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Current estimates of carbon dioxide (CO2) evasion from Arctic lakes are highly uncertain because few studies integrate seasonal variability, specifically evasion during spring ice‐melt. We quantified annual CO2 evasion for 14 clear‐water Arctic lakes in Northern Sweden through mass balance (ice‐melt period) and high‐frequency loggers (open‐water period). On average, 80% (SD: ± 18) of annual CO2 evasion occurred within 10 d following ice‐melt. The contribution of the ice‐melt period to annual CO2 evasion was high compared to earlier studies of Arctic lakes (47% ± 32%). Across all lakes, the proportion of ice‐melt : annual CO2 evasion was negatively related to the dissolved organic carbon concentration and positively related to the mean depth of the lakes. The results emphasize the need for measurements of CO2 exchange at ice‐melt to accurately quantify CO2 evasion from Arctic lakes. [ABSTRACT FROM AUTHOR]

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]

This article examines the hypothesis of deterministic emissions convergence for a panel of the BRICS and Indonesia to advanced countries' emissions levels as well as to Sweden (which is a country that has clearly gone through decoupling) using a novel dataset with ten series of annual estimates of anthropogenic emissions comprising aerosols, aerosol precursor and reactive compounds, and carbon dioxide from 1820 to 2018. For that purpose, we employ four novel panel unit root tests allowing for several forms of time-dependent and state-dependent nonlinearity. The evidence supports deterministic convergence following a linear process for carbon dioxide, whereas the adjustment is asymmetric and nonlinear for carbon monoxide. Methane and nitrogen oxides exhibit logistic smooth transition converging dynamics. In contrast, black carbon, ammonia, nitrous oxide, non-methane volatile organic compounds, organic carbon, and sulfur dioxide emissions diverge. These results have implications for the abatement of greenhouse gases emissions at the global level, given the high share of emissions of the BRICS. [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]

In a city there are hotspots that attract citizens, and most of the transportation arises when citizens move between their residence and primary destinations (i.e. hotspots). However, an ex ante evaluation of energy-efficient mobility and urban residential planning has seldom been conducted. Therefore, this paper proposes an ex ante evaluation method to quantify the impacts, in terms of CO2emissions induced by intra-urban car mobility, of residential plans for various urban areas. The method is illustrated in a case study of a Swedish midsize city, which is presently preoccupied with urban planning of new residential areas in response to substantial population growth due to immigration. In general, CO2emissions increase from the continued urban core area (CUCA), to the sub-polycentric area (SPA), to the edge urbanization area (EUA), where CO2emission of EUA is twice that of the CUCA. The average travel distances also increase in the same pattern, though the relative increase is more than four times. Apartment buildings could be more effective in meeting residential needs and mitigating CO2emissions than dispersed single-family houses. [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]

Pre-oxygenation using high-flow nasal oxygen can decrease the risk of desaturation during rapid sequence induction in patients undergoing emergency surgery. Previous studies were single-centre and often in limited settings. This randomised, international, multicentre trial compared high-flow nasal oxygen with standard facemask pre-oxygenation for rapid sequence induction in emergency surgery at all hours of the day and night. A total of 350 adult patients from six centres in Sweden and one in Switzerland undergoing emergency surgery where rapid sequence induction was required were included and randomly allocated to pre-oxygenation with 100% oxygen using high-flow nasal oxygen or a standard tight-fitting facemask. The primary outcome was the number of patients developing oxygen saturations <93% from the start of pre-oxygenation until 1 min after tracheal intubation. Data from 349 of 350 patients who entered the study were analysed (174 in the high-flow nasal oxygen group and 175 in the facemask group). No difference was detected in the number of patients desaturating <93%, five (2.9%) vs. six (3.4%) patients in the high-flow nasal oxygen and facemask group, respectively (p = 0.77). The risk of desaturation was not increased during on-call hours. No difference was seen in end-tidal carbon dioxide levels in the first breath after tracheal intubation or in the number of patients with signs of regurgitation between groups. These results confirm that high-flow nasal oxygen maintains adequate oxygen levels during pre-oxygenation for rapid sequence induction. [ABSTRACT FROM AUTHOR]

Bringing global warming to a halt requires that worldwide net emissions of carbon dioxide be brought to essentially zero; the sooner this occurs, the less warming our descendants for the next 1000 years and more will need to adapt to. The widespread fear that the actions needed to bring this about conflict with economic growth is a major impediment to efforts to protect the climate. But much of this fear is pointless, and the magnitude of the task - while great - is no greater than the challenges that human ingenuity has surmounted in the past. To light the way forward, we need to examine success stories where nations have greatly reduced their carbon dioxide emissions while simultaneously maintaining vigorous growth in their standard of living; a prime example is Sweden. Through a combination of sensible government infrastructure policies and free-market incentives, Sweden has managed to successfully decarbonize, cutting its per capita emissions by a factor of 3 since the 1970s, while doubling its per capita income and providing a wide range of social benefits. This has all been accomplished within a vigorous capitalistic framework that in many ways better embodies free-market principles than the US economy. Consequently, the Swedish experience shows that solving global warming does not require us to "tear down capitalism." The world just needs to be a bit more like Sweden. [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]

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]

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]

Ponds are active components of the global carbon cycle processing and emitting carbon dioxide and methane to the atmosphere. These common habitats frequently experience seasonal water table variations resulting in periodically air-exposed sediments. However, the influence of these events on both the system scale carbon balance and in-pond environmental conditions remains poorly studied. We took advantage of an extraordinarily warm and dry summer to quantify the CO2 efflux from air-exposed sediments and water surfaces in desiccating ponds on Öland, Sweden. Simultaneously, we modelled metabolism and measured environmental variables within the ponds. We found that air-exposed sediments had high CO2 effluxes greatly exceeding that from the water surfaces. Sediment water content influenced the temperature and strongly regulated the CO2 efflux gradually approaching zero as water evaporated. Within the desiccating ponds, respiration was generally higher than gross primary production, but was lower compared to the same ponds with higher water table. These findings highlight the role of periodically air-exposed pond sediments as sites of highly active carbon processes. Not only is this important for the system-scale carbon in ponds, but it may also influence the destiny of buried carbon in lakes subject to climate changes. The environmental conditions within desiccating ponds, most notably high water temperatures and poor oxygen conditions, further iterate the dynamics and extreme nature of ponds. [ABSTRACT FROM AUTHOR]

Introduction: Traditional validation of umbilical cord blood samples with positive veno-arterial ΔpH and arterio-venous ΔpCO2 values confirms the source of samples, whereas negative Δvalues represent mix-up of samples. To investigate whether this is true, the distributions of V-A ΔpO2 and A-V Δlactate were also explored and related to clinical characteristics. In addition, different cord blood sampling techniques were evaluated.Material and Methods: Register study with cord blood acid-base and clinical data from 27 233 newborns. Clinical characteristics were related to positive, zero and negative Δvalues. Blood samplings from unclamped and double-clamped cords were compared. A two-sided P < 0.05 was considered significant.Results: ΔpH and ΔpCO2 values distributed into positive, around zero, and negative sub-populations, with significant differences in pH and clinical characteristics between sub-populations. No such sub-populations were distinguished for ΔpO2 and Δlactate. The 2.5th and 5th ΔpH percentiles were 0.013 and 0.022, respectively, and for ΔpCO2 0.30 and 0.53 kPa. Applying 5th percentile criteria resulted in 3.5% of "approved" cases showing a ΔpO2  ≤ 0. Puncture and sampling of the unclamped cord resulted in significantly better sample quality.Conclusions: Unphysiological negative ΔpO2 values occurred despite correct validation with traditional criteria. Δlactate cannot be used for validation because both positive and negative values are physiological. Positive/around zero/negative ΔpH and ΔpCO2 sub-populations were associated with significant differences in pH and clinical characteristics, indicating that defective sampling and sample handling are not the sole explanations for negative Δvalues. Prompt puncture and sampling of the unclamped cord resulted in best sample quality. [ABSTRACT FROM AUTHOR]

This paper investigates the greenhouse gas emissions from a Swedish wetland, constructed to decrease nutrient content in sewage treatment water. To evaluate the effect of the construction in terms of greenhouse gas emissions we carried out ecosystem-atmosphere flux measurements of CO2, CH4 and N2O using a closed chamber technique. To evaluate the importance of vascular plant species composition to gas emissions we distributed the measurement plots over the three dominating plant species at the field site, i. E. , Typha latifolia, Phragmites australis and Juncus effusus. The fluxes of CO2 (total respiration), CH4 and N2O from vegetated plots ranged from 1. 39 to 77. 5 (g m−2 day−1), −377 to 1387 and −13. 9 to 31. 5 (mg m−2 day−1) for CO2, CH4 and N2O, respectively. Presence of vascular plants lead as expected to significantly higher total respiration rates compared with un-vegetated control plots. Furthermore, we found that the emission rates of N2O and CH4 was affected by presence of vascular plants and tended to be species-specific. We assessed the integrated greenhouse warming effect of the emissions using a Global Warming Potential over a 100-year horizon (GWP100) and it corresponded to 431 kg CO2 equivalents m−2 day−1. Assuming a 7-month season with conditions similar to the study period this is equal to 90 tonnes of CO2 equivalents annually. N2O emissions were responsible for one third of the estimated total greenhouse forcing. Furthermore, we estimated that the emission from the forested bog that was the precursor land to Magle constructed wetland amounted to 18. 6 tonnes of CO2 equivalents annually. Hence, the constructed wetland has increased annual greenhouse gas emissions by 71. 4 tonnes of CO2 equivalents for the whole area. Our findings indicate that management processes in relation to wetland construction projects must consider the primary function of the wetland in decreasing eutrophication, in relation to other positive aspects on for instance plant and animal life and recreation as well as possible negative climatic aspects of increased emissions of CH4 and N2O. [ABSTRACT FROM AUTHOR]

Under changing climatic conditions permafrost peatlands can play an important role in the global carbon budget through permafrost carbon feedbacks and shifts in carbon assimilation. To better predict future dynamics in these ecosystems an increased understanding of their Holocene carbon and permafrost history is needed. In Tavvavuoma, northern Sweden, we have performed detailed analyses of vegetation succession and geochemical properties at six permafrost peatland sites. Peatland initiation took place around 10 000 to 9600 cal. a BP, soon after retreat of the Fennoscandian Ice Sheet, and the peatlands have remained permafrost‐free fens throughout most of the Holocene. At the four sites that showed a continuous accumulation record during the late Holocene radiocarbon dating of the shift from wet fen to dry bog vegetation, characteristic of the present permafrost peatland surface, suggests that permafrost developed at around 600–100 cal. a BP. At the other two sites peat accumulation was halted during the late Holocene, possibly due to abrasion, making it more difficult to imply the timing of permafrost aggradation. However also at these sites there are no indications of permafrost inception prior to the Little Ice Age. The mean long‐term Holocene carbon accumulation rate at all six sites was 12.3±2.4 gC m−2 a−1 (±SD), and the mean soil organic carbon storage was 114±27 kg m−2. [ABSTRACT FROM AUTHOR]

This study undertakes a decomposition analysis to identify the drivers of carbon dioxide emissions change in the Swedish business and industry sectors 1993–2006. On aggregate, energy intensity decreased, but this does not seem to have been very important for reducing emissions. Rather, fuel substitution seems to have been more important, which is in line with findings from the decomposition literature on Sweden. However, at the sectoral level, we find no clear pattern of the effect of fuel substitution and energy intensity on emissions. We also draw some methodological conclusions: decomposition analysis should be undertaken at the most disaggregate level possible; assessing decomposition results by summing results over several time periods leads to biased results; and decomposition analysis should not be based only on some initial and final years of a long time period. Furthermore, we address the problem of double counting energy flows in decomposition analysis of aggregate effects when the energy sector is included, and point out potential problems related to output measured in monetary terms. [ABSTRACT FROM AUTHOR]

Background: Gas microembolisation is an identified risk in cardiac surgery. Flooding the wound with carbon dioxide is a method proposed to reduce this problem. The high solubility of carbon dioxide is beneficial, but may also cause problems. The gas solubility diminishes at warming and endogenous bubbles are formed when cold blood saturated with carbon dioxide is returned by cardiotomy suction. Methods: The release of endogenous gas was measured at high resolution in an experimental digital model. A medium (water or blood) was incubated and equilibrated with gas (100% carbon dioxide or air) at a low temperature (10ºC or 23ºC). The temperature was increased to 37ºC and the gas release was measured, at rest and at fluid motion. Results: The amount of carbon dioxide released at warming was substantial for both water and blood (both p=0.005). The effect was more pronounced when the temperature differential increased (p=0.005). However, blood and water differed in these terms: with water, the release of carbon-dioxide started instantly at warming; with blood, carbon dioxide remained dissolved and was released at fluid motion. When blood was warmed from 10ºC to 37ºC, the gas release corresponded to 44.4% (40.6/46.5) of the medium volume (median with quartile range). Conclusion: Gas dissolved in a medium becomes released at warming, as confirmed here. Blood exposed to carbon dioxide became heavily oversaturated at warming, with the gas instantly released at fluid motion. The amount of contained gas increased with a higher temperature differential. Our study has relevance to wound flushing, using carbon dioxide, in cardiac surgery. The clinical consequences of these findings remain to be answered. [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]

SUMMARY Road transport is responsible for a large and growing share of CO2 emissions in most countries. A number of new fuel-efficient vehicle technologies and renewable transport fuels are possible alternatives to conventional options but their deployment relies strongly on different policy measures. Even though a future higher use of transport biofuels and electric vehicles is likely to increase the interaction between the transportation sector and the stationary energy system (heat, power, etc.), these systems are often analysed separately. In this study, a transport module is developed and integrated into the MARKAL_Nordic energy system model. The transport module describes a range of vehicle technologies and fuel options as well as different paths for conversion of primary energy resources into transport fuels. The integrated model is utilized to analyse the impact of transport fuel tax designs on future cost-effective fuel and technology choices in the Swedish transportation sector, as well as the consequences of these choices on system costs and CO2 emissions. The model, which is driven by cost-minimization, is run to 2050 with various assumptions regarding transport fuel tax levels and tax schemes. The results stress the importance of fuel taxes to accelerate the introduction of fuel-efficient vehicle technologies such as hybrids and plug-in hybrids. Tax exemptions can make biofuels an economically favourable choice for vehicle users. However, due to limitations in biomass supply, a too strong policy-focus on transport biofuels can lead to high system costs in relation to the CO2 abatement achieved. The modelling performed indicates that the effects caused by linkages between the transportation sector and the stationary energy system can be significant and integrated approaches are thus highly relevant. Copyright © 2011 John Wiley & Sons, Ltd. [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.

We tested the hypothesis that CO2 supersaturation along the aquatic conduit over Sweden can be explained by processes other than aquatic respiration. A first generalized-additive model (GAM) analysis evaluating the relationships between single water chemistry variables and pCO2 in lakes and streams revealed that water chemistry variables typical for groundwater input, e.g., dissolved silicate (DSi) and Mg2+ had explanatory power similar to total organic carbon (TOC). Further GAM analyses on various lake size classes and stream orders corroborated the slightly higher explanatory power for DSi in lakes and Mg2+ for streams compared with TOC. Both DSi and TOC explained 22–46% of the pCO2 variability in various lake classes (0.01–>100 km2) and Mg2+ and TOC explained 11–41% of the pCO2 variability in the various stream orders. This suggests that aquatic pCO2 has a strong groundwater signature. Terrestrial respiration is a significant source of the observed supersaturation and we may assume that both terrestrial respiration and aquatic respiration contributed equally to pCO2 efflux. pCO2 and TOC concentrations decreased with lake size suggesting that the longer water residence time allow greater equilibration of CO2 with the atmosphere and in-lake mineralization of TOC. For streams, we observed a decreasing trend in pCO2 with stream orders between 3 and 6. We calculated the total CO2 efflux from all Swedish lakes and streams to be 2.58 Tg C yr−1. Our analyses also demonstrated that 0.70 Tg C yr−1 are exported to the ocean by Swedish watersheds as HCO3− and CO32− of which about 0.56 Tg C yr−1 is also a residual from terrestrial respiration and constitute a long-term sink for atmospheric CO2. Taking all dissolved inorganic carbon (DIC) fluxes along the aquatic conduit into account will lower the estimated net ecosystem C exchange (NEE) by 2.02 Tg C yr−1, which corresponds to 10% of the NEE in Sweden. [ABSTRACT FROM AUTHOR]

This study investigates the effect of a CO2 tax on profitability by using firm-level data on output and inputs from Swedish industry between 1990 and 2004. The purpose of this exercise is to investigate the validity of the so-called Porter hypothesis. By utilizing a factor-demand modeling approach, and specifying a profit function that has a technology component dependent upon firm-specific effective tax on CO2, we are able to separate out the effect of regulatory pressure on technological progress. The results indicate that there is evidence of a “reversed” Porter effect in most industrial sectors, especially in energy-intensive industries; that is, after controlling for the fuel price effect, technological progress and consequently profits are further negatively affected by the CO2 tax. [ABSTRACT FROM AUTHOR]

We report an analysis of both the long- and short-term drivers of the carbon (C) isotope composition ( δ13C) values of current year needles of Pinus sylvestris L. linked to changing atmospheric carbon dioxide (CO2) concentrations ( ca) and climate using data from a uniquely long-term nitrogen (N) fertilization experiment in the north of Sweden (consisting of three N dosage levels and a control treatment) from 1970 until 2002. N loading produced trees with less negative δ13C of foliage, by around 0.45‰ on average, with the difference in δ13C between control and N treatments not dependant upon N dosage. The average δ13C values decreased at a rate of around 0.03‰ yr−1, even after accounting for the Suess effect (the decrease in the atmospheric CO2 δ13C due to anthropogenic emissions of isotopically light CO2). This decrease is large enough to cause a significant, progressive change in the δ13C down through a soil profile. Modelled values of plant intrinsic water use efficiency (WUEi) and the ratio of leaf internal to external [CO2] ( ci/ ca) showed that this was the result of ci increasing in parallel with ca (while ci/ ca increased), thus causing little change in WUEi over the 32 years of study. The residuals from the relationships between year and δ13C were used to examine the impact of climate on the interannual variation of C isotope composition of needles. This included the use of a fire hazard index (FHI) model, which integrates climatic factors known to influence plant stomatal conductance and hence δ13C. The FHI produced the best fit with δ13C values when climate data were averaged over the whole growth season (for control plots) and for July for all the N treatments, explaining ca. 60% of the total interannual variation in δ13C. Further, trees from the N treatments appeared more susceptible to air-humidity-based climate parameters, as seen from higher correlation coefficients, than were control trees. Thus, our data suggest the possibility of increased susceptibility to drought conditions in ecosystems with moderate to high N deposition rates. Also, there is the possibility that, because there was no apparent change in WUEi of P. sylvestris in this ecosystem over the last 32 years, the rate of sequestration of C into boreal ecosystems may not increase with ca, as has been predicted. [ABSTRACT FROM AUTHOR]

The main objective of this study is to improve the modelling of household demand for transport services in a Computable General Equilibrium (CGE) model. The new extended model is then used for numerical calculations to test how the Swedish economy reacts to a carbon target. Special attention will be given to distributional effects and the connection between labour supply and work journeys in a sparsely populated country like Sweden. A differentiation between trip purposes and trip length, a complementary relationship between work journeys and labour supply, and a subdivision of households by density of population and income influence the numerical results. Our main conclusions from the analysis of a carbon target are that if the carbon tax revenue is recycled by decreasing the employers’ social contribution fee, welfare costs are lower than with lump-sum replacements of tax revenue to households. The welfare cost may be reduced even further if work journeys are not additionally taxed as compared to the base year. However, the lower total welfare cost is obtained at the expense of making society more unequal, since both labour tax recycling (cuts in employers’ social contributions) and exempting tax on work journeys will make low income groups carry a higher burden. An increased carbon dioxide tax is also shown to increase welfare differences between sparsely populated areas and city regions in Sweden. [ABSTRACT FROM AUTHOR]

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]

Control of CO2 emissions is a major environmental issue in most countries. The Swedish car market shows remarkably low new Diesel passenger car registrations compared to the average European Union car market. Therefore, a simple way to decrease CO2 emissions from the transport sector in Sweden would be the replacement of gasoline by Diesel passenger cars, which emit less CO2. The combined effects of probable changes in Diesel and gasoline future fuel consumption, new passenger car sales and market segmentation have been evaluated for different Diesel passenger cars penetrations. The results show a benefit in CO2 emissions of about 2.8% with 30% Diesel penetration; if Diesel penetration reaches 50%, the benefit attains 7.5%. Future rises of CO2 emissions caused by higher new passenger car registrations or unfavourable market segmentation could be at least partially counterbalanced by the introduction of more Diesel passenger cars. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The objective of this study was to estimate the contribution of drained organic forestlands in Sweden to the national greenhouse gas budget. Drained organic forestland in Sweden collectively comprises an estimated net sink for greenhouse gases of -5.0 Mt carbon dioxide (CO 2 ) equivalents year -1 (range -12.0 to 1.2) when default emission factors provided by the Good practice guidance for land use, land-use change and forestry are used, and an estimated net source of 0.8 Mt CO 2 equivalents year -1 (range -6.7 to 5.1) when available emission data for the climatic zones spanned by Sweden are used. This discrepancy is mainly due to differences in the emission factors for heterotrophic respiration. The main uncertainties in the estimates are related to carbon changes in the litter pool and releases of soil CO 2 and nitrous oxide. [ABSTRACT FROM AUTHOR]

SummaryMeasurements of the spatial variability of methane (CH4) emissions, net CO2 ecosystem exchange (NEE), and dissolved carbon (CH4, CO2, and DOC) were made in a boreal patterned peatland in northern Sweden in the summers (May to September) of 1992 and 1993. Carbon balance terms were measured and the carbon balance inferred at different peatland surface topography features (e.g. ridges, lawns, and pools) and at different positions within the peatland (e.g. plateau, margin). Combining these data permits a comparison of the carbon balance at the peatland scale for the two field seasons. Trends in the spatial variability of the net carbon storage, as determined by the difference between inputs and outputs, suggest that carbon storage decreased in lawns from the margin of the peatland to the central plateau, while the reverse trend occurred in ridges. This indicates a difference in carbon exchange processes between sites with different surface topography due to differences in soil moisture and temperature. Total carbon storage for the peatland, weighted for topographic variability, indicates that the peatland gained carbon in 1992 (2.0 g C m- 2), but lost carbon in 1993 ( - 7.6 g C m- 2). There was little variation in mean seasonal air temperature and total precipitation between the two years suggesting that the timing and magnitude of temperature and precipitation variation within the growing season are important for the season carbon balance. Because the carbon storage differences were small relative to the potential errors we conclude that the peatland was neither a net sink nor source of atmospheric carbon. This research demonstrates the importance of position in a peatland for the inference of long-term carbon accumulation and the assessment of contemporary exchange rates. [ABSTRACT FROM AUTHOR]

In this study, we tested the hypothesis that elevated [CO2] shortens the cell cycle in meristems of Dactylis glomerata, more in a Portuguese population (38°53'N) than in a Swedish population (63°09'N). In the shoot meristem, the cell cycle shortened to about the same extent (≈ 26%) in both populations exposed to the elevated [CO2] treatment. In the root meristem, the cell cycle shortened by 17% in the Portuguese and by 8% in the Swedish population. However, the proportion of rapidly cycling cells increased in the Portuguese much more than in the Swedish population in both meristems. In the root meristem, there was a 1.86-fold increase in the Portuguese compared with a 1.31- fold increase in the Swedish. In the shoot meristem, the increases were 1.5-3-fold for the Portuguese and 1.2-fold for the Swedish. The data are consistent in showing that a major response to the elevated [CO2] treatment was an increase in the proportion of cells that were cycling and that this was more marked for the Portuguese population. A more general response to the elevated [CO2] treatment was a shortening of the cell cycle regardless of population. [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]