Search

This paper studies how ordinary people in Switzerland represent and engage with environmental issues in daily practices. Bringing together conceptual developments in cultural sociology and social practice theory, the paper argues that cultural repertoires strongly shape how representations and forms of engagement play out. It identifies two main repertoires of social and environmental change: adaptation and transformation. The adaptation repertoire is reformist and aligned with individualism and the capitalist growth-paradigm; the transformation repertoire consists of a critique of the market society and calls for systemic change. Using qualitative in-depth interviews and a random survey of residents of Western Switzerland, the analyses show that most people's representations and engagements with environmental issues relate to the dominant repertoire of adaptation, which appears to be very compatible with existing social practices. Although people hint at limits to the adaptation repertoire, only very few of our study participants relate to the transformative repertoire. [ABSTRACT FROM AUTHOR]

Residential buildings have a substantial impact on global environmental impacts. In this paper we present a model that assesses impacts from materials (embodied impacts) as well as from heating (operational impacts) for all residential buildings in Switzerland. Our model builds on an existing high-resolution spatio-temporal building stock model, which estimates the space heating demand of buildings, based on building property and site data. In this work we additionally include the impacts of materials extraction, production, transportation, and disposal of building components (floors, roofs, walls, ceilings and windows). Our model comes with a site- and building-specific default parametrization for all buildings, but it is developed as a tool that allows architects and planners to adapt building and site data with specific information to increase the accuracy of the environmental assessment of the current buildings and future building-management scenarios. We applied the model to ten Swiss buildings and assessed a selection of building-management scenarios to illustrate the application of the tool. The results show that our model estimates fairly accurate values of thermal and ventilation heat transmittance, operational space heating demand, and operational and embodied climate-change impacts for the considered buildings. The detailed modeling results for the ten case study buildings outperformed the simplified version of the model with generic default values for material building composition (using age-grouped building archetypes), emphasizing the importance of adding detailed material information in building life cycle assessments. Therefore, a focus should be placed on obtaining accurate material inventories of buildings in future research. The here-developed model allows for integration of such detailed material inventories, overwriting the provided default values. • Tool provides assessment of embodied and operational impacts of the entire Swiss residential building stock. • Tool estimates close to accurate space heating demands of buildings. • Tool is equipped with generic default building and site data. • Tool allows overwriting generic values with data inputs from building stakeholders, which is demonstrated in the case study of 10 buildings. [ABSTRACT FROM AUTHOR]

Agricultural food production is both affected by and contributing to climate change. At the global scale, agri-food systems are responsible for one-third of total greenhouse gas emissions. With progressing climate change, the risks of crop failure increase. Thus, an urgent need is to reduce emissions from food systems while increasing their resilience to climate change. Enormous untapped potentials to achieve these dual goals lie in transforming agri-food systems towards more diverse, plant-based, and regional food production systems. In this paper, we present an innovative approach for identifying climate-adapted alternative food crops that could (1) help to diversify existing cropping systems and thus increase their climate resilience and can be (2) nutritious elements of plant-based regional diets with reduced emissions. The approach builds on the model ecocrop to select food crops that could benefit from regionally projected changes in climate. The model-based analysis is complemented with a literature review to examine the ecocrop results for their plausibility and provide a broader assessment of potentials for cultivation, utilization, and nutritional values of model-selected crops. The approach is applied to Switzerland, where we identify eight alternative crops with the potential to increase climate resilience while contributing to healthy human diets of regional consumers with benefits for climate mitigation (almond, pecan, sesame, durum wheat, quinoa, lentil, lupine, and borage). The literature review indicated that the increasing demand for many of these crops suggests great potential for regional marketing of crop products. The results produced in this study provide an initial guide for researchers and innovative farmers interested in experimenting with alternative crops in Switzerland, thus promoting climate-smart food system transformation from the production side. Using our unbiased bottom-up screening approach, we identified climate-adapted alternative crops that can provide essential nutrients, cover nutritional gaps in Switzerland, diversify existing production systems, and improve sustainability. [Display omitted] • Innovative bottom-up screening approach identifies climate-adapted alternative crops. • Almond, pecan, sesame, durum wheat, quinoa, lentil, lupine, and borage are identified. • Identified crops provide essential nutrients and cover nutritional gaps in Switzerland. • Selected crops can diversify existing production systems to improve sustainability. [ABSTRACT FROM AUTHOR]

This paper presents the building stock model CESAR (Combined Energy Simulation And Retrofitting), which is based on bottom-up modelling methodology for the development of sustainable energy transformation strategies for the buildings in Swiss districts. CESAR is composed of two sub-models: a Demand Model (DM) and a Retrofitting Model (RM). The DM is tasked with identifying the current energy demand of buildings in districts. It builds on geo-referenced information and available census data, and its flexibility allows it to be applicable to any kind of residential neighbourhood within Switzerland. The DM is based on an automated bottom-up modelling technique, which employs the dynamic building energy simulation software tool EnergyPlus as its simulation core to generate hourly energy demand profiles of individual buildings taking the interactions with neighbouring buildings (e.g. shading and solar inter-reflections) into account. Once current energy demands are calculated by the DM, the RM further offers the possibility to apply a set of energy transformation scenarios, based on the Swiss Energy Strategy 2050, to generate future demand and emission projections of districts including key economic indicators. Besides that, the building energy performance under climate change projections can be evaluated. In this paper, the tool is applied on three case study districts, an urban, suburban and rural area, within Switzerland and different transformation scenarios according to the Energy Strategy are investigated. Results revealed significant differences between the two implemented transformation scenarios, the Business as Usual (WWB) and the New Energy Policy (NEP). While in the WWB scenario, only a small number of buildings reaches the intended targets for primary energy and GHG emissions until 2050, the NEP scenario induces a much higher transformation of the districts. Besides that, the significance of the impact of global warming on future cooling demand is shown. [ABSTRACT FROM AUTHOR]

Phenological data have become increasingly important as indicators of long-term climate change. Consequently, long-term homogeneity of the records is an important aspect. In this paper, we apply a breakpoint detection algorithm to the phenological series from the Swiss Phenology Network (SPN). A combination of three statistical tests is applied and different constraints are tested with respect to the choice of reference series. Breakpoint detection is only possible for a fraction of the series due to the shortness of some series and the lack of suitable reference series. Spring phases are more likely to be suitable than fall phases because of their higher spatial correlation. Out of nearly 3000 phenological series with at least 20 data points, only about 5% were found to be significantly inhomogeneous, although a visual validation indicates that many mid-sized breakpoints remained undetected. The detected breakpoints were compared with metadata and more than half of them could be attributed to a change of observer. [ABSTRACT FROM AUTHOR]

The Swiss Academies have the experience of three decades of facilitating a dialogue between science and society. This includes the provision of scientific knowledge to policy decision-makers. Climate change is a topic that has been important in this context from the beginning. A recent example of science policy work in this domain has been the analysis of the findings of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), 1 and the formulation of recommendations for policy-making at a national level in order to tackle the challenges posed by climate change on the population and the environment of Switzerland. Taking this specific example, the current paper showcases how academies can provide scientific knowledge at the science–policy interface to help tackle real-world challenges. With reference to this case study, and based on their longer-term science-policy engagement, this contribution concludes by describing the elements considered as essential for a successful dialogue between the actors in science and policy-making. [ABSTRACT FROM AUTHOR]

Energy transitions towards green energy are taking place worldwide, motivated by climate change concerns. As the most used renewable technologies (i.e., wind, solar and hydro) have an unpredictable output, managing this variability is challenging. This paper uses a system dynamics approach to understand what type of regulation is required to successfully manage the simultaneous increase in demand and reduction in water resources in the Swiss electricity system, which is gradually replacing nuclear by solar generation. We address climate variability by running three climate scenarios while considering both demand side management and capacity auctions. Our findings indicate that, without government intervention, shortages occur and prices are higher. Subsidizing PV eliminates blackouts, decreases the electricity price and indirectly encourages Pumped Hydro-Storage investments. • We model a long-term transition from a nuclear-hydro to a PV-hydro generation mix. • We use IPCC scenarios to capture the impact of climate on demand and precipitations. • Relying on market-driven investments in PV and pumped-storage results in shortages. • Capacity payments for PV eliminate shortages but cause significant curtailment. • Demand-side management limits the need for curtailment resulting from PV penetration. [ABSTRACT FROM AUTHOR]

Waste wood represents as much a waste to dispose of as a secondary resource to exploit. Various studies have assessed the energy potential and/or climate impact of energy recovery from waste wood. This paper aims to assess the long-term potential of waste wood for energy production and greenhouse gas (GHG) emissions reduction in Switzerland. Material flow analysis (MFA) is applied for modelling the metabolism of wood and waste wood in the Swiss anthroposphere over one century. The energy and climate impacts are estimated for 32 scenarios which assume different forest harvesting variants and waste wood treatment options. The scenario analysis shows that waste wood treatment options are more beneficial in the long term in terms of energy production (by energy recovery from waste wood) and of GHG emission reduction than the increase in the quantities of waste wood generated in the future caused by the advocated strategies of increased forest harvesting. By using the Maximin criterion, the long-term optimal additional potential for energy recovery from waste wood is estimated at 2110 GWh/year of useful energy, which offers a reduction of 364 tonnes of CO 2 equivalents per year. As prerequisites, the nominal installed capacity of the waste wood boilers needs to be raised and their efficiency and as well as those of incineration plants need to be increased. In addition, the sustainable potential of Swiss forests must be fully exploited. This study identifies various recommendations for the optimal exploitation of energy recovery from waste wood. [ABSTRACT FROM AUTHOR]

This paper reviews the major organizations that mediate interactions between the scientific community and climate change policy-making in Switzerland. Based on seven case studies that analyze the effectiveness of policy recommendations issued by the Advisory Body on Climate Change Research and Policy, the paper demonstrates the practical insights that can be gained by applying boundary organization and advocacy coalition framework theory to the design of such institutions. Better integration of the social and management sciences could improve the ability of the Advisory Body on Climate Change Research and Policy to perform hybrid management functions essential to integrate science more effectively into decision-making processes. [ABSTRACT FROM AUTHOR]

In this paper we explore the Swedish Government's vision for the forest sector:The Forest Kingdom – with values for the world, launched in 2011. We use the issues of climate change and gender equality to demonstrate implicit “values” that underpin this recent forest policy initiative. Drawing on new institutionalism, critical discourse theory and gender as an analytical category, we conceptualise values as important governance mechanisms mediated through discourse. We analyse key documents of the Forest Kingdom, along with press releases, governmental bills and reports and direct attention to problem representations and subject positions (identity offerings) produced. Our findings demonstrate how climate change is turned into a business opportunity and a means to secure growth and employment throughout Sweden. Women are represented as potential employees and active forest owners connected to the needs of the industry, rather than as active citizens involved in forest policy-making. Climate change and gender inequality are thereby displaced from the political to an economic sphere, linked to industrial needs, private forest ownership and profit rather than to public and collective decision-making. Values underpinning these representations are economic growth, individualism and faith in markets. The emphasis on production is not dissimilar from previous forest policies, which until 1993 primarily were oriented towards timber production. [ABSTRACT FROM AUTHOR]

Shallow ground-source heat pumps (GSHPs) are a promising technology for contributing to the decarbonisation of the energy sector. In heating-dominated climates, the combined use of GSHPs for both heating and cooling increases their technical potential, defined as the maximum energy that can be exchanged with the ground, as the re-injection of excess heat from space cooling leads to a seasonal regeneration of the ground. This paper proposes a new approach to quantify the technical potential of GSHPs, accounting for effects of seasonal regeneration, and to estimate the useful energy to supply building energy demands at regional scale. The useful energy is obtained for direct heat exchange and for district heating and cooling (DHC) under several scenarios for climate change and market penetration levels of cooling systems. The case study in western Switzerland suggests that seasonal regeneration allows for annual maximum heat extraction densities above 300 kWh/m2 at heat injection densities above 330 kWh/m2. Results also show that GSHPs may cover up to 63% of cooling and 55% of heating demand for individual GSHPs in 2050 in Switzerland, which increases to 87% and 85% if DHC is used. The regional-scale results may serve to inform decision making on strategic areas for installing GSHPs. [Display omitted] • Technical potential of shallow ground-source heat pumps (GSHPs) at regional scale. • Seasonal regeneration of GSHPs by re-injection of space cooling needs to the ground. • Useful potential for supplying building energy demand under three climate scenarios. • Impact of district heating and cooling (DHC) on the useful potential of GSHPs. • Case study in western Switzerland: Up to 87% of energy potentially supplied for DHC. [ABSTRACT FROM AUTHOR]

Shallow ground-source heat pumps (GSHPs) are a promising technology for contributing to the decarbonisation of the energy sector. In heating-dominated climates, the combined use of GSHPs for both heating and cooling increases their technical potential, defined as the maximum energy that can be exchanged with the ground, as the re-injection of excess heat from space cooling leads to a seasonal regeneration of the ground. This paper proposes a new approach to quantify the technical potential of GSHPs, accounting for effects of seasonal regeneration, and to estimate the useful energy to supply building energy demands at regional scale. The useful energy is obtained for direct heat exchange and for district heating and cooling (DHC) under several scenarios for climate change and market penetration levels of cooling systems. The case study in western Switzerland suggests that seasonal regeneration allows for annual maximum heat extraction densities above 300 kWh/m2 at heat injection densities above 330 kWh/m2. Results also show that GSHPs may cover up to 63% of cooling and 55% of heating demand for individual GSHPs in 2050 in Switzerland, which increases to 87% and 85% if DHC is used. The regional-scale results may serve to inform decision making on strategic areas for installing GSHPs. [Display omitted] • Technical potential of shallow ground-source heat pumps (GSHPs) at regional scale. • Seasonal regeneration of GSHPs by re-injection of space cooling needs to the ground. • Useful potential for supplying building energy demand under three climate scenarios. • Impact of district heating and cooling (DHC) on the useful potential of GSHPs. • Case study in western Switzerland: Up to 87% of energy potentially supplied for DHC. [ABSTRACT FROM AUTHOR]

Abstract: Climate change will alter the environmental conditions for crop growth and require adjustments in management practices at the field scale. In this paper, we analyzed the impacts of two different climate change scenarios on optimal field management practices in winterwheat and grain maize production with case studies from Switzerland. Management options included nitrogen fertilization (amount, timing and allocation) as well as irrigation. Optimal solutions that maximize the farmer’s utility were sought with the help of a bioeconomic modeling system that integrated the process-based crop growth model CropSyst into an economic decision model. The latter accounted not only for the crop specific average profit margins, but also for production risks, reflecting the utility (expressed as the certainty equivalent) of a risk-averse farmer’s management decisions at field scale. In view of the non-linearity and complexity of the problem, we used a genetic algorithm as optimization technique. For grain maize, our results showed that climate change will foster the use of irrigation, not only at sites prone to water limitation already under current climatic conditions, but more in general for climate change scenarios projecting a substantial decrease in summer precipitation. For winterwheat, irrigation was never identified as an optimal management option. For both crops and sites, climate change reduced the optimum nitrogen fertilization amount and decreased for winterwheat the number of fertilization applications. In all cases, the farmer’s certainty equivalent decreased between 7% and 25% under climate change, implying negative impacts on winterwheat and grain maize production even under the assumption of an adjustment of the optimum management practices. [Copyright &y& Elsevier]

Abstract: Climate plays a fundamental role in agriculture. The quantity and quality of crop yield can be affected by water stress, heat stress or frost or by pests and diseases. As climate conditions change, suitability zones for the cultivation of specific crops may shift. For planners and land managers it is important to understand such changes in order to develop short- and long-term adaptation strategies for resource and development planning. In this paper, we present a flexible and comprehensive, rule-based approach for evaluating crop-specific climate suitability. Climate indices are calculated over dynamically estimated phenological phases, and factor suitability functions are defined to relate these phase-specific climate indices to suitability values. The dynamic consideration of crop phenology allows to assess effects of climate-induced shifts in phenological development. To complement the knowledge-based definition of factor suitability functions with empirical data, we introduce an automated procedure for refining this definition within knowledge-based bounds based on observed climate and yield data. The approach was tested and applied for grain maize (Zea mays L.) production in Switzerland. Comparison with independent yield data showed a good agreement with crop-specific climatic suitability, both in terms of temporal and spatial variability. Analysis of phase-specific suitability limitations at three representative sites revealed that suitability during the period 1981–2011 was mostly limited by sub-optimum temperatures and radiation during early and late phases, whereas drought was only an important limitation in exceptionally dry years (e.g. 2003 and 2010). An analysis of constant changes in temperature and precipitation indicated that grain maize suitability at a selected site on the western Central Plateau was more sensitive to temperature changes than to changes in precipitation. This suggests that this crop could benefit from an increase in temperature, not only through shifting towards the temperature optimum, but also by avoiding drought stress through accelerated plant development. However, these positive effects could be counteracted by negative effects of shortened phenology (i.e. reduced biomass accumulation) and heat stress. These results show that the approach offers diverse possibilities for applications, including climate impacts studies, and serves to provide information for the planning of crop adaptation strategies. [Copyright &y& Elsevier]

Summary: The European Alps are one region of the world where climate-driven changes are already perceptible, as exemplified by the general retreat of mountain glaciers over past decades. Temperatures have risen by up to 2°C since 1900 particularly at high elevations, a rate that is roughly three times the global-average 20th century warming. Regional climate models suggest that by 2100, winters in Switzerland may warm by 3–5°C and summers by 6–7°C according to greenhouse-gas emissions scenarios, while precipitation is projected to increase in winter and sharply decrease in summer. The impacts of these levels of climatic change will affect both the natural environment and a number of economic activities. Alpine glaciers may lose between 50% and 90% of their current volume and the average snowline will rise by 150m for each degree of warming. Hydrological systems will respond in quantity and seasonality to changing precipitation patterns and to the timing of snow-melt in the Alps, with a greater risk of flooding during the spring and droughts in summer and fall. The direct and indirect impacts of a warming climate will affect key economic sectors such as tourism, hydropower, agriculture and the insurance industry that will be confronted to more frequent natural disasters. This paper will thus provide an overview of the current state of knowledge on climatic change and its impacts on the Alpine world. [ABSTRACT FROM AUTHOR]

This paper reports on a method using composites for studying synoptic conditions of a series of windstorm events selected on the basis of maximum wind speeds in Switzerland. The composite storm-averaged conditions indicate how flow fields, as well as related surface conditions, are organised so as to produce high wind speeds near the surface. On average, high winds in Switzerland, mainly generated by transient synoptic-scale eddies, are characterised by a minimum in the mean sea level pressure field over southern Norway, anticyclonic conditions south of 35°N and a steep pressure gradient over continental western Europe. The geopotential aloft has a predominant zonal structure, producing high winds between 45°N and 50°N over the eastern Atlantic and further inland; the jet stream has its maximum speed at 50°N over the Celtic Sea and Brittany at 250 hPa. Close to the surface, large temperature contrasts between the warm waters of the Atlantic Ocean and Mediterranean Sea and the cooler continent are diagnosed. The results thus obtained differ to those produced by other methods based on the analysis of deep cyclones or of strong vorticity in the northern North Atlantic Ocean basin. Differences of the composite mean synoptic conditions for current (1961-1990) and future climate (2071-2100) as simulated by the Global Climate Model HadAM3H in the context of the EU PRUDENCE project indicate that windstorms in a warmer world are generated by a subtle modification of the atmospheric baroclinicity, especially over the ocean and where greater ocean-continent temperature contrasts are simulated during winters. However, there are no signs of reduced storm activity as the climate warms by the end of the twenty-first century. [ABSTRACT FROM AUTHOR]

Based on observational meteorological data since A.D. 1864 and tree-ring records of debris-flow activity, this paper assesses changes in rainfall characteristics and their impact on the triggering of geomorphic events in a high-elevation watershed of the Swiss Alps since the end of the Little Ice Age. No trends are visible in the frequency of heavy rainfall events, but we observe a reduced number of heavy, short-lived rainfalls in summer and a concentration of advective storms is recorded in late summer and early fall since the late 1980s. These changes in triggering meteorological conditions resulted in a cluster of debris flows in the early decades of the twentieth century and a lowering of debris-flow activity since the mid 1990s, and may be mirroring the observed changes in persistent high-pressure systems over the Alps. We also observe intra-seasonal differences in debris-flow system response reflecting the state of the permafrost body in the source area of debris flows, allowing for very small debris flows to be released by limited rainfall inputs (<20 mm) in June and July. The same quantities of rain will not trigger debris flows in August or September, when a thick active layer of the permafrost body is capable of absorbing water. With the projected amplitude of climatic change, seasonality, return intervals and volumes of debris flows are likely to be altered. RCM projections based on the IPCC A2 scenario suggest a decrease in heavy summer rainfalls which will most likely result in a (further) reduction of the overall frequency of debris flows, leaving more time for sediment to accumulate in the channel. Such an increase of channel accumulation rates along with the projected destabilization of the steep rock-glacier body is likely, in turn, to exert control ultimately on sediment volumes released from the source areas during future events. Observations from adjacent catchments suggest that extremely large debris flows, beyond historical experience, could occur at the study site and in similar debris-flow systems of the Valais Alps originating from periglacial environments. [ABSTRACT FROM AUTHOR]

Climate change is affecting biodiversity worldwide inducing species to either “move, adapt or die”. In this paper we propose a conceptual framework for analysing range shifts, namely a catalogue of the possible patterns of change in the distribution of a species along elevational or other environmental gradients and an improved quantitative methodology to identify and objectively describe these patterns. Patterns are defined in terms of changes occurring at the leading, trailing or both edges of the distribution: (a) leading edge expansion, (b) trailing edge retraction, (c) range expansion, (d) optimum shift, (e) expansion, (f) retraction, and (g) shift. The methodology is based on the modelling of species distributions along a gradient using generalized additive models (GAMs). Separate models are calibrated for two distinct periods of assessment and response curves are compared over five reference points. Changes occurred at these points are formalized into a code that ultimately designates the corresponding change pattern. We tested the proposed methodology using data from the Swiss national common breeding bird survey. The elevational distributions of 95 bird species were modelled for the periods 1999–2002 and 2004–2007 and significant upward shifts (all patterns confounded) were identified for 35% of the species. Over the same period, an increase in mean temperature was registered for Switzerland. In consideration of the short period covered by the case study, assessed change patterns are considered to correspond to intermediate patterns in an ongoing shifting process. However, similar patterns can be determined by habitat barriers, land use/land cover changes, competition with concurrent or invasive species or different warming rates at different elevations. [Copyright &y& Elsevier]

Abstract: A widespread risk in high mountains is related to the accumulation of loose sediments on steep slopes, which represent potential sources of different types of geomorphic processes including debris flows. This paper combines data on 50yr of permafrost creep at the Ritigraben rock glacier (Valais, Swiss Alps) with magnitude–frequency (M–F) relationships of debris flows recorded in the Ritigraben torrent originating at the rock-glacier front. Debris production and volumetric changes at the rock-glacier front are compared with debris-flow activity recorded on the cone and potential couplings and feedbacks between debris sources, channel processes and debris sinks. The dataset existing for the Ritigraben rock glacier and its debris-flow system is unique and allows prime insights into controls and dynamics of permafrost processes and related debris-flow activity in a constantly changing and warming high-altitude environment. Acceleration in rock-glacier movement rates is observed in the (1950s and) 1960s, followed by a decrease in flow rates by the 1970s, before movements increase again after the early 1990s. At a decadal scale, measured changes in rock-glacier movements at Ritigraben are in concert with changes in atmospheric temperatures in the Alps. Geodetic data indicates displacement rates in the frontal part of the rock glacier of up to 0.6–0.9myr− 1 since the beginning of systematic measurements in 1995. While the Ritigraben rock glacier has always formed a sediment reservoir for the associated debris-flow system, annual horizontal displacement rates of the rock-glacier body have remained quite small and are in the order of decimeters under current climatic conditions. Sediment delivery from the rock-glacier front alone could not therefore be sufficient to support the 16 debris flows reconstructed on the cone since 1958. On the contrary, debris accumulated at the foot of the rock glacier, landslide and rockfall activity as well as the partial collapse of oversteepened channel walls have to be seen as important sediment sources of debris flows at Ritigraben and would represent 65–90% of the material arriving on the Ritigraben cone. There does not seem to exist a direct coupling between displacement rates of and sediment delivery by the rock-glacier body and the frequency of small- and medium-magnitude debris flows. In contrast, a direct link between source and sink processes clearly exists in the case of active-layer failures. In this case, failure processes at the rock-glacier snout and debris-flow events in the channel occur simultaneously and are both triggered by the rainfall event. [Copyright &y& Elsevier]

Abstract: Debris-flow activity in a watershed is usually defined in terms of magnitude and frequency. While magnitude–frequency (M–F) relations have long formed the basis for risk assessment and engineering design in hydrology and fluvial hydraulics, only fragmentary and insufficiently specified data for debris flows exists. This paper reconstructs M–F relationships of 62 debris flows for an aggradational cone of a small (<5km2), high elevation watershed in the Swiss Alps since A.D. 1863. The frequency of debris flows is obtained from tree-ring records. The magnitude of individual events is given as S, M, L, XL, and derived from volumetric data of deposits, grain size distributions of boulders, and a series of surrogates (snout elevations, tree survival, lateral spread of surges). Class S and M debris flows (<5×103 m3) encompass a typical size of events and have mean recurrence intervals of 5.4 (SD: 3.2) and 7.4years (SD: 6.7), respectively. Class XL events (104–5×104 m3) are, in contrast, only identified three times over the past 150years, and major erosional activity on the cone was restricted to two of these events in 1948 and 1993. A comparison of results with hydrometeorological records shows that class L and XL events are typically triggered by advective storms (rainfall >50mm) in August and September, when the active layer of the rock glacier in the source area of debris flows is largest. Over the past ∼150years, climate has exerted control on material released from the source area and prevented triggering of class XL events before 1922. With the projected climatic change, permafrost degradation and the potential increase in storm intensity are likely to produce “class XXL” events in the future with volumes surpassing 5×104 m3 at the level of the debris-flow cone. [Copyright &y& Elsevier]

A coupling interface between the regional climate model REMO and a distributed glacier mass balance model is presented in a series of two papers. The first part describes and evaluates the reanalysis-driven regional climate simulation that is used to force a mass balance model for two glaciers of the Swiss mass balance network. The detailed validation of near-surface air temperature, precipitation, and global radiation for the European Alps shows that the basic spatial and temporal patterns of all three parameters are reproduced by REMO. Compared to the Climatic Research Unit (CRU) dataset, the Alpine mean temperature is underestimated by 0.34°C. Annual precipitation shows a positive bias of 17% (30%) with respect to the uncorrected gridded ALP-IMP (CRU) dataset. A number of important and systematic model biases arise in high-elevation regions, namely, a negative temperature bias in winter, a bias of seasonal precipitation (positive or negative, depending on gridbox altitude and season), and an underestimation of springtime and overestimation of summertime global radiation. These can be expected to have a strong effect on the simulated glacier mass balance. It is recommended to account for these shortcomings by applying correction procedures before using the RCM output for subsequent mass balance modeling. Despite the obvious model deficiencies in high-elevation regions, the new interface broadens the scope of application of glacier mass balance models and will allow for a straightforward assessment of future climate change impacts. [ABSTRACT FROM AUTHOR]

Abstract: The 2007 edition of the Global Change Research Workshops brought over 50 researchers from all over the world to Wengen, Switzerland to review the state of the art with respect to desertification, particularly in the light of climate change. They set out to identify critical knowledge gaps and make recommendations for further research from a wide range of perspectives in both the natural and social sciences. Recent achievements both within discipline and new inter-disciplinary areas were highlighted. Effective communication between the researchers and high-level users of synthetic environmental information, such as international agencies, development programmes and concerned organizations operating in the field was emphasised. This introductory paper provides background to the workshop and highlights the key findings and outcomes of the conference. The findings that emerged from those discussions are summarized, and some further thoughts about recommended next steps are provided. [Copyright &y& Elsevier]

Abstract: The implementation of new high-speed transport technologies re-shapes the demand balance between transport modes and rebound effects may occur. In this paper first a definition of environmental rebound effects of high-speed transport is presented and various cases are discussed. Second, a method is developed to determine and quantify the environmental rebound effects employing life cycle assessment. The method is illustrated in a case study by investigating the greenhouse gas emissions of a frequently discussed future underground maglev train system for Switzerland. The environmental rebound effect expresses the size of environmental impact changes due to demand corrections in relation to the plain substitution effect. The latter expresses efficiency substitution effects due to the substitution of existing transport services with a high-speed transport service; i.e. passenger-kilometre performance remains constant in a world with and without the new transport service. Demand corrections are determined employing the notion of the constant travel time budget, assuming that if travel speed increases, the time saved will be exclusively used to travel more and further. In order to quantify the environmental rebound effect we determined the environmental efficiency – including operation, energy supply, vehicle supply and infrastructure supply – for all important transport services of the current passenger transport system as well as for the new transport technology. In addition, we generated and quantified a set of cornerstone scenarios to address possible changes in mobility patterns and technological options of passenger car transport at the time when the new high-speed transport technology would be in operation. The results show an increase of per capita environmental impact for all considered scenarios even without accounting for additional transport demand due to time saving effects. All scenarios show additional environmental impacts due to rebound effects on top of pure substitution effects. The case study demonstrates that taking into account demand changes, i.e. rebound effects is essential to evaluate emerging transport technologies. New technologies allowing for higher travel speed, even if energy-efficient on a passenger-kilometre basis, might lead to higher environmental impacts. This is ignored by the traditional approach of environmental transport assessment, which compares environmental efficiency of each transport mode separately. The presented approach allows to better understand the consequences of new transport services, and facilitates the assessment of future transport technologies on the level of the transport system as a whole. [Copyright &y& Elsevier]

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]

Aim Many species are currently expanding their ranges in response to climate change, but the mechanisms underlying these range expansions are in many cases poorly understood. In this paper we explore potential climatic factors governing the recent establishment of new palm populations far to the north of any other viable palm population in the world. Location Southern Switzerland, Europe, Asia and the world. Methods We identified ecological threshold values for the target species, Trachycarpus fortunei, based on gridded climate data, altitude and distributional records from the native range and applied them to the introduced range using local field monitoring and measured meteorological data as well as a bioclimatic model. Results We identified a strong relationship between minimum winter temperatures, influenced by growing season length and the distribution of the palm in its native range. Recent climate change strongly coincides with the palm's recent spread into southern Switzerland, which is in concert with the expansion of the global range of palms across various continents. Main conclusions Our results strongly suggest that the expansion of palms into (semi-)natural forests is driven by changes in winter temperature and growing season length and not by delayed population expansion. This implies that this rapid expansion is likely to continue in the future under a warming climate. Palms in general, and T. fortunei in particular, are significant bioindicators across continents for present-day climate change and reflect a global signal towards warmer conditions. [ABSTRACT FROM AUTHOR]

There is growing evidence that, as a result of global climate change, some of the most severe weather events could become more frequent in Europe over the next 50 to 100 years. The paper aims to (i) describe observed trends and scenarios for summer heat waves, windstorms and heavy precipitation, based on results from simulations with global circulation models, regional climate models, and other downscaling procedures, and (ii) discuss potential impacts on agricultural systems and forests in Switzerland. Trends and scenarios project more frequent heavy precipitation during winter corresponding, for example, to a three-fold increase in the exceedance of today's 15-year extreme values by the end of the 21st century. This increases the risk of large-scale flooding and loss of topsoil due to erosion. In contrast, constraints in agricultural practice due to waterlogged soils may become less in a warmer climate. In summer, the most remarkable trend is a decrease in the frequency of wet days, and shorter return times of heat waves and droughts. This increases the risk of losses of crop yield and forage quality. In forests, the more frequent occurrence of dry years may accelerate the replacement of sensitive tree species and reduce carbon stocks, and the projected slight increase in the frequency of extreme storms by the end of the century could increase the risk of windthrow. Some possible measures to maintain goods and services of agricultural and forest ecosystems are mentioned, but it is suggested that more frequent extremes may have more severe consequences than progressive changes in means. In order to effectively decrease the risk for social and economic impacts, long-term adaptive strategies in agriculture and silviculture, investments for prevention, and new insurance concepts seem necessary. [ABSTRACT FROM AUTHOR]

Long-living wood products contribute to the mitigation of climate change in many ways. They act as a carbon pool during their service life, as they withdraw CO2 from its natural cycle. After their service life, they can substitute for fossil fuels if they are incinerated in adequate furnaces. Furthermore, wood products can substitute for more energy-intense products made of 'conventional' materials. This paper quantifies the substitution and pool effects of an increased use of wood in the building sector in Switzerland for the years 2000-2130. Life cycle data on greenhouse gas (GHG) emissions of 12 wood products and their substitutes are used as proxies for relevant building products; this data is linked to the forecasted wood flows for each group of building products in a cohort-model. For the political assessment, GHG effects occurring abroad and in Switzerland are distinguished. The results show that the pool effect of an increased use of long-living wood products is of minor importance, whereas the energetic and material substitution effects are much more relevant, especially on a long-term. For construction products, the Swiss share of the GHG effect related to the material substitution is relatively high, as mainly nationally produced materials are substituted for. For interior products, the Swiss share of the GHG effect related to the material substitution is rather small because mainly imports are substituted for. The results must be considered as rough estimates. Nonetheless, these calculations show that an increased use of wood in the building sector is a valid and valuable option for the mitigation of greenhouse gas emissions and for reaching GHG emission targets in a mid- to long-term. Still, the pool and substitution capacity of an increased use of wood is relatively small compared to the overall GHG emissions of Switzerland. [ABSTRACT FROM AUTHOR]

Determination of the scale of the interaction between precipitation and topography is important for the accurate interpolation of rainfall in mountainous areas and also provides insight into the physical processes involved. In this paper, trivariate thin-plate smoothing splines are used to investigate the scale of interaction between monthly precipitation and topography by interpolating monthly rainfall over three subregions of the Australian continent, incorporating different climatic conditions and rainfall types. The interpolations are based upon elevations derived from digital elevation models (DEMs) of various resolutions. All of the DEMs are local averages of version 2.0 of the 9-s-resolution DEM of Australia. The results suggest that the optimal scale of the interaction between precipitation and topography, as it pertains to the elevation-dependent interpolation of monthly precipitation in Australia, is between 5 and 10 km. This is in agreement with results of similar studies that addressed daily precipitation over Switzerland. [ABSTRACT FROM AUTHOR]

This special issue of Climatic Change contains a series of research and review articles, arising from papers that were presented and discussed at a workshop held in Davos, Switzerland on 25–28 June 2001. The workshop was titled `Climate Change at High Elevation Sites: Emerging Impacts', and was convened to reprise an earlier conference on the same subject that was held in Wengen, Switzerland in 1995 (Diaz et al., 1997). The Davos meeting had as its main goals, a discussion of the following key issues: (1) reviewing recent climatic trends in high elevation regions of the world, (2) assessing the reliability of various biological indicators as indicators of climatic change, and (3) assessing whether physical impacts of climatic change in high elevation areas are becoming evident, and to discuss a range of monitoring strategies needed to observe and to understand the nature of any changes. [ABSTRACT FROM AUTHOR]

Since extreme values of climatic actions are commonly derived assuming the climate being stationary over time, engineering structures and infrastructures are designed considering design actions derived under this assumption. Owing to the increased relevance of the expected climate change effects and the correlated variations of climate actions extremes, ad hoc strategies for future adaption of design loads are needed. Moreover, as current European maps for climatic actions are generally based on observations collected more than 20 years ago, they should be updated. By a suitable elaboration of the projections of future climate changes, the evolution over time of climatic actions can be assessed; this basic and crucial information allows us to facilitate future adaptations of climatic load maps, thus improving the climate resilience of structures and infrastructures. In this paper, current trends of climatic actions in Europe, daily maximum and minimum temperatures, daily precipitation, and ground snow loads, are investigated based on available gridded datasets of observations (E-OBS) and regional reanalysis (Uncertainties in Ensembles of Regional Re-Analyses, UERRA), to assess their suitability to be used in the elaboration of maps for climatic actions. The results indicate that the E-OBS gridded datasets reproduce trends in extreme temperatures and precipitation well in the investigated regions, while reanalysis data, which include snow water equivalent, show biases in the assessment of ground snow load modifications over the years in comparison with measurements. As far as climate change effects are concerned, trends of variation of climatic actions are estimated considering subsequent time windows, 40 years in duration, covering the period 1950–2020. Results, in terms of factors of change, are critically discussed, also in comparison with the elaborations of reliable datasets of real observations, considering a case study covering Germany and Switzerland. [ABSTRACT FROM AUTHOR]

Conceptual schema illustrating the buffering role of groundwater during future summer low-flow periods in an alpine catchment. It shows the evolution of monthly mean recharge, snow water equivalent and discharge in the reference and the future period 2085 for a scenario RCP 8.5 with a strong increase in temperatures and decrease in summer precipitations. • Quaternary deposits play a critical role in seasonally storing alpine groundwater. • In future summer, the decrease in alpine discharge depends on groundwater storage. • The actual winter low flow appears as a lower bound for the future summer low flow. Alpine environments are particularly vulnerable to climatic warming, and long term observations suggest a shift of snow-influenced river discharge towards earlier periods of the year. For water resources management, the seasonal patterns of discharge in alpine areas are particularly relevant, as the shift to lower flows in summer and autumn combined with increased water demand could lead to water shortage in downstream catchments. The storage of groundwater in alpine catchments could significantly modulate how changing climatic conditions influence the annual streamflow regime. However, groundwater storage and its buffering capacity in alpine areas remain poorly understood. Moreover, studies on how climate change will impact water resources in alpine areas rarely consider the influence of geology. In this paper, catchment geology is used as a basis for the classification of future summer low flows behavior of several alpine catchments in Switzerland. Based on the analysis of the relationship between low-flow indicators and geology, the role of unconsolidated quaternary deposits is explored. We show that quaternary deposits play a critical role in the seasonal storage of groundwater, which can contribute to rivers during low-flow periods. Three climate change simulations based on extreme RCP 8.5 scenarios are fed into a conceptual hydrological model to illustrate the buffering role of groundwater. Past and future low flows normalized by mean past and future streamflows appear correlated with the percentage of unconsolidated quaternary deposits. These results highlight that catchments with high groundwater contribution to streamflow relative to precipitation will have a slower decrease in future summer discharge. Therefore, we propose two indicators that can be used to anticipate the response of future summers low flows in alpine areas to climate change: the current winter low flows and the percentage of unconsolidated quaternary deposits of the catchments. [ABSTRACT FROM AUTHOR]

Climate change motivates the pursuit of more efficient solutions for heating and cooling of buildings in order to reduce greenhouse gas emissions. While many investigations have been made into how efficiencies can be improved on a technology level, far less are present for how climate change affects the future heating and cooling demand. In this paper, we analyze the extent in which global climate trends change the theoretical heating and cooling demand of buildings. The results are based on the link between heating and cooling of buildings versus climate, and the definition of steps leading from climate to energy consumption. Three different climate scenarios are considered by using the EURO-CORDEX simulations for the case study of Swiss heating and cooling demand. The most severe climate scenario RCP8.5 leads to a −40% decrease of heating degree days and a + 1300% increase of cooling degree days by the end of the century. The presented results can be used for energy system models and for future building design criteria. [ABSTRACT FROM AUTHOR]