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Abstract: The pulp and paper industry both uses and produces large amounts of energy and rising fuel prices bring along significant challenges to the sector. Several strategies can be applied in order to remain competitive e.g. an increase in energy efficiency, a switch in fuel and/or a novel energy conversion technology. In this study, we investigate if improved energy conversion strategies can reduce energy costs, primary energy use and CO2 emissions of paper mills within different European countries (The Netherlands, Poland and Sweden). Our results show that differences in history and availability of resources has led to different conversion strategies in the three countries. We found that a natural gas combined cycle, which is largely implemented in The Netherlands due to long term domestic availability of natural gas, has the lowest primary energy demand. Due to a long history of low electricity prices, CHP has not been common in Sweden. Many Swedish mills use biomass as an energy source and due to low CO2 emissions of the national grid the CO2 emission profile of the Swedish paper industry is very low. Our results imply that future conversion routes for the Swedish paper and board industry are again wood based; in case of increasing electricity prices these would be biomass gasification based CHP solutions. With a reduction of 800kg CO2/ton paper on average, a switch from coal to biomass would reduce CO2 emissions in the Polish pulp and paper industry with approximately 0.6Mton/year. A carbon price of 20–25€/ton would, according to our results, be enough to provoke this switch. Due to the high share of natural gas, the CO2 emission reduction potential of the Dutch paper industry (1.5Mton/year) is even larger than in Poland. Due to high biomass prices and relative low CO2 emission profile of natural gas, a carbon prices of more than 60€/ton CO2 would be needed to provoke a switch in The Netherlands. Provided with few alternatives, the most effective strategy in The Netherlands would be an increase in energy efficiency. [Copyright &y& Elsevier]

Fluxes of carbon dioxide (CO2) and methane (CH4) from lakes may have a large impact on the magnitude of the terrestrial carbon sink. Traditionally lake fluxes have been measured using the floating chambers (FC) technique, however, several recent studies use the eddy covariance (EC) method. We present simultaneous flux measurements using both methods at the lake Tämnaren in Sweden during field campaigns in 2011 and 2012. Only very few similar studies exist. For CO2 flux, the two methods agree relatively well during some periods, but deviate substantially at other times. The large discrepancies might be caused by heterogeneity of partial pressure of CO2 (pCO2 w ) in the EC flux footprint. The methods agree better for CH4 fluxes, it is, however, clear that short-term discontinuous FC measurements are likely to miss important high flux events. [ABSTRACT FROM AUTHOR]

The area of dedicated energy crops is expected to increase in Sweden. This will result in direct land use changes, which may affect the carbon stocks in soil and biomass, as well as yield levels and the use of inputs. Carbon dioxide ( CO2) fluxes of biomass are often not considered when calculating the climate impact in life cycle assessments ( LCA) assuming that the CO2 released at combustion has recently been captured by the biomass in question. With the extended time lag between capture and release of CO2 inherent in many perennial bioenergy systems, the relation between carbon neutrality and climate neutrality may be questioned. In this paper, previously published methodologies and models are combined in a methodological framework that can assist LCA practitioners in interpreting the time-dependent climate impact of a bioenergy system. The treatment of carbon differs from conventional LCA practice in that no distinction is made between fossil and biogenic carbon. A time-dependent indicator is used to enable a representation of the climate impact that is not dependent on the choice of a specific characterization time horizon or time of evaluation and that does not use characterization factors, such as global warming potential and global temperature potential. The indicator used to aid in the interpretation phase of this paper is global mean surface temperature change (Δ Ts( n)). A theoretical system producing willow for district heating was used to study land use change effects depending on previous land use and variations in the standing biomass carbon stocks. When replacing annual crops with willow this system presented a cooling contribution to Δ Ts( n). However, the first years after establishing the willow plantation it presented a warming contribution to Δ Ts( n). This behavior was due mainly to soil organic carbon ( SOC) variation. A rapid initial increase in standing biomass counteracted the initial SOC loss. [ABSTRACT FROM AUTHOR]

There is concern that the carbon prices generated through climate policies are too low to create the incentives necessary to stimulate technological development. This paper empirically analyzes how the Swedish carbon dioxide (CO 2 ) tax and the European Union emission trading system (EU ETS) have affected productivity development in the Swedish pulp and paper industry 1998−2008. A Luenberger total factor productivity (TFP) indicator is computed using data envelopment analysis. The results show that climate policy had a modest impact on technological development in the pulp and paper industry, and if significant it was negative. The price of fossil fuels, on the contrary, seems to have created important incentives for technological development. Hence, the results suggest that the carbon prices faced by the industry through EU ETS and the CO 2 tax have been too low. Even though the data for this study is specific for Sweden, the models and results are applicable internationally. When designing policy to mitigate CO 2 emissions, it is vital that the policy creates a carbon price that is high enough – otherwise the pressure on technological development will not be sufficiently strong. [ABSTRACT FROM AUTHOR]

Established practice is available as a reference for evaluating sustainable transport and CO2 emissions at national, European and global levels, but comparing corresponding systems at the regional and local levels are more challenging. Therefore, this paper analyses the use of indicators, evaluation methods and data availability at local and regional levels for applied policies and measures in transport planning. Sweden is used as a case study. Available data show that total surveys (e.g., vehicle registry data), sample surveys (e.g., interviews) or modelling can be used to develop transport indicators, and that either generated (volume generated in the area) or performed (volume in the area) traffic and transportation is estimated. However, there are limitations with all methods and the design of evaluations needs careful consideration in order to reflect changes in local and regional transport systems and to relate those changes to specific measures and policies. In most cases, survey methods need to be used in order to follow up the most common indicators. All evaluation methods need to be complemented with analyses of a baseline to determine additionality and also potential rebound effects need to be considered, which requires the application of a wider systems perspective. [ABSTRACT FROM AUTHOR]

District heating satisfies about 60% of the heat demand in Swedish buildings. Today, more than two thirds of the heat supply to the district heating systems is based on biomass and waste, and biomass alone accounts for about half of the heat supply. The purpose of this paper is to present the Swedish experiences of introducing and expanding the use of biomass in the district heating systems and to identify the main drivers behind this development. Our five research questions and the corresponding conclusions consider the driving forces from energy policy tools and local initiatives, the biomass prices, the established infrastructures in forestry and district heating, the technology paths for biomass conversion, and finally the future challenge of competing uses of biomass. [ABSTRACT FROM AUTHOR]

One of the most important aspects of working in an office environment is ensuring that the space has optimal thermal comfort and an indoor environment. The aim of this research is to investigate the thermal comfort and indoor climate in three office rooms located at one of the campus buildings at the University of Gävle, Sweden. The evaluated period is in the month of April during springtime. During this period, parameters such as temperature, relative humidity, CO2, supply air flow rate, and room air velocities are measured on site. The results of the measurement show that the indoor temperature is on average lower in the rooms facing north, at 21–23.5 °C, compared to the rooms facing south, which reach high temperatures during sunny days, up to 26 °C. The results also show that the ventilation air supply rate is lower than the requirement for offices in two of the office rooms. The ACH rate is also low, at ≈ 1 h−1 for all the rooms, compared to the required levels of 2–4 h−1. The CO2 levels are within the recommended values; on average, the highest is in one of the south-facing rooms, with 768 ppm, and the maximum measured value is also in the same room, with 1273 ppm for a short period of time. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) provide a cost-effective way to fill in gaps between surface in situ observations and remotely sensed data from space. In this study, a novel portable CO2 measuring system suitable for operations on board small-sized UAVs has been developed and validated. It is based on a low-cost commercial nondispersive near-infrared (NDIR) CO2 sensor (Senseair AB, Sweden), with a total weight of 1058 g, including batteries. The system performs in situ measurements autonomously, allowing for its integration into various platforms. Accuracy and linearity tests in the lab showed that the precision remains within ± 1 ppm (1 σ) at 1 Hz. Corrections due to temperature and pressure changes were applied following environmental chamber experiments. The accuracy of the system in the field was validated against a reference instrument (Picarro, USA) on board a piloted aircraft and it was found to be ± 2 ppm (1 σ) at 1 Hz and ± 1 ppm (1 σ) at 1 min. Due to its fast response, the system has the capacity to measure CO2 mole fraction changes at 1 Hz, thus allowing the monitoring of CO2 emission plumes and of the characteristics of their spatial and temporal distribution. Details of the measurement system and field implementations are described to support future UAV platform applications for atmospheric trace gas measurements. [ABSTRACT FROM AUTHOR]

Biogas solutions offer many advantages to improve sustainable development, but there is still untapped potential in its environmental performance. During biogas upgrading, CO 2 is separated from the gas to deliver a flow with high methane concentration and thus high energy content. In this practice, CO 2 is commonly emitted to the atmosphere without contributing to a net addition of climate gases because of its biological origin, being a missed opportunity for carbon capture. In this paper, CO 2 valorization is an option that has been evaluated using a qualitative and quantitative approach, taking Sweden as an example. Results showed that around 140 kt of CO 2 can potentially be captured and utilized from biogas upgrading, which can significantly increase in future scenarios. If CO 2 were turned into methane using power-to-gas technology, an additional 35% of biogas could be produced in the short term, meaning up to additional 0.7 TWh in 2020. By 2050, around 600 to 1600 kt of CO 2 could be available, depending on how well the biogas production develops and how much of the biogas is upgraded, resulting in up to 6.2 TWh of biomethane. The qualitative assessment suggested that only minor modifications in the upgrading process are required for this practice. Biogas actors are interested in getting involved in valorization projects that enhance their circular business and avoid carbon lock-in mainly to improve the environmental performance of biomethane. Moreover, the application of CO 2 valorization requires collaboration with different actors to integrate current CO 2 demand or innovative transformation technologies. [Display omitted] • 140 kt of CO 2 could be obtained from biogas plants with an important rise in the future. • Future biomethane production could deliver from 600 to 1600 kt of CO 2 for valorization. • Higher CO 2 potential from biogas in the southern and central parts of Sweden. • In the short term, CO 2 methanation from biogas could provide 35% additional biogas. • Actors perceive CCU as an opportunity to enhance the circularity of biogas solutions. [ABSTRACT FROM AUTHOR]

Ecotechnologies have the potential to reduce the use of finite resources while providing a variety of co-benefits to society, though they often lack in market competitiveness. In this study, we investigate the sustainability of ecotechnologies for recovering carbon and nutrients, and demonstrate how a so-called "bottom-up" approach can serve as a decision-making instrument. Based on three case study catchments with a focus on domestic wastewater in Sweden and Poland, and on manure, grass and blackwater substrates in Finland, we apply a cost–benefit analysis (CBA) on system alternatives derived from a participatory process. After drawing on an initial systematic mapping of relevant ecotechnologies, the scope of the CBA is determined by stakeholder suggestions, namely in terms of the considered assessment criteria, the physical impacts and the utilised data. Thus, this CBA is rooted in a localised consideration of ecotechnologies rather than a centralised governmental approach to systems boundaries. The key advantage of applying such a bottom-up approach is that it has gone through a robust participatory selection process by local stakeholders, which provides more legitimacy to the decisions reached compared with traditional feasibility studies. Despite considering the revenues of the recovered products as well as the provision of the non-market goods CO2 mitigation and reduced eutrophication, findings from this study indicate that the benefits of the considered ecotechnologies are often outweighed by their costs. Only anaerobic digestion of agricultural wastes appears to be economically feasible under the current conditions, highlighting that further efforts and incentives may be required to mainstream ecotechnologies. [ABSTRACT FROM AUTHOR]

Abstract: Ethanol can be produced with little impact on the environment through the use of polygeneration technology. This paper evaluates the potential of integrating a lignocellulosic ethanol plant into a district heating system by case study; the plant has an ethanol capacity of 95MW with biogas, electricity and heat as by-products. Stockholm’s district heating system is used as the case study, but the results may be relevant also for other urban areas. The system has been studied using MODEST – an optimisation model framework. The results show that introducing the plant would lead to a significant reduction in the cost of heat production. The income from the biofuels and electricity produced would be about €76million and €130million annually, respectively, which is an increase of 70% compared to the income from the electricity produced in the system today. Assuming that the electricity produced will replace marginal electricity on the European electricity market and that the biofuel produced will replace gasoline in the transport sector, the introduction of the polygeneration plant in the district heating system would lead to a reduction of global CO2 emissions of about 0.7million tonnes annually. [Copyright &y& Elsevier]

Aquatic ecosystems are major sources of greenhouse gases (GHGs). Robust measurements of natural GHG emissions are vital for evaluating regional to global carbon budgets and for assessing climate feedbacks of natural emissions to improve climate models. Diffusive and ebullitive (bubble) transport are two major pathways of gas release from surface waters. To capture the high temporal variability of these fluxes in a well-defined footprint, we designed and built an inexpensive device that includes an easily mobile diffusive flux chamber and a bubble counter all in one. In addition to automatically collecting gas samples for subsequent various analyses in the laboratory, this device also utilized a low-cost carbon dioxide (CO2) sensor (SenseAir, Sweden) and methane (CH4) sensor (Figaro, Japan) to measure GHG fluxes. Each of the devices was equipped with an XBee module to enable local radio communication (DigiMesh network) for time synchronization and data readout at a server controller station on the lakeshore. The software of this server controller was operated on a low-cost computer (Raspberry Pi), which has a 3G connection for remote control and monitor functions from anywhere in the world. This study shows the potential of a low-cost automatic sensor network system for studying GHG fluxes on lakes in remote locations. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to examine climate impact from diet across background and sociodemographic characteristics in a population-based cohort in northern Sweden.Design: A cross-sectional study within the Västerbotten Intervention Programme. Dietary data from a 64-item food frequency questionnaire collected during 1996-2016 were used. Energy-adjusted greenhouse gas emissions (GHGE) for all participants, expressed as kg carbon dioxide equivalents/day and 4184 kJ (1000 kcal), were estimated using data from life cycle analyses. Differences in background and sociodemographic characteristics were examined between participants with low and high GHGE from diet, respectively. The variables evaluated were age, BMI, physical activity, marital status, level of education, smoking, and residence.Setting: Västerbotten county in northern Sweden.Participants: In total, 46 893 women and 45 766 men aged 29-65 years.Results: Differences in GHGE from diet were found across the majority of examined variables. The strongest associations were found between GHGE from diet and age, BMI, education, and residence (all P < 0·001), with the highest GHGE from diet found among women and men who were younger, had a higher BMI, higher educational level, and lived in urban areas.Conclusions: This study is one of the first to examine climate impact from diet across background and sociodemographic characteristics. The results show that climate impact from diet is associated with age, BMI, residence and educational level amongst men and women in Västerbotten, Sweden. These results define potential target populations where public health interventions addressing a move towards more climate-friendly food choices and reduced climate impact from diet could be most effective. [ABSTRACT FROM AUTHOR]

The effects of the past century's increase in atmospheric CO2 concentration ([CO2]) have been recorded in the stable carbon isotope composition (δ13C) of the annual growth rings of trees. The isotope record frequently shows increases in photosynthetic CO2 uptake relative to stomatal conductance, which estimates the CO2 concentration gradient across the stomata (ca − ci). This variable, which is one control over the net photosynthetic rate, has been suggested as a homeostatic gas-exchange set point that is easy to estimate from δ13C and [CO2]. However, in high-latitude conifer forests, the literature is mixed; some studies show increases in (ca − ci) and others show homeostasis. Here we present leaf and tree-ring δ13C data from a controlled experiment that tested factorial combinations of elevated [CO2] (365 and 700 ∝mol mol−1) and fertilization on mature Norway spruce (Picea abies (L.) Karst.) trees in northern Sweden. We found first that the leaf carbon pool was contaminated by the current photosynthate in the older leaf cohorts. This is the reverse of the common observation that older photosynthate reserves can be used to produce new tissue; here the older tissue contains recent photosynthate. We found that the tree-ring data lack such contamination and in any case they better integrate over the canopy and the growing season than do leaves. In the second and third years of treatment, elevated [CO2] alone increased (ca − ci) by 38%; when combined with fertilization, it increased (ca − ci) by 60%. The results of this study support the idea that annual rings provide a clearer isotopic signal than do foliage age-classes. The tree-ring data show that inferred (ca − ci) depends not only on [CO2], but also on mineral-nutrient status. The differences in (ca − ci) are sufficiently large to account for the treatment-induced increase in wood-volume production in these stands. [ABSTRACT FROM AUTHOR]

ABSTRACT Size resolved aerosol and gas fluxes were measured in Stockholm from 1 April 2008 to 15 April 2009 over both urban and green sectors. CO2 and H2O fluxes peaked in daytime for all seasons. CO2 concentrations peaked in winter. Due to vegetation influence the CO2 fluxes had different diurnal cycles and magnitude in the two sectors. In the urban sector, CO2 fluxes indicated a net source. The sector dominated by residential areas and green spaces had its highest aerosol fluxes in winter. In spring, super micrometer concentrations for both sectors were significantly higher, as were the urban sector rush hour fluxes. The submicrometer aerosol fluxes had a similar diurnal pattern with daytime maxima for all seasons. This suggests that only the super micrometer aerosol emissions are dependent on season. During spring there was a clear difference in super micrometer fluxes between wet and dry streets. Our direct flux measurements have improved the understanding of the processes behind these aerosol emissions. They support the hypothesis that the spring peak in aerosol emissions are due to road dust, produced during the winter, but not released in large quantities until the roads dry up during spring, and explain why Stockholm has problems meeting the EU directive for aerosol mass (PM10). [ABSTRACT FROM AUTHOR]

Unlike exhaust emissions, non-exhaust traffic emissions are completely unregulated and in addition, there are large uncertainties in the non-exhaust emission factors required to estimate the emissions of these aerosols. This study provides the first published results of direct measurements of size resolved emission factors for particles in the size range 0.25-2.5 µm using a new approach to derive aerosol emission factors based on carbon dioxide (CO2) emission fluxes. Aerosol fluxes were measured over one year using the eddy covariance method at the top of a 105 m high communication tower in Stockholm, Sweden. Maximum CO2 and particle fluxes were found when the wind direction coincided with the area of densest traffic within the footprint area. Negative fluxes (uptake of CO2 and deposition of particles) coincided with periods of sampling from an urban forest area. The fluxes of CO2 were used to obtain emission factors for particles by assuming that the CO2 fluxes could be directly related to the amount of fuel burnt by vehicles in the footprint area. The estimated emission factor for the fleet mix in the measurement area was, in number 1.8 x 1011 particle veh-1 km-1 (for 0.25-2.5 µm size range). Assuming spherical particles of density 1600kg m-3 this corresponds to 27.5 mg veh-1 km-1. For particles (0.8-9 2.5 µm) the emission factors were 5.1 x 109 veh-1 km-1 for number and 11.5 mg veh-1 km-1 for mass. But a wind speed dependence was noted for high wind speeds. Thus, for wind speeds larger than 9 ms-1, as measured in the tower at 105 m (U105), the emission factor for particle number and mass was parameterised as: Ef(Number, 0.8-2.5 µm) = (6.1 ± 1.7) 109U105 - 504 ± 188 and Ef(Mass, 0.8-2.5 µm) = (20 ± 12) U105 - 171 ± 122. [ABSTRACT FROM AUTHOR]

The article offers information on the postglacial (PG) fault research in Skokloster, Sweden. It states that the fault research is expected to contribute in planning for the disposal of used nuclear fuel, carbon dioxide (CO2), and toxic waste. It notes that mineral exploration and estimation of mine stability may benefit from the PG fault research. It also mentions that drilling into PG faults is considered to be a feasible scientific initiative.

The purpose of this study was to assess the applicability of civilian retention theory in the military by exploring the relationship between established determinants of retention and intentions to remain in the NZ Army. Specific hypotheses were made based on the civilian theory and these formed the basis for a preliminary military retention model. The model was then tested on 97 individuals currently enlisted in the New Zealand Army. Regression and path modeling results indicated that work satisfaction and organisational commitment are the proximal predictors of intentions to remain in the military, and that these predictors mediate the relationship between more distal predictors and retention. The results signified the relevance and usefulness of civilian research in predicting retention in the military, and future research directions are discussed. [ABSTRACT FROM AUTHOR]

This study explores the impact of clean energy and non-renewable energy consumption on CO2 emissions and economic growth within two phases (formative and expansion) of renewable energy diffusion for three selected countries (France, Spain, and Sweden). The vector autoregression (VAR) model is estimated on the basis of annual data disaggregated into quarterly data. The Granger causality results reveal distinctive differences in the causality patterns across countries and two phases of renewables diffusion. Clean energy consumption contributes to a decline of emissions more clearly in the expansion phase in France and Spain. However, this effect seems to be counteracted by the increases in emissions due to economic growth and non-renewable energy consumption. Therefore, clean energy consumption has not yet led to a decoupling of economic growth from emissions in France and Spain; in contrast, the findings for Sweden evidence such a decoupling due to the neutrality between economic growth and emissions. Generally, the findings show that despite the enormous growth of renewables and active mitigation policies, CO2 emissions have not substantially decreased in selected countries or globally. Focused and coordinated policy action, not only at the EU level but also globally, is urgently needed to overhaul existing fossil-fuel economies into low-carbon economies and ultimately meet the relevant climate targets. [ABSTRACT FROM AUTHOR]

Peatlands play an important role in the global carbon cycle as they contain a large soil carbon stock. However, current climate change could potentially shift peatlands from being carbon sinks to carbon sources. Remote sensing methods provide an opportunity to monitor carbon dioxide (CO2) exchange in peatland ecosystems at large scales under these changing conditions. In this study, we developed empirical models of the CO2 balance (net ecosystem exchange, NEE), gross primary production (GPP), and ecosystem respiration (ER) that could be used for upscaling CO2 fluxes with remotely sensed data. Two to three years of eddy covariance (EC) data from five peatlands in Sweden and Finland were compared to modelled NEE, GPP and ER based on vegetation indices from 10 m resolution Sentinel-2 MSI and land surface temperature from 1 km resolution MODIS data. To ensure a precise match between the EC data and the Sentinel-2 observations, a footprint model was applied to derive footprint-weighted daily means of the vegetation indices. Average model parameters for all sites were acquired with a leave-one-out-cross-validation procedure. Both the GPP and the ER models gave high agreement with the EC-derived fluxes (R2 = 0.70 and 0.56, NRMSE = 14% and 15%, respectively). The performance of the NEE model was weaker (average R2 = 0.36 and NRMSE = 13%). Our findings demonstrate that using optical and thermal satellite sensor data is a feasible method for upscaling the GPP and ER of northern boreal peatlands, although further studies are needed to investigate the sources of the unexplained spatial and temporal variation of the CO2 fluxes. [ABSTRACT FROM AUTHOR]