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Light-absorbing carbonaceous aerosols (including black carbon (BC)) pose serious health issues and play significant roles in atmospheric radiative properties. Two-year measurements (2015–2016) of aerosol light absorption, combined with measurements of sub-micrometric particles, were continuously conducted in A Coruña (northwest (NW) Spain) to determine their light absorption properties: absorption coefficients (σabs) and the absorption Ångström exponent (AAE). The mean and standard deviation of equivalent black carbon (eBC) during the period of study were 0.85 ± 0.83 µg m−3, which are lower than other values measured in urban areas of Spain and Europe. High eBC concentrations found in winter are associated with an increase in emissions from anthropogenic sources in combination with lower mixing layer heights and frequent stagnant conditions. The pronounced diurnal variability suggests a strong influence from local sources. AAE had an average value of 1.26 ± 0.22 which implies that both fossil fuel combustion and biomass burning influenced optical aerosol properties. This also highlights biomass combustion in suburban areas, where the use of wood for domestic heating is encouraged, as an important source of eBC. All data treatment was gathered using SCALA© as atmospheric aerosol data management support software program. [ABSTRACT FROM AUTHOR]

Currently, gas chromatography is the most common analytical technique for natural gas (NG) analysis as it offers very precise results, with very low limits of detection and quantification. However, it has several drawbacks, such as low turnaround times and high cost per analysis, as well as difficulties for on-line implementation. With NG applications rising, mostly thanks to its reduced gaseous emissions in comparison with other fossil fuels, the necessity for more versatile, fast, and economic analytical methods has augmented. This work summarizes the latest advances to determine the composition and physico-chemical properties of regasified liquid natural gas, focusing on infrared spectroscopy-based techniques, as well as on data processing (chemometric techniques), necessary to obtain adequate predictions of NG properties. [ABSTRACT FROM AUTHOR]

Due to the exponential growth of the SARS-CoV-2 pandemic in Spain (2020), the Spanish Government adopted lockdown measures as mitigating strategies to reduce the spread of the pandemic from 14 March. In this paper, we report the results of the change in air quality at two Atlantic Coastal European cities (Northwest Spain) during five lockdown weeks. The temporal evolution of gaseous (nitrogen oxides, comprising NOx, NO, and NO2; sulfur dioxide, SO2; carbon monoxide, CO; and ozone, O3) and particulate matter (PM10; PM2.5; and equivalent black carbon, eBC) pollutants were recorded before (7 February to 13 March 2020) and during the first five lockdown weeks (14 March to 20 April 2020) at seven air quality monitoring stations (urban background, traffic, and industrial) in the cities of A Coruña and Vigo. The influences of the backward trajectories and meteorological parameters on air pollutant concentrations were considered during the studied period. The temporal trends indicate that the concentrations of almost all species steadily decreased during the lockdown period with statistical significance, with respect to the pre-lockdown period. In this context, great reductions were observed for pollutants related mainly to fossil fuel combustion, road traffic, and shipping emissions (−38 to −78% for NO, −22 to −69% for NO2, −26 to −75% for NOx, −3 to −77% for SO2, −21% for CO, −25 to −49% for PM10, −10 to −38% for PM2.5, and −29 to −51% for eBC). Conversely, O3 concentrations increased from +5 to +16%. Finally, pollutant concentration data for 14 March to 20 April of 2020 were compared with those of the previous two years. The results show that the overall air pollutants levels were higher during 2018–2019 than during the lockdown period. [ABSTRACT FROM AUTHOR]

Atmospheric particle-bound mercury (PHg) quantification, at a pg m−3 level, has been assessed in particulate matter samples (PM10) at several sites (industrial, urban and sub-urban sites) of Atlantic coastal European region during 13 months by using a direct thermo-desorption method. Analytical method validation was assessed using 1648a and ERM CZ120 reference materials. The limits of detection and quantification were 0.25 pg m−3 and 0.43 pg m−3, respectively. Repeatability of the method was generally below 12.6%. PHg concentrations varied between 1.5–30.8, 1.5–75.3 and 2.27–33.7 pg m−3 at urban, sub-urban and industrial sites, respectively. PHg concentration varied from 7.2 pg m−3 (urban site) to 16.3 pg m−3 (suburban site) during winter season, while PHg concentrations varied from 9.9 pg m−3 (urban site) to 19.3 pg m−3 (suburban site) during the summer. Other trace elements, major ions, black carbon (BC) and UV-absorbing particulate matter (UV PM) was also assessed at several sites. Average concentrations for trace metals (Al, As, Bi, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Si, Sr, V and Zn) ranged from 0.08 ng m−3 (Bi) at suburban site to 1.11 µg m−3 (Fe) at industrial site. Average concentrations for major ions (including Na+, K+, Ca2+, NH4+, Mg2+, Cl−, NO3− and SO42−) ranged from 200 ng m−3 (K+) to 5332 ng m−3 (SO42−) at urban site, 166 ng m−3 (Mg2+) to 4425 ng m−3 (SO42−) at suburban site and 592 ng m−3 (K+) to 5853 ng m−3 (Cl−) at industrial site. Results of univariate analysis and principal component analysis (PCA) suggested crustal, marine and anthropogenic sources of PHg in PM10 at several sites studied. Toxicity prediction of PHg, by using hazard quotient, suggested no non-carcinogenic risk for adults. [ABSTRACT FROM AUTHOR]

SCALA© (Sampling Campaigns for Aerosols in the Low Atmosphere) is a web-based software system that was developed in a multidisciplinary manner to integrally support the documentation and the management and analysis of atmospheric aerosol data from sampling campaigns. The software development process applied considered the prototyping and the evolutionary approaches. The software product (SCALA©) allows for the comprehensive management of the sampling campaigns' life cycle (management of the profiles and processes involved in the start-up, development and closure of a campaign) and provides support for both intra- and inter-campaigns data analysis. The pilot deployment of SCALA© considers the Spanish Network on Environmental Differential Mobility Analysers (DMAs) (REDMAAS) and the PROACLIM project. This research project involves, among other objectives, the study of temporal and spatial variations of the atmospheric aerosol through a set of microphysical properties (size distribution, optical properties, hygroscopicity, etc.) measured in several locations in Spain. The main conclusions regarding size distribution are presented in this work. These have been have been extracted through SCALA© from the data collected in the REDMAAS 2015 and 2019 intercomparison campaigns and two years (2015 and 2016) of measurements with two Scanning Mobility Particle Sizers (SMPS) at CIEMAT (Madrid, central Spain) and UDC (A Coruña, NW of Spain) sites. [ABSTRACT FROM AUTHOR]