Emission database for global atmospheric research (Edgar)

Atmospheric chemistry and climate modellers require gridded global emissions data as input into their models. To meet this urgent need a global emissions source database called EDGAR is being developed by TNO and RIVM to estimate for 1990, on a regional and on a grid basis, annual emissions of greenhouse gases (CO₂, CH₄, N₂O, CO, NO_x, non-methane VOC, SO_x), of NH₃, and of ozone depleting compounds (halocarbons) from all known sources. The aim is to establish at due levels of spatial, temporal and source aggregation the emissions from both anthropogenic and biogenic sources: a complete set of data required to estimate the total source strength of the various gases with a 1×1 ° resolution (altitude resolution of 1 km) and a temporal resolution of a month, supplemented by diurnal variation, as agreed upon in the Global Emissions Inventory Activity (GEIA) of the International Atmospheric Chemistry Programme (IGAC). In this way EDGAR will meet the requirements of present and future developments in the field of atmospheric modelling. The data comprise demographic data, social and economic factors, land use distributions and emission factors (with due emphasis on the uncertainty). As understanding in this field is still changing, due attention is paid to flexibility regarding the disaggregation of sources, spatial and temporal resolution and species. The objective and methodology chosen for the construction of the database and the structural design of the database system are presented, as well as the type and sources of data and the approach used for data collection. As an example, the construction of the N₂O inventory is discussed.     

Study of urban atmospheric pollution in Navarre (Northern Spain)

An ambient air quality study was undertaken in two cities (Pamplona and Alsasua) of the Province of Navarre in northern Spain from July 2001 to June 2004. The data were obtained from two urban monitoring sites. At both monitoring sites, ambient levels of ozone, NO_x, and SO₂ were measured. Simultaneously with levels of PM₁₀ measured at Alsasua (using a laser particle counter), PM₁₀ levels were also determined at Pamplona (using a beta attenuation monitor). Mean annual PM₁₀ concentrations in Pamplona and Alsasua reached 30 and 28 μg m⁻³, respectively. These concentrations are typical for urban background sites in Northern Spain. By using meteorological information and back trajectories, it was found that the number of exceedances of the daily PM₁₀ limit as well as the PM₁₀ temporal variation was highly influenced by air masses from North Africa. Although North African transport was observed on only 9% of the days, it contributed the highest observed PM₁₀ levels. Transport from the Atlantic Ocean was observed on 68% of the days; transport from Europe on 13%; low transport and local influences on 7%; and transport from the Mediterranean region on 3% of the days. The mean O₃ concentrations were 45 and 55 μg m⁻³ in Pamplona and Alsasua, respectively, which were above the values reported for the main Spanish cities. The mean NO and NO₂ levels were very similar in both sites (12 and 26 μg m⁻³, respectively). Mean SO₂ levels were 8 μg m⁻³ in Pamplona and 5 μg m⁻³ in Alsasua. Hourly levels of PM₁₀, NO and NO₂ showed similar variations with the typically two coincident maximums during traffic rush hours demonstrating a major anthropogenic origin of PM₁₀, in spite of the sporadic dust outbreaks.     

焦炉废气中苯可溶物(BSO)测定过程中的问题探讨

根据现有国家标准方法,本文主要针对苯可溶物(BSO)测定过程中的滤膜折叠前后质量变化等问题进行讨论,并提出处理方法。     

Characteristics and sources of atmospheric polycyclic aromatic hydrocarbons (PAHs) in Shanghai, China

A field campaign was conducted to measure and analyze 13 polycyclic aromatic hydrocarbons (PAHs) in six major zones in the city of Shanghai, P.R. China from August 2006 to April 2007. Ambient air samples were collected seasonally using passive air samplers, and gas chromatography–mass spectroscopy was used in this field campaign. The results showed that there was a sequence of 13 PAHs at Phen > FA > Pyr > Chr > Fl > An > BaA > BbFA > BghiP > IcdP > BkFA > BaP > DahA and the sum of these PAHs is 36.01 ± 10.85 ng/m³ in gas phase. FL, Phen, FA, Pyr, and Chr were the dominant PAHs in gas phase in the city. They contributed 90% of total PAHs in the gas phase. Proportion of measured PAHs with three, four, five, and six rings to total PAHs was 53%, 42%, 3%, and 2%, respectively. The highest concentration of ΣPAHs (the sum of 13 PAHs) occurred in the wintertime and the lowest was in the summer. This investigation suggested that traffic, wood combustion, and metal scrap burn emissions were dominant sources of the concentrations of PAHs in six city zones compared with coal burning and industry emissions. Further, the traffic emission sources of PAHs in the city were attributed mostly to gasoline-powered vehicles compared with diesel-powered vehicles. It was revealed that the seasonal changes in PAHs in the city depended on different source types. Metal scrap burn was found to be the major source of PAHs during the autumn, while the PAH levels in the atmosphere for winter and spring seasons were mainly influenced by wood and biomass combustion. Comparisons of PAHs among different city zones and with several other cities worldwide were also made and discussed.     

Polycyclic aromatic hydrocarbons (PAHs) in atmospheric urban area: monitoring on various types of sites

The air quality over the Toulouse urban area (France) is recorded daily by the regional "Midi-Pyrénées" atmospheric pollution measurements network (ORAMIP). Relevant data is collected from about 100 analysers spread over more than thirty stations. The regulations covering major indicators of atmospheric pollution (ozone, nitrogen dioxide, sulphur dioxide) have been updated in recent years to include additional compounds like polycyclic aromatic hydrocarbons (PAHs). The ORAMIP, in partnership with the ENSIACET has undertaken background PAH average concentration measurements over the urban agglomeration of Toulouse during spring 2006 for various types of sites (traffic, urban, industrial). The sampling was performed using a low volume air sampler equipped with quartz fiber filters and polyurethane foams For the two urban sites, total atmospheric concentrations between 12 and 20 ng/m(3) have been obtained, whereas for the industrial site the values averaged 22 ng/m(3). In addition, and regardless of site, the average concentrations of benzo[a]pyrene, at present the only regulated PAH, were always less than the 1 ng/m(3) limit.     

Spatio-temporal variations of organic carbon and chlorophyll degradation products in the surficial sediments of Izmir Bay (Aegean Sea/Turkey)

The aim of this research is to determine the effects of Izmir Big Channel Waste Water Treatment Project on the sediment quality of Izmir Bay. Wastewater treatment improves the water quality. However, sediment does not respond to this treatment as fast as water column. Monitoring of bottom water and sediment quality is necessary for identification of the recovery of the whole ecosystem. For this purpose, bottom water and sediment samples were collected from three stations which are located in the middle and inner parts of the Izmir Bay on a monthly basis between January 2003 and December 2003. Values measured at stations ranged between; 0.54-12.82 microg/L for chlorophyll-a, 0.09-9.32 microg/L for phaeopigment, 0.05-1.91 mg/L for particulate organic carbon in bottom waters, 11.88-100.29 microg/g for chlorophyll degradation products and 1.12-5.39% for organic carbon in sediment samples. In conclusion, it was found that grazing activity explained carbon variations in sediment at station 2, but at station 1 and station 3 carbon variations in sediment were not related to autochthonous biological processes.     

Mathematical models for accurate prediction of atmospheric visibility with particular reference to the seasonal and environmental patterns in Hong Kong

Atmospheric visibility impairment has gained increasing concern as it is associated with the existence of a number of aerosols as well as common air pollutants and produces unfavorable conditions for observation, dispersion, and transportation. This study analyzed the atmospheric visibility data measured in urban and suburban Hong Kong (two selected stations) with respect to time-matched mass concentrations of common air pollutants including nitrogen dioxide (NO(2)), nitrogen monoxide (NO), respirable suspended particulates (PM(10)), sulfur dioxide (SO(2)), carbon monoxide (CO), and meteorological parameters including air temperature, relative humidity, and wind speed. No significant difference in atmospheric visibility was reported between the two measurement locations (p > or = 0.6, t test); and good atmospheric visibility was observed more frequently in summer and autumn than in winter and spring (p < 0.01, t test). It was also found that atmospheric visibility increased with temperature but decreased with the concentrations of SO(2), CO, PM(10), NO, and NO(2). The results showed that atmospheric visibility was season dependent and would have significant correlations with temperature, the mass concentrations of PM(10) and NO(2), and the air pollution index API (correlation coefficients mid R: R mid R: > or = 0.7, p < or = 0.0001, t test). Mathematical expressions catering to the seasonal variations of atmospheric visibility were thus proposed. By comparison, the proposed visibility prediction models were more accurate than some existing regional models. In addition to improving visibility prediction accuracy, this study would be useful for understanding the context of low atmospheric visibility, exploring possible remedial measures, and evaluating the impact of air pollution and atmospheric visibility impairment in this region.     

Estimation of the global evolution of atmospheric pollution in Salamanca (Spain) during the 1993-2001 period according to one global index (ORAQI)

The aim of this study has been to use a global index to measure the air quality in the city, apart from individual assessment of the values of the concentrations of the different pollutants. We calculated the ORAQI with the data obtained at four air-pollution monitoring stations located in the city of Salamanca over the period between 1993 and 2001. For the calculations, SO2, PM10, NO2, CO and O3 were used as the most significant pollutants for the surroundings of the monitoring stations. The evolution of this index over 9 years is reported, and the repercussion of the most characteristic pollutants of each season of the year on the ORAQI along the whole period analysed is studied. The importance of the summer pollution in the characterisation of the least polluted surroundings was observed. At the most polluted sites, a decrease in the values corresponding to winter occurs, leading the ORAQI to take similar values along the whole year. In general, taking into account the surroundings of all the monitoring stations, the quality of the air to which the inhabitants of the city of Salamanca are exposed to can be said to be good.     

A low cost instrument based on a solid state sensor for balloon-borne atmospheric O(3) profile sounding

The design of an instrument based on a solid state tungsten oxide sensor for making profile measurements of atmospheric ozone from balloon platforms is described. The sensor is operated at a constant temperature, typically 530 [degree]C. The importance of a detailed consideration of the electronic design is demonstrated, with particular reference to the circuit to control the sensor heater. Calibration methods which are straightforward to implement are illustrated, and the results of a test flight alongside an electrochemical ozonesonde are shown. Quantitative agreement within 25% for most of the profile demonstrates the potential of this type of sensor for ozone sounding. Future improvements from manufacture to analysis are expected to improve on this.     

Fluoride pollution of atmospheric precipitation and its relationship with air circulation and weather patterns (Wielkopolski National Park, Poland)

A 2-year study (2010–2011) of fluorides in atmospheric precipitation in the open area and in throughfall in Wielkopolski National Park (west-central Poland) showed their high concentrations, reaching a maximum value of 2 mg/l under the tree crowns. These high values indicate substantial deposition of up to 52 mg/m²/year. In 2011, over 51 % of open area precipitation was characterized by fluoride concentration higher than 0.10 mg/l, and in throughfall such concentrations were found in more than 86 % of events. In 2010, a strong connection was evident between fluoride and acid-forming ions, and in 2011, a correlation between phosphate and nitrite ions was seen. Analysis of available data on F^? concentrations in the air did not show an unequivocal effect on F^? concentrations in precipitation. To find reasons for and source areas of high fluoride pollution, the cases of extreme fluoride concentration in rainwater were related to atmospheric circulation and weather patterns. Weather conditions on days of extreme pollution were determined by movement of weather fronts over western Poland, or by small cyclonic centers with meteorological fronts. Macroscale air advection over the sampling site originated in the western quadrant (NW, W, and SW), particularly in the middle layers of the troposphere (2,500–5,000 m a.s.l.). Such directions indicate western Poland and Germany as possible sources of the pollution. At the same time in the lower troposphere, air inflow was frequently from the north, showing short distance transport from local emitters, and from the agglomeration of Poznań.     

Spatio-temporal analysis of land use/land cover change and its effects on soil erosion (Case study in the Oplenac wine-producing area,Serbia)

In this paper, various spatial modelling techniques were applied to analyse changes in soil cover and their impact on soil erosion in the Oplenac wine-producing area in Serbia in the past (1985 and 2013) and in the future (with predictions for 2041). The Integrated Valuation of Ecosystem Services and Trade-offs Sediment Delivery Ratio (InVEST SDR) model and the Modules for Land Use Change Evaluation (MOLUSCE) model, integrated with methods of remote sensing, were successfully applied and were shown to be valid tools for predicting the impact of Land Use Land Cover (LULC) changes when estimating soil loss. The results revealed that the greatest impact of land use changes between 1985 and 2013 was on a reduction in areas under vineyards and an extension of meadow and pasturelands as an individual and social response to economic conditions during the research period. The forecast for 2041 reflected the trends observed in the previous period, with the greatest changes witnessing an increase in urban areas and a decrease in areas of arable land. It was also found that the effect of LULC changes on spatio-temporal patterns in the Oplenac wine-producing area did not have a major impact on soil loss, meaning this area, with its good agro-climatic characteristics, is suitable for the intensification of agricultural production.     

The effect of light and iron(II)/iron(III) on the distribution of Tl(I)/Tl(III) in fresh water systems

The distribution of aqueous Tl(I)/Tl(III) as a function of light exposure and solution properties was studied by quantifying the oxidation states after separation with ion chromatography and on-line detection with ICP-MS. Ultraviolet irradiation of aqueous solutions containing 1 microg l(-1) Tl(III) and in equilibrium with the atmosphere increases the reduction rate. In systems with photoreduction of Fe(III)(aq) a quantitative oxidation of Tl(I)(aq) was observed, notably at low pH. The process is reversible, as indicated by formation of Tl(I) when the irradiated systems were kept in the dark. In systems with colloidal silica-stabilised ferrihydrite, UV irradiation also leads to oxidation of Tl(I)(aq), but not quantitatively. It is suggested that adsorption of thallium to the ferrihydrite determines the rate of oxidation. Detectable, but not quantitative, oxidation of Tl(I)(aq) took place when natural water samples with 1 microg l(-1) Tl(I)(aq) were exposed to either sunlight or UV-light. For these samples, the reduction was not quantitative when they were kept in the dark for 24 h. The results suggest that the light dependent iron cycle in fresh water systems strongly influences the redox state of thallium.     

Air pollution exposure monitoring and estimating. Part I. Integrated air quality monitoring system

This paper presents an integrated exposure monitoring system, based on an expansion of existing air quality monitoring systems using dispersion modelling. The system allows: (1) identifying geographical areas whose inhabitants are most exposed to ambient pollution; (2) identifying how many people in an area are exposed to concentrations of pollution exceeding air quality guidelines; (3) describing the exposure of population subgroups (e.g. children); (4) planning pollution abatement measures and quantifying their effects; (5) establishing risk assessment and management programs, and (6) investigating the short- and long-term effects of both pollutants and pollution sources on public health. The effect of pollution is rarely very large and in order to discover it, exposure estimation must provide data that reflects both spatial and temporal variations. Estimates of pollution exposure are obtained using an integrated approach that combines results of measurements from monitoring programs with dispersion calculations. These values can serve as estimates for individual short-term or long-term exposure. The grouped data allows the expression of ambient pollution concentrations as the spatial distribution of estimates such as the mean or 98th percentile of such compounds as SO2, O3, NO2, PM10 and PM2.5. This integrated approach has been combined into a single software package, AirQUIS.     

Thermal volatilization properties of atmospheric nanoparticles

Thermal volatilization is explored as a means of inferring the chemical composition of atmospheric aerosol particles with diameters smaller than 10 nm (nanoparticles). Such particles contain too little mass for quantitative chemical determination by traditional analytical methods. Aerosols were subjected to increasing temperature in an oven and particle loss was measured as a function of temperature with the TSI model 3025 ultrafine condensation particle counter (UCPC), which is capable of counting particles with diameters as small as 3 nm. Particle nucleation was observed down stream of the oven when it was heated above about 400°C. To reduce this artifact, the sample air down stream of the oven was cooled to condense the hot gases and/or the freshly nucleated particles before they reached the UCPC. Controlled experiments were done with pure ammonium sulfate (NH₄)₂SO₄ particles. The experimental design was optimized based on the known concentration of pure (NH₄)₂SO₄ particles vaporized in the oven and the diffusion of this material to the walls of the sampling tube before the particle counter.     

Identifying the origin of atmospheric inputs of trace elements in the Prades Mountains (Catalonia) with bryophytes, lichens, and soil monitoring

The biomonitors Hypnum cupressiforme and Xanthoria parietina were used to assess the deposition of trace elements and their possible origin in the Prades Mountains, a protected Mediterranean forest area of NE Spain with several pollution sources nearby. Al, As, Cd, Co, Cu, Cr, Ni, Pb, Sb, Ti, V, and Zn were determined in 16 locations within this protected area. Soil trace element concentrations were also ascertained to calculate enrichment factors (EF) and use them to distinguish airborne from soilborne trace element inputs. In addition, lichen richness was measured to further assess atmospheric pollution. EF demonstrated to be useful not only for the moss but also for the lichen. Cd, Cr, Cu, Ni, and Zn presented values higher than three in both biomonitors. These trace elements were also the main ones emitted by the potential sources of pollutants. The distance between sampling locations and potential pollution sources was correlated with the concentrations of Cu, Sb, and Zn in the moss and with Cr, Ni, and Sb in the lichen. Lichen richness was negatively correlated with lichen Cu, Pb, and V concentrations on dry weight basis. The study reflected the remarkable influence that the pollution sources have on the presence of trace elements and on lichen species community composition in this natural area. The study highlights the value of combining the use of biomonitors, enrichment factors, and lichen diversity for pollution assessment to reach a better overview of both trace elements’ impact and the localization of their sources.     

水磨河氮含量分布及时空变化初探

根据2005年水质监测结果,对水磨河无机氮的特征分布及相互之间的相关性进行了初步分析探讨,结果显示,水磨河无机氮中硝酸盐氮含量最高,亚硝酸盐氮含量最低,亚硝酸盐氮与氨氮之间有非常显著的线性关系.通过对1991-2005年的监测资料分析,表明水磨河各断面无机氮含量呈下降趋势,但水磨河自上而下无机营养盐N总体浓度升高,说明氮污染还在延续,形势不容乐观.     

A Water Quality Monitoring Network Design Methodology for the Selection of Critical Sampling Points: Part I

The principal instrument to temporally and spatially manage water resources is a water quality monitoring network. However, to date in most cases, there is a clear absence of a concise strategy or methodology for designing monitoring networks, especially when deciding upon the placement of sampling stations. Since water quality monitoring networks can be quite costly, it is very important to properly design the monitoring network so that maximum information extraction can be accomplished, which in turn is vital when informing decision-makers. This paper presents the development of a methodology for identifying the critical sampling locations within a watershed. Hence, it embodies the spatial component in the design of a water quality monitoring network by designating the critical stream locations that should ideally be sampled. For illustration purposes, the methodology focuses on a single contaminant, namely total phosphorus, and is applicable to small, upland, predominantly agricultural-forested watersheds. It takes a number of hydrologic, topographic, soils, vegetative, and land use factors into account. In addition, it includes an economic as well as logistical component in order to approximate the number of sampling points required for a given budget and to only consider the logistically accessible stream reaches in the analysis, respectively. The methodology utilizes a geographic information system (GIS), hydrologic simulation model, and fuzzy logic.     

Ambiental dust speciation and metal content variation in TSP, PM10 and PM2.5 in urban atmospheric air of Harare (Zimbabwe)

The effects of timber harvesting on stream water quality and efficiency of alternate streamside management zones were evaluated in Pockwock Lake and Five Mile Lake watersheds in central Nova Scotia, Canada. The streamside management zone (SMZ) included a 20 m no cut, 20 m select cut and a 30 m select cut buffer strips along the stream. Water quality of eight streams, six in harvested and two in not-harvested watersheds were monitored for two years before and two years after the harvesting of timber. Nonparametric statistical tests on stream water quality showed that there was significant change in the concentration of potassium in six streams, manganese in five streams, zinc in two streams and total nitrogen in one stream after timber harvesting. There was no significant change in the quality of water in two streams used as control sites in the neighboring watersheds of similar size and hydrological characteristics. The results show that forest management practices were most favorable in streams maintained with 30 m select cut followed by 20 m no cut and 20 m select cut SMZ. The streamside zone width and treatment of select cut or no cut in the zone played an important role in filtering or retaining the minerals in surface water runoff. In buffer zones of similar width, the buffer zone with no cut or forested buffer was relatively more effective at protecting stream water quality than select cut SMZ. The vegetation in the zone may have decreased the flow velocity and increased residence time and thus increased filtration and retention of minerals in the riparian soil.