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Observation of turbulent dispersion of artificially released SO2 puffs with UV cameras
In atmospheric tracer experiments, a substance is released into the turbulent atmospheric flow to study the dispersion parameters of the atmosphere. That can be done by observing the substance's concentration distribution downwind of the source. Past experiments have suffered from the fact that observations were only made at a few discrete locations and/or at low time resolution. The Comtessa project (Camera Observation and Modelling of 4-D Tracer Dispersion in the Atmosphere) is the first attempt at using ultraviolet (UV) camera observations to sample the three-dimensional (3-D) concentration distribution in the atmospheric boundary layer at high spatial and temporal resolution. For this, during a three-week campaign in Norway in July 2017, sulfur dioxide (SO2), a nearly passive tracer, was artificially released in continuous plumes and nearly instantaneous puffs from a 9m high tower. Column-integrated SO2 concentrations were observed with six UV SO2 cameras with sampling rates of several hertz and a spatial resolution of a few centimetres. The atmospheric flow was characterised by eddy covariance measurements of heat and momentum fluxes at the release mast and two additional towers. By measuring simultaneously with six UV cameras positioned in a half circle around the release point, we could collect a data set of spatially and temporally resolved tracer column densities from six different directions, allowing a tomographic reconstruction of the 3-D concentration field. However, due to unfavourable cloudy conditions on all measurement days and their restrictive effect on the SO2 camera technique, the presented data set is limited to case studies. In this paper, we present a feasibility study demonstrating that the turbulent dispersion parameters can be retrieved from images of artificially released puffs, although the presented data set does not allow for an in-depth analysis of the obtained parameters. The 3-D trajectories of the centre of mass of the puffs were reconstructed enabling both a direct determination of the centre of mass meandering and a scaling of the image pixel dimension to the position of the puff. The latter made it possible to retrieve the temporal evolution of the puff spread projected to the image plane. The puff spread is a direct measure of the relative dispersion process. Combining meandering and relative dispersion, the absolute dispersion could be retrieved. The turbulent dispersion in the vertical is then used to estimate the effective source size, source timescale and the Lagrangian integral time. In principle, the Richardson–Obukhov constant of relative dispersion in the inertial subrange could be also obtained, but the observation time was not sufficiently long in comparison to the source timescale to allow an observation of this dispersion range. While the feasibility of the methodology to measure turbulent dispersion could be demonstrated, a larger data set with a larger number of cloud-free puff releases and longer observation times of each puff will be recorded in future studies to give a solid estimate for the turbulent dispersion under a variety of stability conditions.
2018
Tiltaksutredning for lokal luftkvalitet i Sarpsborg og Fredrikstad
Tiltaksutredningen omfatter en kartlegging av luftkvaliteten i Fredrikstad og Sarpsborg ved trafikkberegninger og utslipps- ogspredningsberegninger for PM10 og NO2 for dagens situasjon (2016) og framtidig situasjon (2022). Forurensningsnivåene er innenfor de juridiske grenseverdiene og det er ikke formelt krav til tiltak utover gjeldende handlingsplan (2017). For å redusere risikoen for overskridelser av grenseverdiene i et «ekstrem år» og generelt forbedre luftkvaliteten, er enkelte nye tiltak effektberegnet sammen med tiltak i Bypakke Nedre Glomma. Basert på resultatene fra beregningene og i samarbeid
med oppdragsgiver og prosjektgruppen, er det foreslått en revidert seks-punkts handlingsplan, med ytterligere tre tiltak for forbedret luftkvalitet utover de juridiske kravene. Tiltaksutredningen med handlingsplan skal behandles politisk.
NILU
2018
2018
2018
Air quality in Norwegian cities in 2015. Evaluation Report for NBV Main Results.
This report documents the final deliveries of the first phase of development of the Norwegian Air Quality Planning Tool,
also called “Nasjonalt Beregningsverktøy” or NBV. The main purpose of NBV is to provide a common methodological and
information platform for local air quality modelling applications. The system is addressed to local and regional
environmental authorities, air quality experts and consulting companies. It is intended to help them meet the requirements
of current air quality legislation, to support local air quality planning and facilitate air quality good practices where people live.
The report constitutes a comprehensive user guide for the NBV services available at http://www.luftkvalitet-nbv.no. It
presents each of the different products developed at NBV, documents how the product has been calculated, provides
recommendations on how best to use it for planning purposes and explains the main strengths and limitations of each
product. The report also includes an extensive validation of the air quality information currently available at NBV.
NILU
2018
Air quality in 7 Norwegian municipalities in 2015. Summary report for NBV results.
This report documents the methodology used to compile air quality information for the year 2015 in seven Norwegian municipality areas under the first phase of development of the Norwegian Air Quality Planning Tool, also called “Nasjonalt Beregningsverktøy” or NBV. It follows a similar structure to and complements the final report entitled “Air quality in 7 Norwegian municipalities in 2015 – Summary report for NBV results” (NILU rapport 21/2017) where information on air quality in the seven main city areas in Norway was presented.
This report constitutes a user guide for the NBV-services, available at http://www.luftkalitet-nbv.no, in municipal areas. It provides recommendations on how to best use each product for air quality planning purposes and explains the main strengths and limitations of the results. The NBV air quality data for municipalities is subject to larger uncertainties than the data available for the main Norwegian city areas and this has to be taken into consideration when analyzing the results.
NILU
2018
2018
2018
2018
Air quality in Europe - 2018 report
The current report presents an updated overview and analysis of air quality in Europe from 2000 to 2016. It reviews the progress made towards meeting the air quality standards established in the two EU Ambient Air Quality Directives and towards the World Health Organization (WHO) air quality guidelines (AQGs). It also presents the latest findings and estimates on population and ecosystem exposure to the air pollutants with the greatest impacts and effects. The evaluation of the status of air quality is based mainly on reported ambient air measurements, in conjunction with modelling data and data on anthropogenic emissions and their evolution over time.
European Environment Agency
2018
The 1783–1784 Laki eruption provides a natural experiment to evaluate the performance of chemistry-transport models in predicting the health impact of air particulate pollution. There are few existing daily meteorological observations during the second part of the 18th century. Hence, creating reasonable climatological conditions for such events constitutes a major challenge. We reconstructed meteorological fields for the period 1783–1784 based on a technique of analogues described in the Methods. Using these fields and including detailed chemistry we describe the concentrations of sulphur (SO2/SO4) that prevail over the North Atlantic, the adjoining seas and Western Europe during these 2 years. To evaluate the model, we analyse these results through the prism of two datasets contemporary to the Laki period: • The date of the first appearance of ‘dry fogs’ over Europe, • The excess mortality recorded in French parishes over the period June–September 1783. The sequence of appearances of the dry fogs is reproduced with a very-high degree of agreement to the first dataset. High concentrations of SO2/SO4 are simulated in June 1783 that coincide with a rapid rise of the number of deceased in French parishes records. We show that only a small part of the deceased of the summer of 1783 can be explained by the present-day relationships between PM2.5 and relative risk. The implication of this result is that other external factors such as the particularly warm summer of 1783, and the lack of health care at the time, must have contributed to the sharp increase in mortality over France recorded from June to September 1783.
2018
Prepared by Earth Observation Data Centre for Water Resources Monitoring (EODC) GmbH in cooperation with TU Wien, GeoVille, ETH Zürich, TRANSMISSIVITY, AWST, FMI, UCC and NILU
The ESA Climate Change Initiative Phase 2 Soil Moisture Project
2018
Monitoring of environmental contaminants in air and precipitation. Annual report 2017.
This monitoring report presents data from 2017 and time-trends for the Norwegian programme for Long-range atmospheric transported contaminants. The results cover 180 organic compounds and 11 heavy metals. The organic contaminants include regulated persistent organic pollutants (POPs) as
well as POP-like contaminants not yet subjected to international regulations. Five groups of new POP-like contaminants were included for the first time in 2017.
NILU
2018
2018
Pergamon Press
2018
2018
Screening Programme 2017 – AMAP Assessment Compounds
This report summarizes the findings of a screening study on the occurrence of emerging substances selected by AMAP and other related substances measured earlier. The study includes selected solvents, siloxanes, flame retardants, UV compounds, pesticides, bisphenols and other PBT compounds in effluent, ambient air, biota, and marine plastic.
NILU
2018
NILU og Urbanet Analyse har på oppdrag fra Miljødirektoratet utviklet modellen NERVE («Norwegian Emissions from Road
Vehicle Exhaust») for klimagassutslipp fra veitrafikken i norske kommuner. NERVE beregner klimagassutslipp fra
veitrafikken totalt innenfor hver kommune geografisk og for kommunens innbyggere, både som totalt utslipp og som en
utslippsfaktor (g/km). NERVE en en «bottom-up» modell som bygger på fire detaljerte datasett; 1) Veinettet ved alle
offentlige veier fra Nasjonal vegdatabank (NVDB), 2) trafikk på vei fra Regional Transport Model (RTM), 3)
kjørelengdestatistikken for norskregistrerte kjøretøy fra Statistisk Sentralbyrå Norge (SSB) og 4) utslippsfaktorer fra HBEFA(Hand Book of Emission FActors for Road Transport.
NILU
2018
2018
In birds, incubation‐related behaviors and brood patch formation are influenced by hormonal regulation such as prolactin secretion. Brood patch provides efficient heat transfer between the incubating parent and the developing embryo in the egg. Importantly, several environmental contaminants are already known to have adverse effects on avian reproduction. However, relatively little is known about the effect of contaminants on incubation temperature (Tinc) in wild birds. By using temperature thermistors placed into artificial eggs, we investigated whether the most contaminated parent birds are less able to provide appropriate egg warming and thus less committed to incubating their clutch. Specifically, we investigated the relationships among 3 groups of contaminants (organochlorines, perfluoroalkyl substances [PFASs], and mercury [Hg]) with Tinc and also with prolactin concentrations and brood patch size in incubating Arctic black‐legged kittiwakes (Rissa tridactyla). Our results reveal that among the organochlorines considered, only blood levels of oxychlordane, the main metabolite of chlordane, a banned pesticide, were negatively related to the minimum incubation temperature in male kittiwakes. Levels of PFASs and Hg were unrelated to Tinc in kittiwakes. Moreover, our study suggests a possible underlying mechanism: since we reported a significant and negative association between blood oxychlordane concentrations and the size of the brood patch in males. Finally, this reduced Tinc in the most oxychlordane‐contaminated kittiwakes was associated with a lower egg hatching probability.
Pergamon Press
2018
2018
2018