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Regionalized environmental impacts of construction machinery
PURPOSE:
This study aims to establish a regionalized environmental impact assessment of construction machinery equipped with diesel engines certified by the European emission standard Stage V, and operated in cold climatic zones in Europe.
METHOD:
The study quantifies potential environmental impacts associated with construction machinery over the entire lifecycle, from extraction of materials to the end-of-life. For the operation phase, a meso-level emission accounting method is applied to quantify tailpipe emissions for certain subcategories of construction machinery. This is achieved by determining the operational efficiency of each machine in terms of effective hours. The quantified emission data are then adjusted based on engine deterioration models to estimate the rate of increase in emissions throughout the lifetime of each machine. Finally, the CML impact assessment method is applied to inventory data to quantify potential environmental impacts.
RESULTS:
The study shows that tailpipe emissions, which largely depend on an engine’s fuel consumption, had the largest contribution to environmental impacts in most impact categories. At the same time, there was a positive correlation between the operation weight and the impacts of the machinery. Also, machinery with similar operation weight had relatively similar impact patterns due to similar driving factors and dependencies. In addition, network, sensitivity, and uncertainty analyses were performed to quantify the source of impacts and validate the robustness of the study. Results of the sensitivity analysis showed that the responsiveness of the studied systems is very sensitive to changes in the amount of fuel consumption. In addition, the uncertainty results showed that the domain of uncertainty increased as the operation weight subcategory of machinery increased.
CONCLUSION:
This study extends previous work on the life cycle assessment (LCA) of construction machinery, and the methodology developed provides a basis for future extension and improvement in this field. The use of effective hours as the unit of operational efficiency helps to resolve uncertainties linked to lifetime and annual operation hours. Also, the obtained results can be of use for decision support and for assessing the impacts of transition from fossil fuels to alternative fuel types.
2020
2020
2020
It is unclear whether the Eurasian snow plays a role in the tropospheric driving of sudden stratospheric warming (SSW). The major SSW event of February 2018 is analyzed using reanalysis datasets. Characterized by predominant planetary waves of zonal wave 2, the SSW developed into a vortex split via wave–mean flow interaction. In the following two weeks, the downward migration of zonal-mean zonal wind anomalies was accompanied by a significant transition to the negative phase of the North Atlantic Oscillation, leading to extensive cold extremes across Europe. Here, we demonstrate that anomalous Siberian snow accumulation could have played an important role in the 2018 SSW occurrence. In the 2017/18 winter, snow depths over Siberia were much higher than normal. A lead–lag correlation analysis shows that the positive fluctuating snow depth anomalies, leading to intensified “cold domes” over eastern Siberia (i.e., in a region where the climatological upward planetary waves maximize), precede enhanced wave-2 pulses of meridional heat fluxes (100 hPa) by 7–8 days. The snow–SSW linkage over 2003–19 is further investigated, and some common traits among three split events are found. These include a time lag of about one week between the maximum anomalies of snow depth and wave-2 pulses (100 hPa), high sea level pressure favored by anomalous snowpack, and a ridge anchoring over Siberia as precursor of the splits. The role of tropospheric ridges over Alaska and the Urals in the wave-2 enhancement and the role of Arctic sea ice loss in Siberian snow accumulation are also discussed.
American Meteorological Society (AMS)
2020
Energetic particle precipitation is one of the main processes by which the sun influences atmospheric composition and structure. The polar middle atmosphere is chemically disturbed by the precipitation-induced production of nitric oxides (NOx) and hydrogen oxides (HOx) and the associated ozone (O3) loss, but the importance for the dynamics is still debated. The role of precipitating medium energy electrons (MEEs), which are able to penetrate into the mesosphere, has received increased attention, but has only recently begun to be incorporated in chemistry-climate models. We use the NCAR Whole Atmosphere Community Climate Model (WACCM) to study the climate impact from MEE precipitation by performing two idealized ensemble experiments under pre-industrial conditions, with and without the MEE forcing, over the period of the solar cycle 23 (only full calendar years, 1997–2007). Each experiment includes 20 11-year ensemble members, total 220 years. Our results indicate a strong month-to-month variability in the dynamical response to MEE throughout the winter period. We find a strengthening of the polar vortex in the northern hemisphere during December, but the signal decays rapidly in the following months. The polar vortex strengthening is likely attributable to planetary wave reduction due to increased zonal symmetries in upper stratospheric ozone heating, initially triggered by MEE-induced NOx advected into the sunlit regions. We also find a similar early winter polar vortex strengthening in the southern hemisphere during June. Changes in mean meridional circulation accompany these anomalous wave forcings, leading to dynamically-induced vertical temperature dipoles at high latitudes. The associated weakening of the stratospheric mean meridional circulation results in an upper stratospheric polar ozone deficit in early winter. This polar cap ozone deficit is strongest in the southern hemisphere and contributes to a polar vortex weakening in late winter, in concert with increased planetary wave forcing. In both hemispheres, the stratospheric polar vortex signal seems to migrate downwards into the troposphere and to the surface.
Elsevier
2020
A schematic sampling protocol for contaminant monitoring in raptors
Birds of prey, owls and falcons are widely used as sentinel species in raptor biomonitoring programmes. A major current challenge is to facilitate large-scale biomonitoring by coordinating contaminant monitoring activities and by building capacity across countries. This requires sharing, dissemination and adoption of best practices addressed by the Networking Programme Research and Monitoring for and with Raptors in Europe (EURAPMON) and now being advanced by the ongoing international COST Action European Raptor Biomonitoring Facility. The present perspective introduces a schematic sampling protocol for contaminant monitoring in raptors. We provide guidance on sample collection with a view to increasing sampling capacity across countries, ensuring appropriate quality of samples and facilitating harmonization of procedures to maximize the reliability, comparability and interoperability of data. The here presented protocol can be used by professionals and volunteers as a standard guide to ensure harmonised sampling methods for contaminant monitoring in raptors.
Springer
2020
2020
2020
This report presents VOC (volatile organic compound) measurements carried out during 2018 at EMEP monitoring sites. In total, 20 sites reported VOC-data from EMEP VOC sites this year. Some of the data-sets are considered preliminary and are not included in the report.
The monitoring of NMHC (non-methane hydrocarbons) has become more diverse with time in terms of instrumentation. Starting in the early 1990s with standardized methods based on manual sampling in steel canisters with subsequent analyses at the lab, the methods now consist of a variety of instruments and measurement principles, including automated continuous monitors and manual flask samples. For oxygenated VOCs (OVOCs), sampling in DNPH-tubes with subsequent lab-analyses is still the only method in use at EMEP sites.
Within the EU infrastructure project ACTRIS-2, data quality issues related to measurements of VOC have been an important topic. Many of the institutions providing VOC-data to EMEP have participated in the ACTRIS-2 project, either as formal partners or on a voluntary basis. Participation in ACTRIS-2 has meant an extensive effort with data-checking including detailed discussions between the ACTRIS community and individual participants. There is no doubt that this extensive effort has benefited the EMEP-program and has led to improved data quality in general.
Comparison between median levels in 2018 and the medians of the previous 10-years period, revealed a similar north-to-south pattern for several species.
Changes in instrumentation, procedures, station network etc. during the last two decades make it difficult to provide a rigorous and pan-European assessment of long-term trends of the observed VOCs. In this report, we have estimated the long-term trends in NMHC over the 2000-2018 period at six sites by two independent statistical methods. These estimates indicate marked differences in the trends for the individual species. Small or non-significant trends were found for ethane over this period followed by propane which also showed fairly small reductions. On the other hand, components linked to road traffic (ethene, ethyne and benzene) showed the strongest drop in mean concentrations, up to 60-80% at some stations.
The persistent heatwave in summer 2018 in northern and central Europe lead to higher isoprene-levels than normal. The data indicate a clear relationship between isoprene and afternoon temperature at the sites. An exponential fit is seen to be well suited for the relationship between isoprene and temperature.
NILU
2020
Air quality mitigation in European cities: Status and challenges ahead
Cities are currently at the core of air quality (AQ) improvement. The present work provides an overview of AQ management strategies and outcomes in 10 European cities (Antwerp, Berlin, Dublin, Madrid, Malmö, Milan, Paris, Plovdiv, Prague, Vienna) in 2018, and their evolution since 2013 (same cities, plus Ploiesti and Vilnius), based on first-hand input from AQ managers. The status of AQ mitigation in 2018, and its evolution since 2013, were assessed. While results evidenced that the majority of mitigation strategies targeted road traffic, emerging sources such as inland shipping, construction/demolition and recreational wood burning were identified. Several cities had in 2018 the ambition to continue decreasing air pollution concentrations to meet WHO guidelines, an ambition which had not yet been identified in 2013. Specific needs identified by all of the cities assessed were tools to quantify the effectiveness of mitigation strategies and for cost-benefit analysis, as well as specific and up to date technical guidance on real-world road vehicle emissions. The cities also requested guidance to identify mitigation measures promoting co-benefits, e.g., in terms of AQ, climate change, and noise. Support from administrations at local-regional-national-EU scales, and especially involving local policy-makers early on in the air quality management process, was considered essential. This work provides insight into the drivers of successful/unsuccessful AQ policies as well as on the challenges faced during their implementation. We identify knowledge gaps and provide input to the research and policy-making communities as to specific needs of cities.
Elsevier
2020
Polycyclic aromatic hydrocarbons (PAHs) are not
declining in Arctic air despite reductions in their global emissions.
In Svalbard, the Longyearbyen coal-fired power plant
is considered to be one of the major local sources of PAHs.
Power plant stack emissions and ambient air samples, collected
simultaneously at 1 km (UNIS) and 6 km (Adventdalen)
transect distance, were analysed (gaseous and particulate
phases separately) for 22 nitro-PAHs, 8 oxy-PAHs,
and 16 parent PAHs by gas chromatography in combination
with single quadrupole electron capture negative ionization
mass spectrometry (GC-ECNI-MS) and gas chromatography
in combination with triple quadrupole electron ionization
mass spectrometry (GC-EI-MS/MS). Results confirm low
levels of PAH emissions (Sum 16 PAHs D 1:5 μg/kg coal)
from the power plant. Phenanthrene, 9,10-anthraquinone, 9-
fluorenone, fluorene, fluoranthene, and pyrene accounted for
85% of the plant emission (not including naphthalene). A dilution
effect was observed for the transect ambient air samples:
1.26+/- 0.16 and 0.63+/- 0.14 ng/m3 were the sum of all
47 PAH derivatives for UNIS and Adventdalen, respectively.
The PAH profile was homogeneous for these recipient stations
with phenanthrene and 9-fluorenone being most abundant.
Multivariate statistical analysis confirmed coal combustion
and vehicle and marine traffic as the predominant
sources of PAHs. Secondary atmospheric formation of 9-
nitroanthracene and 2C3-nitrofluoranthene was evaluated
and concluded. PAHs partitioning between gaseous and particulate
phases showed a strong dependence on ambient temperatures
and humidity. The present study contributes important
data which can be utilized to eliminate uncertainties in
model predictions that aim to assess the extent and impacts
of Arctic atmospheric contaminants.
2020
Urban air pollution is a challenge in several European cities. For most Norwegian cities, the major challenge is the reduction of the NO2 annual mean concentration in order to comply with the limit value in the European Directive 2008/50/EC, but also too many high NO2 hourly values occur during strong inversions in cold winter periods. In Oslo, the main contributor to NO2 concentration levels is diesel exhaust and hence the proposed measures in this study are targeting road traffic. An extensive array of individual and grouped measures were constructed and we studied the change in traffic and NO2 concentrations by performing consecutive modelling studies which included traffic, emissions, and dispersion models. These measures were intended for permanent and temporary action. They included increases of the tolls that give access to the inner parts of the city, the establishment of low emission zones (LEZs), allowing for temporary free public transport, odd-even driving, defining priority lanes for low emission vehicles, and imposing higher parking fees. We concluded that the most efficient measures were the creation of LEZs and the increase of parking fees. We also explain how the findings from this work have helped to implement Norwegian air quality control policies.
Elsevier
2020
2020