation (alluvial deposits) and a very low percentage of Picea pollen (10–5%) appears to be related to long-distance air transportation. With references to the modern relationships between pollen assemblages and associated bioclimates, the pollen sequence covering the period between 8500 and 3000 cal. BP was used to infer the climatic change history. The results show that a warmer and drier climate dominated between 8500 and 7950 cal. BP. Subsequent decreases in Artemisia and warm desert forbs/shrubs taxa and contemporaneous fluctuating increases in montane coniferous and aquatics elements from 7950 to 7400 cal. BP reflect a fluctuating increase in humidity and/or a fluctuating decrease in temperature. The following period from 7400 to 5650 cal. BP was generally warm with the Holocene Climate Optimum occurring between 7400 and 6500 cal. BP. A remarkably cool spell followed between 6500 and 6300 cal. BP that was then succeeded by a warmer and more humid period between 6300 and 5650 cal. BP. The period between 5650 and 4450 cal. BP was characterized by drastic oscillations in climatic conditions with three humid and probably cold spells intervened by three relatively dry and warm spells. The period between 4450 and 3500 cal. BP was cold and humid, followed by a wet spell as indicated by a very high percentage of Typha pollen. [ABSTRACT FROM AUTHOR]

In this paper we use a simulation approach to explore the effect of variation in taxon parameters and landscape patterning on relevant source area of pollen. We use the Prentice-Sugita model, assume constant atmospheric conditions and basin morphology, and take a reductionist approach to explore the behaviour of pollen dispersal and deposition in a simple landscape scenario. Individual factors within the scenario (pollen fall speed, relative pollen productivity, size of basic unit in the landscape mosaic, patch size, rarity of individual taxa and overall number of taxa present in the landscape) are varied while all other parameters are kept constant, thus permitting exploration of the role of different components of the system. These simulations suggest that, for basins of given size under fixed atmospheric conditions, the relevant source area of pollen is primarily an expression of the patterning of the different vegetation elements within the landscape. This has important implications for the interpretation of palaeoecological records and reconstruction of past environments. Reconstruction, especially quantitative reconstruction, requires some estimate of past relevant source area of pollen. If, as our results suggest, vegetation patterning is an important determinant of this, then it must also be taken into account when attempting to reconstruct past vegetation communities. [ABSTRACT FROM AUTHOR]

Dew has broad relevance to physical geography and many human activities. This paper reviews the observation and simulation of rural and urban dew, and the implications of dew as a climatic phenomenon. There is no universal protocol for measuring dew (i.e., condensation on cooled surfaces), its component fluxes (dewfall and distillation) or guttation, which is 'dewdrops' exuded from leaves. The many methods that exist to measure dew and surface moisture range from simple visual assessment, to electronic wetness sensors, lysimetry and remote sensing. Most studies of dew are rural; urban dew data are rare and studies seldom address dew in patchy landscapes, e.g., a forest clearing. Hardware dew models are rare. Numerous numerical models exist to simulate or forecast dew on rural crops but few address dew for surfaces other than leaves, e.g., a cocoa pod or road. There is a general consensus in the literature that dew is reduced or absent in cities because of the urban heat island effect and reduced vapour supply.However,little data exist to test this. Given the broad relevance of dew to many topics, future studies of dew in complex landscapes, including urban areas, would prove valuable. [ABSTRACT FROM AUTHOR]

Two cores of mid-Holocene raised-hog deposits from the Netherlands were [SUP14]C wiggle-match dated at high precision. Changes in local moisture conditions were inferred from the changing species composition of consecutive series of macrofossil samples Several wet-shifts were inferred, and these were often coeval with major rises in the Δ[SUP14]C archive (probably caused by major declines in solar activity). The use of Δ[SUP14]C as a proxy for changes in solar activity is validated. This paper adds to the increasing body of evidence that solar variability forced climatic changes during the Holocene. [ABSTRACT FROM AUTHOR]

Peatlands provide a widespread terrestrial archive of Holocene environmental change. The taphonomy of peat is relatively simple, the range of evidence and proxies is wide, and dating methods have become more accurate and precise, such that the potential temporal resolution of records is high. Although long established the use of peatlands as archives of Holocene change has undergone phases of decline and resurgence. Here the variable exploitation of the peat archive is explored and recent developments in peatland science as applied to Holocene records are reviewed with reference to the collection of papers in this Special Issue of The Holocene, which are arranged in four key themes: (1) records of Holocene climatic change: (2) peatland dynamics: (3) carbon accumulation: and (4) implications for conservation and management. The changing acceptance of peatlands as archives of Holocene climatic change is attributed to developments in understanding of the peatland system and geographical differences in the history of Holocene research. Recent developments in biological and geochemical proxies combined with improvements in chronological techniques have resulted in renewed interest in peatland palaeoclimate records. Peatlands are an important global carbon pool and it is clear that climate has influenced the efficiency of long-term carbon sequestration by these systems. Climate has also had an impact on the biodiversity and condition of peatlands, which creates problems in discerning cause and effect in sites affected by human activities, and in targeting remedial management. It is concluded that particular strengths of the archive are the current diversity of peat-based palaeoenvironmental research and the potential for multiproxy analyses to he applied to a range of research issues. Mire-based investigations can complement research in other realms, and are deserving of greater attention from researchers of other archives. [ABSTRACT FROM AUTHOR]

This paper examines the mid- to late-Holocene (c. 6850-1160 cal. yr BP) environmental history of Sierra de Gádor in southern Spain. The local vegetation dynamics are reconstructed through the palaeoecological record obtained from a lacustrine deposit situated at 1530 m. Various hypotheses are considered to explain the vegetation dynamics apparent in the palaeoecological evidence, including climatic change, fire occurrence and human activity. Although the vegetation in this region is sensitive to climatic change, threshold events driven by ecological factors are also apparent. Climatic events include a thermo-mesophytic optimum with abundance of deciduous trees and maximum lake water level found from c. 6850 to 5500 cal. yr BP. In contrast, changes in the frequency of major fire episodes appear to have shaped interspecific relationships and vegetation change, especially from c. 4200 cal. yr BP onwards. Biotic properties of the ecosystem such as the inertia of established tree populations, interconnected with competition adjustments, appear also to have played a role. Over the last two millennia, overgrazing, combined with natural and/or human-set fires, appears to have pushed mountain forests over a threshold leading to the spread of grassland, thorny scrub, junipers and nitrophilous communities. [ABSTRACT FROM AUTHOR]

The world's climate is changing and will continue to change into the coming century at rates projected to be unprecedented in recent human history. The risks associated with these changes are real but highly uncertain. Societal vulnerability to the risks associated with climate change may exacerbate ongoing social and economic challenges, particularly for those parts of societies dependent on resources that are sensitive to changes in climate. Risks are apparent in agriculture, fisheries and many other components that constitute the livelihood of rural populations in developing countries. In this paper we explore the nature of risk and vulnerability in the context of climate change and review the evidence on present-day adaptation in developing countries and on coordinated international action on future adaptation. We argue that all societies are fundamentally adaptive and there are many situations in the past where societies have adapted to changes in climate and to similar risks. But some sectors are more sensitive and some groups in society more vulnerable to the risks posed by climate change than others. Yet all societies need to enhance their adaptive capacity to face both present and future climate change outside their experienced coping range. The challenges of climate change for development are in the present. Observed climate change, present-day climate variability and future expectations of change are changing the course of development strategies - development agencies and governments are now planning for this adaptation challenge. The primary challenge, therefore, posed at both the scale of local natural resource management and at the scale of international agreements and actions, is to promote adaptive capacity in the context of competing sustainable development objectives. [ABSTRACT FROM AUTHOR]

Recent scientific outputs suggest that climate change is likely to cause shifts in the global pattern and intensity of flood events, in some regions increasing the exposure of populations to severe flooding. Potential future risks underline the importance of research and intervention work aimed at strengthening local capacity to cope with flooding, especially for the poor in developing countries. This paper reviews recent theoretical and applied research on vulnerability and adaptive capacity of households and communities in flood-prone areas. It traces the growing tendency for interventions to prioritize action at the local scale and suggests directions for further research to deepen understanding of actual and potential coping strategies. [ABSTRACT FROM AUTHOR]