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In the frame of the EMEP/ACTRIS/COLOSSAL campaign in Milan during winter 2018, equivalent black carbon measurements using the Aethalometer 31 (AE31), the Aethalometer 33 (AE33), and a Multi-Angle Absorption Photometer (MAAP) were carried out together with levoglucosan analyses on 12 h resolved PM2:5 samples collected in parallel. From AE31 and AE33 data, the loading-corrected aerosol attenuation coefficients (bATN) were calculated at seven wavelengths (, where values are 370, 470, 520, 590, 660, 880, and 950 nm). The aerosol absorption coefficient at 637 nm (babsMAAP) was determined by MAAP measurements. Furthermore, babs was also measured at four wavelengths (405, 532, 635, 780 nm) on the 12 h resolved PM2:5 samples by a polar photometer (PPUniMI). After comparing PPUniMI and MAAP results, we exploited PPUniMI data to evaluate the filter multiplescattering enhancement parameter at different wavelengths for AE31 and AE33. We obtained instrument-and wavelength-dependent multiple-scattering enhancement parameters by linear regression of the Aethalometer bATN against the babs measured by PPUniMI. We found significant dependence of the multiple-scattering enhancement parameter on filter material, hence on the instrument, with a difference of up to 30% between the AE31 and the AE33 tapes. The wavelength dependence and day night variations were small-The difference between the smallest and largest value was up to 6 %. Data from the different instruments were used as input to the so-called "Aethalometer model" for optical source apportionment, and instrument dependence of the results was investigated. Inconsistencies among the source apportionment were found fixing the AE31 and AE33 multiple-scattering enhancement parameters to their usual values. In contrast, optimised multiple-scattering enhancement parameters led to a 5% agreement among the approaches. Also, the component apportionment "MWAA model" (Multi-Wavelength Absorption Analyzer model) was applied to the dataset.

The “Carbonaceous Aerosol in Rome and Environs” (CARE) experiment took place at a Mediterranean urban background site in Rome (Italy) deploying a variety of instrumentation to assess aerosol physical-chemical and optical properties with high-time resolution (from 1 min to 2 h). In this study, aerosol optical properties, chemical composition, and size distribution data were examined with a focus on the analysis of several intensive optical properties obtained from multi-wavelength measurements of aerosol scattering and absorption coefficients. The spectral behaviour of several quantities related to both aerosol composition and size was explored, analysing their high-time resolved temporal patterns and combining them in order to extract the maximum information from all the available data. A methodology to separate aerosol types using optical data only is here proposed and applied to an urban area characterised by a complex mixture of particles. A key is given to correctly disentangle cases that could not be distinguished observing only one or few parameters, but that can be clearly separated using a suitable ensemble of optical properties. The SSCAAE, i.e. the wavelength dependence of the Single Scattering co-albedo 1-SSA (where SSA is the Single Scattering Albedo) - that efficiently responds to both aerosol size and chemical composition – resulted to be the best optical intensive parameter to look at for the discrimination between episodes characterised by specific aerosol types (e.g. sea salt, Saharan dust) and more mixed conditions dominated by local emissions. However, this study also highlighted that it is necessary to combine temporal patterns of different optical parameters to robustly associate SSCAAE features to specific aerosol types. In addition, the complete chemical speciation and the high-time resolved size distribution were used to confirm the aerosol types identified via a combination of aerosol optical properties. Look-up tables with most suitable ran

In this study, the performance of two types of source apportionment models was evaluated by assessing the results provided by 40 different groups in the framework of an intercomparison organised by FAIRMODE WG3 (Forum for air quality modelling in Europe, Working Group 3). The evaluation was based on two performance indicators: z-scores and the root mean square error weighted by the reference uncertainty (RMSEu), with pre-established acceptability criteria. By involving models based on completely different and independent input data, such as receptor models (RMs) and chemical transport models (CTMs), the intercomparison provided a unique opportunity for their cross-validation. In addition, comparing the CTM chemical profiles with those measured directly at the source contributed to corroborate the consistency of the tested model results. The most commonly used RM was the US EPA- PMF version 5. RMs showed very good performance for the overall dataset (91% of z-scores accepted) while more difficulties were observed with the source contribution time series (72% of RMSEu accepted). Industrial activities proved to be the most difficult sources to be quantified by RMs, with high variability in the estimated contributions. In the CTMs, the sum of computed source contributions was lower than the measured gravimetric PM10 mass concentrations. The performance tests pointed out the differences between the two CTM approaches used for source apportionment in this study: brute force (or emission reduction impact) and tagged species methods. The sources meeting the z-score and RMSEu acceptability criteria tests were 50% and 86%, respectively. The CTM source contributions to PM10 were in the majority of cases lower than the RM averages for the corresponding source. The CTMs and RMs source contributions for the overall dataset were more comparable (83% of the z-scores accepted) than their time series (successful RMSEu in the range 25% - 34%). The comparability between CTMs and RMs va

Significant data from thermal comfort studies conducted in indoor built environment have been included in databases worldwide, e.g. the ASHRAE Global Thermal Comfort Database II, where Brazil holds a relevant position. The records include a total of 10,925 thermal comfort votes, coming from field studies mainly conducted in offices and schools. Thus, this paper aims to present the database, describing its characteristics and main results from a preliminary analysis. The method was based on the standardization and treatment of raw data from field studies, and some analysis of thermal perception responses and environmental variables were performed. The results highlighted some important variations in thermal perception among people from different climates in Brazilian territory, which is also influenced by the current ventilation system mode. People from Brazilian tropical climates showed a neutral thermal sensation balance close to 27.4 °C of mean operative temperature; meanwhile, those from subtropical climates were close to 24.4 °C. The overall thermal preference tended to cooler than neutral, particularly in naturally ventilated environments. The contributions of this investigation are mainly related to the gaps identified in the database, such as limited climate types and building typologies. Thus, the database expansion would provide valuable information to be analysed and further incorporated in the Brazilian Standard.

The Aethalometer (AE; Magee Scientific) is a widely used filter-based instrument that provides in-situ realtime optical measurements of light absorbing aerosols in 7 different wavelengths ranging from 370nm to 950nm. As for any other filter-based technique, Aethalometer measurements are affected by two artefacts: the multiple-scattering effects caused by the scattering of sampling light by both the filter fibres and the aerosol particles on the filter (C(l) in Eq. 1) and the loading effect due to the saturation of the measurement as a function of deposited particles (RATN(l) in Eq. 1).

Fish bones are still an unknown tool in taphonomic studies. We have carried out several experiments which have shown that fish bones may provide key taphonomic traits. Fossil fish bones in archaeological sites (from caves to riverbanks or seashores) are frequently result of predation by humans or any other predator, as well as abiotic agents. The original environment of fish is aquatic restricted to specific water contexts and the presence of fish in fossil sites provides relevant information regarding paleoenvironments, human/animal predatory behaviors, and site formation. In spite of the interest of fossil fish remains, most taphonomic experiments have been focused on mammalian fossil bones. This paper shows results obtained from experiments that help interpreting palaeoenvironmental changes, potential space-time mixtures, and site formation. Our experiments have provided distinct criteria to distinguish the action of sand projected by wind, friction of bones against sand substrates, or sand with or without water abrading the bone surface. Experimental results have been compared to an archaeological case: El Americano II site (middle Holocene, Argentina) to elucidate how the site was formed. Criteria obtained so far from each type of experiment described here greatly increase knowledge for interpreting other sites that yield fossil fish bones.