Regions of open water and melting sea ice drive new particle formation in North East Greenland

10 pages, 5 figures, supporting information https://dx.doi.org/10.1038/s41598-018-24426-8Atmospheric new particle formation (NPF) and growth significantly influences the indirect aerosol-cloud effect within the polar climate system. In this work, the aerosol population is categorised via cluster analysis of aerosol number size distributions (9-915 nm, 65 bins) taken at Villum Research Station, Station Nord (VRS) in North Greenland during a 7 year record (2010-2016). Data are clustered at daily averaged resolution; in total, we classified six categories, five of which clearly describe the ultrafine aerosol population, one of which is linked to nucleation events (up to 39% during summer). Air mass trajectory analyses tie these frequent nucleation events to biogenic precursors released by open water and melting sea ice regions. NPF events in the studied regions seem not to be related to bird colonies from coastal zones. Our results show a negative correlation (r =-0.89) between NPF events and sea ice extent, suggesting the impact of ultrafine Arctic aerosols is likely to increase in the future, given the likely increased sea ice melting. Understanding the composition and the sources of Arctic aerosols requires further integrated studies with joint multi-component ocean-atmosphere observation and modellingThe study was supported by the Spanish Ministry of Economy through projects BIO-NUC (CGL2013-49020-R) and RyC (RYC-2012-11922), and by the EU though the FP7-PEOPLE-2013-IOF programme (Project number 624680, MANU – Marine Aerosol NUcleations). The National Centre for Atmospheric Science NCAS Birmingham group is funded by the UK Natural Environment Research Council. [...] This work was financially supported by the Danish Environmental Protection Agency with means from the MIKA/DANCEA funds for Environmental Support to the Arctic Region, which is part of the Danish contribution to “Arctic Monitoring and Assessment Program” (AMAP) and to the Danish research project “Short lived Climate Forcers” (SLCF), and the Danish Council for Independent Research (project NUMEN, DFF-FTP-4005-00485B). [...] This work was also supported by the Nordic Centre of Excellence (NCoE) Cryosphere-Atmosphere Interactions in a Changing Arctic Climate (CRAICC). The Villum Foundation is acknowledged for funding the construction of Villum Research Station, Station NordPeer Reviewe

Physicochemical Characterization of Iberian Wildfire Aerosol at Multiple European Sites

A major wildfire event on the Iberian Peninsula resulted in smoke plumes transported across Europe in October 2017. We report aerosol chemical speciation monitor (ACSM) data on fine particle composition and auxiliary measurements from Spain, France, Denmark and Sweden. Our aim is to elucidate the physicochemical properties of ageing biomass burning particles and contribute to estimates of impact on air quality of severe wildfire episodes..

Elucidating the present-day chemical composition, seasonality and source regions of climate-relevant aerosols across the Arctic land surface.

The Arctic is warming two to three times faster than the global average, and the role of aerosols is not well constrained. Aerosol number concentrations can be very low in remote environments, rendering local cloud radiative properties highly sensitive to available aerosol. The composition and sources of the climate-relevant aerosols, affecting Arctic cloud formation and altering their microphysics, remain largely elusive due to a lack of harmonized concurrent multi-component, multi-site, and multi-season observations. Here, we present a dataset on the overall chemical composition and seasonal variability of the Arctic total particulate matter (with a size cut at 10 mu m, PM10, or without any size cut) at eight observatories representing all Arctic sectors. Our holistic observational approach includes the Russian Arctic, a significant emission source area with less dedicated aerosol monitoring, and extends beyond the more traditionally studied summer period and black carbon/sulfate or fine-mode pollutants. The major airborne Arctic PM components in terms of dry mass are sea salt, secondary (non-sea-salt, nss) sulfate, and organic aerosol (OA), with minor contributions from elemental carbon (EC) and ammonium. We observe substantial spatiotemporal variability in component ratios, such as EC/OA, ammonium/nss-sulfate and OA/nss-sulfate, and fractional contributions to PM. When combined with component-specific back-trajectory analysis to identify marine or terrestrial origins, as well as the companion study by Moschos et al 2022 Nat. Geosci. focusing on OA, the composition analysis provides policy-guiding observational insights into sector-based differences in natural and anthropogenic Arctic aerosol sources. In this regard, we first reveal major source regions of inner-Arctic sea salt, biogenic sulfate, and natural organics, and highlight an underappreciated wintertime source of primary carbonaceous aerosols (EC and OA) in West Siberia, potentially associated with the oil and gas sector. The presented dataset can assist in reducing uncertainties in modelling pan-Arctic aerosol-climate interactions, as the major contributors to yearly aerosol mass can be constrained. These models can then be used to predict the future evolution of individual inner-Arctic atmospheric PM components in light of current and emerging pollution mitigation measures and improved region-specific emission inventories

European intercomparison for receptor models : preliminary results

Receptor models are commonly used to identify the sources of ambient particulate matter (PM) in Europe. However, the use of different tools and methodological approaches make it difficult to compare the results of different studies. In order to promote harmonization in this field an intercomparison exercise involving 16 expert groups was organized and evaluated by the JRC within the framework of FAIRMODE. The test DB consisted of 178 PM2.5 speciated samples deriving from two real-world re-arranged DBs (Lee & Hopke, 2006 JGR; Jaeckels et al., 2007 EST). Concentrations and uncertainties of 46 inorganic and organic species were used to characterize the PM. A total of 22 solutions obtained using the following models or model versions were reported for evaluation: EPA-PMF3 (8), PMF2 (6), EPA-CMB 8.2 (4), PCA (1), APCS (1), COPREM (1) and ME-2 (1). Although data in the DB were partially pre-processed, participants had to scrutinize the DB in order to identify, solve and report typical imperfections of real world DBs (e.g. missing values, values below detection limits, outliers and unusual uncertainty patterns). Participants reported the number and label of the identified sources, their contribution estimation (SCE) and uncertainty. In addition, the source/factor chemical profiles and the contribution of each source/factor in each sample were also requested. The match between observed and modelled PM mass in every sample was assessed using regression analysis, centered RMSE and bias. More than 75% of the solutions reconstructed the PM mass satisfactorily. The majority of participants reported between 7 and 11 source/factors. They were classified into 15 different source categories: biomass burning, gasoline, diesel, brakes, traffic, dust, sulphates, nitrates, Zn smelter, Cu metallurgy, Pb smelter, steel processing, industry & combustion, ship emissions, secondary. The inclusion of every source/factor into a category was checked by comparing its chemical profile and time trend with all the other members of the same category and with reference source profiles, when available. The SCEs of the different solutions were compared with a reference value obtained by robust analysis (standard ISO 5725-5). The acceptability criterion was set to 50% relative standard uncertainty. For more details see Karagulian & Belis (2012, IJEP accepted for publication). More than 90% of the 160 assessed source/factor contribution estimations met the acceptability criterion. Although no absolute reference values can be used in real-world DBs, a reasonable quantitative agreement in the SCEs is pointed out by these results. Indeed, the noise of experimental data, the variety of methodological approaches and the fact that the sampling site was completely unknown to participants (particularly crucial for those using CMB) shall be taken into account when interpreting the intercomparison outcome