Source-dependent absorption Ångström exponent in the Los Angeles Basin: Multi-time resolution factor analyses of ambient PM and aerosol optical absorption.

Advanced receptor models can leverage the information derived from optical and chemical variables as input by a variety of instruments at different time resolutions to extract the source specific absorption Ångström exponent (AAE) from aerosol absorption. The multilinear engine (ME-2), a Positive Matrix Factorization (PMF) solver, serves as a proficient tool for performing such analyses, thereby overcoming the constraints imposed by the assumptions in current optical source apportionment methods such as the Aethalometer approach since the use of a-priori AAE values introduces additional uncertainty into the results of optical methods. Comprehensive PM chemical speciation datasets, and aerosol absorption coefficients (b, λ) at seven wavelengths measured by an Aethalometer (AE33), were used in multi-time source apportionment (MT-PMF).

A European aerosol phenomenology - 9: Light absorption properties of carbonaceous aerosol particles across surface Europe.

Carbonaceous aerosols (CA), composed of black carbon (BC) and organic matter (OM), significantly impact the climate. Light absorption properties of CA, particularly of BC and brown carbon (BrC), are crucial due to their contribution to global and regional warming. We present the absorption properties of BC (b) and BrC (b) inferred using Aethalometer data from 44 European sites covering different environments (traffic (TR), urban (UB), suburban (SUB), regional background (RB) and mountain (M)).

Arsenic distribution and speciation in deposited coal mine dust.

This study investigates arsenic (As) species, sources, and transformation patterns in deposited coal mine dust (DCMD) from three coal mines-QSY, MHJ, and SCC-in the Ningdong Coalfield, China. While the parent coals have low As levels, the DCMD shows significant enrichment, with concentrations 137 to 345 times higher. The mineral composition of the DCMD reflects that of the parent coals but includes secondary minerals such as gypsum and various trace elements, including As.

Source apportionment of ultrafine particles in urban Europe.

There is a body of evidence that ultrafine particles (UFP, those with diameters ≤ 100 nm) might have significant impacts on health. Accordingly, identifying sources of UFP is essential to develop abatement policies. This study focuses on urban Europe, and aims at identifying sources and quantifying their contributions to particle number size distribution (PNSD) using receptor modelling (Positive Matrix Factorization, PMF), and evaluating long-term trends of these source contributions using the non-parametric Theil-Sen's method.

Size distribution, sources and chemistry of ultrafine particles at Barcelona-El Prat Airport, Spain.

The rapid expansion of the aviation sector raises concerns about air quality impacts within and around airports. Ultrafine particles (UFP, diameter < 100 nm) are of particular concern due to their potential adverse health effects. In this study, particle number concentrations (PNC), particle number size distribution (PNSD), and other ancillary pollutants such as particulate matter (PM), nitrogen oxides (NO), black carbon (BC), sulfur dioxide (SO), ozone (O), carbon monoxide (CO) and benzene, as well as organic markers and trace elements (in quasi-UFP) were measured at Barcelona-El Prat Airport (80 m and 250 m from the main taxiway and runway).