The variability of mass concentrations and source apportionment analysis of equivalent black carbon across urban Europe

Black Carbon along a Highway and in a Residential Neighborhood during Rush-Hour Traffic in a Cold Climate

“…The median UB during peak winter is, in turn, arguably lower than the median roadside BC recorded at the stationary HRI site over a three-week period in November (0.6 µg/m 3 , see Section 3.2). As this value compares well to the median BC apportioned to fossil fuel combustion at UB sites in European cities such as Helsinki (Table 4), Birmingham, Zurich and Bern in winter [22], the median winter UB is likely to be lower in Reykjavík than in many other cities in more densely populated regions. Adopting the Urban Background (UB) definition of Boniardi et al [39], which is >50 m and >75 m distance to a minor or major highway (dashed box, Figure 7b), the highest concentrations of ~5 µg/m 3 in the residential neighborhood in this study match the maximum hourly UB values recorded in cities of greater size and more diverse sources of BC (Table 4).…”

“…The median UB during peak winter is, in turn, arguably lower than the median roadside BC recorded at the stationary HRI site over a three-week period in November (0.6 µg/m 3 , see Section 3.2). As this value compares well to the median BC apportioned to fossil fuel combustion at UB sites in European cities such as Helsinki (Table 4), Birmingham, Zurich and Bern in winter [22], the median winter UB is likely to be lower in Reykjavík than in many other cities in more densely populated regions.…”

“…In light of the good average urban air quality in this sparsely populated island nation, the research focused on characterizing the upper range of BC concentrations that the general public could be exposed to during rush-hour traffic in the vicinity and along a central highway in the capital city of Reykjavík. Unlike many studied urban sites in Europe [22], the contribution of residential and commercial wood and coal burning is negligible in winter, as both district heating and electricity are provided by renewable geothermal and hydropower resources. With only 230,000 inhabitants, the city is smaller than most previously studied urban areas.…”

“…Moreover, very stable atmospheric conditions develop during frost stills, trapping pollution near the ground [19][20][21]. However, BC originating from fossil fuel combustion is often masked by increased residential and commercial wood and coal-burning practices in winter [22]. From this perspective, Iceland is an interesting country to study traffic-related BC in a cold climate because the road transport sector is by far the largest contributor to BC, comprising 45% of the national BC emissions [23].…”

Aerosol, Clouds and Trace Gases Research Infrastructure (ACTRIS): The European Research Infrastructure Supporting Atmospheric Science

“…In addition, exceptionally dense smoke layers from megafires in Canada, Australia, Siberia and from Mediterranean forest fires are monitored and reported by ACTRIS, to appropriately model the smoke transport and respective radiation impacts in both the troposphere and the stratosphere (Figure 7). A number of ACTRIS studies related to the COVID-19 pandemic and the series of lockdowns over Europe investigated their impact on air quality both at the European (Putaud et al, 2023), country (Petetin et al, 2020;Putaud et al, 2021) and city scales, e.g. Athens (Eleftheriadis et al, 2021), Paris (Petit et al, 2021), Elche (southeastern Spain) (Clemente et al, 2022), the Po Valley (Cristofanelli et al, 2021), and rural Košetice in the Czech Republic (Mbengue et al, 2023).…”