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Abstract: This paper analyzes the mass size distribution of some inorganic species present in the atmospheric aerosol from a field campaign carried out in Madrid throughout a complete year (February 2007–February 2008). Samplings were performed by means of a micro-orifice uniform deposit impactor (MOUDI). Ambient air was sampled during consecutive nocturnal and diurnal periods, and diurnal/nocturnal behaviors were compared for the twenty night-day sampling pairs that were gathered. Annual and seasonal averages were obtained, and some case studies under specific atmospheric conditions are discussed in the paper. Results have shown that the sulfate and ammonium mass was concentrated in the accumulation mode, between 0.18 and 0.56μm, so that gas-phase and condensation processes for secondary aerosol formation prevailed during the sampling periods in this area. An exception to this behavior was found during a fog event when distributions for these two species were centered in the 0.56–1 and 1–1.8μm size stages, corresponding to the droplet mode. In most of the samples, the ammonium mass measured in these size ranges was enough or almost enough to neutralize inorganic acidity by formation of ammonium sulfate and nitrate. However, a significant sulfate mass not neutralized by ammonium was found in the impactor backup quartz filter (aerodynamic diameter<0.056μm). The concentration of this sulfate and its contribution to the ultrafine fraction mass was higher under good dispersive conditions, prevailing in summer, when particle growth processes are not so favored due to the higher atmospheric dilution factors. The origin of this ultrafine sulfate has been attributed to direct emissions from traffic, associated to the nucleation mode. Regarding the nitrate concentration, it was found higher in the coarse mode than in the accumulation mode on an annual basis. The highest concentrations were measured in winter episodic situations. The marked seasonal variability shown in the accumulation mode by this species is related to the volatility of ammonium nitrate. Among all the studied ions, nitrate also presented the highest differences between the diurnal and nocturnal concentrations in all size ranges. This is probably related to the short time scale required for its formation from gaseous precursors. [Copyright &y& Elsevier]

This paper assesses the temporal variations of surface ozone concentrations during the period 2001–2010 in 3 regions of Spain with different geographical and socioeconomic features (northern coastland, central inland and northeast inland), as well as its link with atmospheric circulation. Specifically, daily surface atmospheric patterns over the aforementioned regions are characterized using NCEP/NCAR reanalysis data and an objective classification scheme in order to study the relationship between synoptic weather types and daily ozone levels. The results show that tropospheric ozone concentration has a tendency towards an increase during the study period, both during daytime and nighttime. Moreover, in general, this upward trend is seen throughout all of the seasons. The observed trends are in line with a reported decrease of NO X emissions and increase in surface solar radiation during the 2000s in Spain. On the other hand, interestingly, median concentrations were statistically significantly lower in days with anticyclonic weather conditions than in the rest of meteorological situations, while days with a directional weather type showed higher median levels of ozone concentration, with maximum values in days with northern and eastern component. Due to the detrimental effect that ozone has on human health, the relationship between synoptic weather patterns and daily ozone levels shown in this work could potentially be used for implementing pollution level alert protocols depending on forecast weather types. [ABSTRACT FROM AUTHOR]

Abstract: The experimental campaign “Determination of the sources of atmospheric Aerosols in Urban and Rural Environments in Spain” (DAURE) took place in a urban (Barcelona city) and a rural (the Montseny Natural Park) Spanish sites. Its main objective was to study the formation and transport processes of particulate matter in the region during winter and summer time. This paper presents a description of the meteorological conditions during the campaign by means of meteorological observations, high-resolution mesoscale meteorological modelling and backward Lagrangian particle dispersion simulations. Modelling results are in agreement with observations and provide a valuable tool for characterizing transport patterns in relation to episodes of air pollution. An objective classification of the synoptic conditions and a classification of the main local dispersion patterns is presented and discussed. Additionally, the measured PM1 and PM10 levels in both urban and rural sites are discussed and related to the meteorological conditions observed. [Copyright &y& Elsevier]

Abstract: This paper focuses on 7Be concentration in the atmospheric surface aerosols of the Spanish city of Granada, in the southern Iberian Peninsula. We analyze the effects of meteorological conditions in the geographical zone over the period 2005–2009. A prediction model is suggested to describe the behaviour of atmospheric aerosols containing 7Be. The model was applied from January to May 2010 and shows that temperature, relative humidity and precipitation are the meteorological factors responsible for the behaviour of atmospheric aerosols. The statistical significance of the results was 99%. This study helps understanding of the atmosphere of Granada as well as the climate variables responsible for transportation and deposition of atmospheric aerosols. Moreover, in case of a massive release of radionuclides into the atmosphere, the results of this study will help predict behaviour in this city and other continental areas with a similar climate. [Copyright &y& Elsevier]

Abstract: The CALIOPE high-resolution air quality modeling system (4 km × 4 km, 1 h) estimates particulate matter from two aerosol models, CMAQv4.5 (AERO4) and BSC-DREAM8b. While CMAQv4.5 calculates biogenic, anthropogenic and sea-salt aerosols; BSC-DREAM8b provides hourly estimates of the natural mineral dust contribution from North Africa deserts. This paper presents an evaluation of the CALIOPE system to reproduce the spatial and temporal variability levels of PM2.5, PM10 and chemical composition (nitrate, non-marine sulfate, ammonium, organic and elemental carbon, sea-salt, and desert dust) across Spain. The evaluation is performed against ground-based observations for the year 2004, when a number of time series of chemically speciated compounds were available. A new data set of Saharan dust PM10 concentration is used to evaluate the PM10 contribution modeled by BSC-DREAM8b. The results indicate that both natural aerosol sea-salt and desert dust accomplish the model performance criteria (MFE ≤ 75% and MFB ± 60%). Modeled PM10 sea-salt is highly dependent on wind speed and presents high correlation with experimental data in coastal areas (r = 0.67). The BSC-DREAM8b is able to reproduce the daily variability of the observed levels of desert dust and most of the outbreaks affecting southern Spain. Species in the equilibrium (e.g. sulfate/nitrate/ammonium) are highly correlated each other and show high dependency on ammonia emissions. Non-marine sulfate and ammonium are underestimated by a factor of 3. An underestimation of nitrate was also seen (factor of 2). Fine carbonaceous aerosols present the highest underestimations (factor of 4) in part related to the state-of-the-science concerning secondary organic aerosol formation pathways. Spatial and seasonal variability of PM2.5, PM10 and their chemical compounds increase the correlation with observations when multiplicative bias-correction factors for the aforementioned underestimated species are taking into account. Furthermore, simulated spatial and seasonal patterns of aerosol agree with those described in related studies based on experimental values. [ABSTRACT FROM AUTHOR]

Abstract: This paper quantifies the very short-term variability of the total solar irradiance and the ultraviolet erythemal irradiance (UVER) averaged over 1-min intervals at Granada (Southeastern Spain). A statistical analysis for a four-year period (January 2006–December 2009) under different cloudiness and characterized by the amount of cloud cover (oktas) retrieved from an All-Sky Imager located next to the radiometers is presented. Very short-term variability of the total solar irradiance was larger than UVER fluctuations under cloudy conditions (above three oktas), in accordance with previous works found in the literature. Nevertheless, for cloud cover bellow three oktas the opposite was true; the median relative 1-min fluctuation was larger for UVER than for total solar irradiance. Moreover, while the coefficient of variation (CV) for UVER presented a clear dependence on the solar zenith angle (SZA) under completely cloud-free conditions (from 1.5% for SZA = 20° to 9.5% for SZA = 65°), the CV of the total solar irradiance was under 1.3% with a more stable behaviour for the entire range of SZA. Large differences were found for cloud cover of seven oktas, where the median diurnal 1-min variability for total solar irradiance was 3.9% min−1 compared to 2.5% min−1 for UVER data. Additionally, an episode with surface total solar irradiance higher than its corresponding extraterrestrial value is analyzed. [Copyright &y& Elsevier]

Abstract: Damage caused to objects of cultural heritage is one of the most serious detrimental effects of air pollutants. Within the 6th Framework Programme of the EU, the CULT-STRAT project is an inter-agency, multi-disciplinary project that has integrated research and monitoring information to provide answers to policy and management questions, which relate the effects of air pollutants on heritage and the management options available to mitigate them. The overall aim of the project has been to assess and predict the effects of different pollutants on materials and objects of cultural heritage in a multipollutant scenario and to identify indicators and thresholds levels of pollutants. These have been used for development of management strategies for sustainable maintenance and preventive conservation of European Cultural Heritage and air quality policy from continental to local scale. The present paper reports one of the studies carried out in the CULT-STRAT project at city level and focused on the town of Madrid (Spain). Different maps are shown for the present and possible future scenarios (2010 and 2020): inventory of stock of cultural heritage for each selected material, concentration of selected pollutants (SO2, NO2, O3 and PM10), corrosion (cast bronze) and recession (Portland limestone), exceedance of tolerable degradation thresholds for each material and corrosion-cultural heritage overlapped maps. [Copyright &y& Elsevier]

Abstract: In recent years, research on ozone variability has mainly focused on the analysis of its trend. Additionally some studies have analyzed the annual, seasonal and day-to-day ozone variations. However, intra-diurnal total ozone variations are notably less explored. Thus, the main objective of this paper is to analyze the diurnal variability of total ozone column (TOC) as recorded by a Brewer spectrophotometer in Madrid (Spain). The results show that about 90% of days present non-negligible diurnal variability, indicating that, in general, it should not be assumed that TOC remains constant throughout a particular day in urban areas. In addition, this variability has a notable seasonal behavior which should be considered (the spring and summer months show higher diurnal TOC variations than autumn and winter months). This pattern is likely caused by the diurnal photochemical processes in the lower troposphere related to the formation of tropospheric ozone near the earth’s surface at populated urban locations. Thus, these diurnal fluctuations in tropospheric ozone could explain part of diurnal TOC variations (between 20% and 70% depending on the mixing layer height). [Copyright &y& Elsevier]

Abstract: In Bilbao (Spain), an air quality network measures sulphur dioxide levels at 4 locations. The objective of this paper is to develop a practical methodology to identify redundant sensors and evaluate a network''s capability to correctly follow and represent SO2 fields in Bilbao, in the frame of a continuous network optimization process. The methodology is developed and tested at this particular location, but it is general enough to be useable at other places as well, since it is not tied neither to the particular geographical characteristics of the place nor to the phenomenology of the air quality over the area. To assess the spatial variability of SO2 measured at 4 locations in the area, three different techniques have been used: Self-Organizing Maps (SOMs), cluster analysis (CA) and Principal Component Analysis (PCA). The results show that the three techniques yield the same results, but the information obtained via PCA can be helpful not only for that purpose but also to throw light on the major mechanisms involved. This might be used in future network optimization stages. The main advantage of cluster analysis and SOMs is that they provide readily interpretable results. All the calculations have been carried out using the freely available software R. [Copyright &y& Elsevier]

Global warming and air quality are headline environmental issues of our time and policy must preempt negative international effects with forward-looking strategies. As part of the revision of the European National Emission Ceilings Directive, atmospheric emission projections for European Union countries are being calculated. These projections are useful to drive European air quality analyses and to support wide-scale decision-making. However, when evaluating specific policies and measures at sectoral level, a more detailed approach is needed. This paper presents an original methodology to evaluate emission projections. Emission projections are calculated for each emitting activity that has emissions under three scenarios: without measures (business as usual), with measures (baseline) and with additional measures (target). The methodology developed allows the estimation of highly disaggregated multi-pollutant, consistent emissions for a whole country or region. In order to assure consistency with past emissions included in atmospheric emission inventories and coherence among the individual activities, the consistent emission projection (CEP) model incorporates harmonization and integration criteria as well as quality assurance/quality check (QA/QC) procedures. This study includes a sensitivity analysis as a first approach to uncertainty evaluation. The aim of the model presented in this contribution is to support decision-making process through the assessment of future emission scenarios taking into account the effect of different detailed technical and non-technical measures and it may also constitute the basis for air quality modelling. The system is designed to produce the information and formats related to international reporting requirements and it allows performing a comparison of national results with lower resolution models such as RAINS/GAINS. The methodology has been successfully applied and tested to evaluate Spanish emission projections up to 2020 for 26 pollutants but the methodology could be adopted for any particular region for different purposes, especially for European countries. [Copyright &y& Elsevier]

A detailed analysis of the columnar optical aerosol properties has been carried out for data collected during the “El Arenosillo 2004 summer campaign”. These data are derived from a Cimel sun-photometer, as part of the PHOTONS-AERONET network at the El Arenosillo site in south-western Spain, over the period 1 June to 31 October 2004. Version 1 AERONET inversion products are used in the analysis. The aim of this campaign was to obtain a more complete set of data on aerosol particle microphysical, optical/radiative, absorbing and chemical properties for use in closure studies. In this paper we focus on the characterization of the aerosol optical depth (AOD)–alpha coefficients, and the particle size distribution together with their associated microphysical parameters, such as volume concentration, effective radius, etc., in order to define the features and ranges of these physical parameters associated with both fine and coarse particle modes. The requirement of high AOD values for using the inversion technique puts significant constraints on the estimation of the single scattering albedo (SSA) and refractive index, and thus requires great care in the analysis. As a result, only the characterizations of these parameters for desert dust events are considered reliable. Moreover, summer 2004 had the most frequent desert dust intrusions, including the most intense event (22–28 July and 31 July–2 August) ever recorded at the El Arenosillo site since the start of the measurements in February 2000. We summarize the results for the intensive summer campaign in terms of the range of values of the physical and optical parameters of the different aerosol types present in this area of Spain. [Copyright &y& Elsevier]

The objective of this paper is to show the methodology developed to estimate particle emissions from several typical activities of bulk handling in harbours. It is based on several field experiments carried out in the Harbour of Tarragona, where high time resolution monitors were deployed close to different areas of bulk solids handling operations. Monitors recorded particle concentrations and meteorological variables. A high-resolution dispersion model is used to estimate the emission rates that best fits the observations. Results were comparable to those obtained with the AP-42 (EPA). The new emission estimates are used as input for an emission model called EMIPORT. The model also employs AP-42 (EPA) emission factors as a complement. This work is one of the activities of the LIFE project called HADA (Herramienta Automática de Diagnóstico Ambiental or in English Automatic Tool for Environmental Diagnostic). [Copyright &y& Elsevier]

This paper describes the results of a study of pollutant emissions by road traffic in Spain during the period 1988–1999. The study has covered two main phases: input data compilation and program execution (COPERT III).The first has been conditioned by the requirements imposed by the software in terms of de-aggregated data, which were not available at first, and required estimation. Adequate models and algorithms were developed, establishing different hypotheses based on statistical criteria and on current literature. They provided the input data for COPERT III and constitute a result in themselves, offering reliable estimations on number of vehicles and other aspects.The final result of the study has been the estimates of the evolution of pollutant emissions during the period of study. A series for each particular pollutant has been obtained.Based on these results, the effects of the different regulations introduced and of the increase of mobility during the period can be observed qualitatively and quantitatively. Vehicle renewal, more strict regulation of fuel composition and of vehicle emissions have significantly reduced local, sulphur and lead-compound emissions, while mainly due to the increase in mobility, a sustained growth in global emissions has taken place. [Copyright &y& Elsevier]

The results of a field study carried out in September-October 2000 near Madrid, regarding Quercus ilex and Pinus pinea monoterpene emission and its relation to ambient and physiological parameters, are presented in this paper. The major compounds in diurnal Q. ilex emission were limonene, α-pinene and β-pinene. Emission rates during warm days fitted reasonably well to the temperature and light-dependent model of Guenther (E[sub S] = 13.4 µg g[sup -1, DW] h[sup -1]). However, during hot days at mid-day and afternoon hours, dramatic decreases of monoterpene emission, photosynthetic activity and stomatal conductance were observed. The poor soil-water availability combined with low relative humidity and high temperature is likely to be responsible for the observed emission drop. A parameterisation of emission, based on ambient atmospheric water vapour pressure deficit (WVPD), has been attempted in this study. Monoterpene diurnal emission from P. pinea was lower than that of Mediterranean oak (E[sub S] = 1.5 µg g[sup -1, sub DW]h[sup -1]). A reduction in the total emission during the hottest hours of the day was not observed in this monoterpene storing species. Limonene emission rates, accounting on average for nearly half of the emission, were well described by the temperature-dependent model of Tingey. The rest of the emission was comprised of several compounds (cineole, myrcene, α-pinene, linalool) and was reduced at high WVPD values. [ABSTRACT FROM AUTHOR]

Direct normal irradiance is the component of solar radiation exploited by concentrating solar power plants. However, solar radiation reflected by heliostats can be partially extinguished on its way to the receivers in solar power tower plants. These energy losses are accentuated with the distance travelled by the light. The growing development of solar power tower plants has highlighted the interest in determining this phenomenon. This paper presents the results of a six-month intercomparison campaign of the two most promising extinction measuring systems. The system developed at Plataforma Solar de Almería (SE Spain) is based on a direct measurement methodology by using two digital cameras. The second system indirectly estimates the extinction from forward-scatter meter (FSM) measurements. Two FSMs were used in this study. Both FSMs provided the same Meteorological Optical Range (MOR) trends, with differences into declared error margins. A selected number of days corresponding to medium to high aerosol loads have been used to assess the performance of both types of systems. Results show that, in these days, the atmospheric extinction coefficient values derived from the two-camera system were on average 2.1 times higher than those determined with the FSMs. Semi-empirical and empirical corrections for the aerosol spectral characteristics and for the content of water vapour in the atmosphere have been applied to the FSM measurements so that both systems provide similar values of horizontal attenuation. • Solar radiation horizontal attenuation values from two different systems during a 6-month campaign have been compared. • One system is based on two identical digital cameras and other on forward-scatter meters (FSM). • Discrepancies between both systems have been found that largely depend on the type of aerosol. • An algorithm has been described to correct the FSM measurements for aerosols and water vapour on the surface. [ABSTRACT FROM AUTHOR]