Source apportionment of the organic aerosol over the Atlantic Ocean from 53° N to 53° S: significant contributions from marine emissions and long-range transport

Abstract

Abstract. Marine aerosol particles are an important part of the natural aerosol systems and might have a significant impact on the global climate and biological cycle. It is widely accepted that truly pristine marine conditions are difficult to find over the ocean. However, the influence of continental and anthropogenic emissions on the marine boundary layer (MBL) aerosol is still less understood and non-quantitative, causing uncertainties in the estimation of the climate effect of marine aerosols. This study presents a detailed chemical characterization of the MBL aerosol as well as the source apportionment of the organic aerosol (OA) composition. The data set covers the Atlantic Ocean from 53∘ N to 53∘ S, based on four open-ocean cruises in 2011 and 2012. The aerosol particle composition was measured with a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), which indicated that sub-micrometer aerosol particles over the Atlantic Ocean are mainly composed of sulfates (50 % of the particle mass concentration), organics (21 %) and sea salt (12 %). OA has been apportioned into five factors, including three factors linked to marine sources and two with continental and/or anthropogenic origins. The marine oxygenated OA (MOOA, 16 % of the total OA mass) and marine nitrogen-containing OA (MNOA, 16 %) are identified as marine secondary products with gaseous biogenic precursors dimethyl sulfide (DMS) or amines. Marine hydrocarbon-like OA (MHOA, 19 %) was attributed to the primary emissions from the Atlantic Ocean. The factor for the anthropogenic oxygenated OA (Anth-OOA, 19 %) is related to continental long-range transport. Represented by the combustion oxygenated OA (Comb-OOA), aged combustion emissions from maritime traffic and wild fires in Africa contributed, on average, a large fraction to the total OA mass (30 %). This study provides the important finding that long-range transport was found to contribute averagely 49 % of the submicron OA mass over the Atlantic Ocean. This is almost equal to that from marine sources (51 %). Furthermore, a detailed latitudinal distribution of OA source contributions showed that DMS oxidation contributed markedly to the OA over the South Atlantic during spring, while continental-related long-range transport largely influenced the marine atmosphere near Europe and western and central Africa (15∘ N to 15∘ S). In addition, supported by a solid correlation between marine tracer methanesulfonic acid (MSA) and the DMS-oxidation OA (MOOA, R2>0.85), this study suggests that the DMS-related secondary organic aerosol (SOA) over the Atlantic Ocean could be estimated by MSA and a scaling factor of 1.79, especially in spring.

New particle formation and its effect on cloud condensation nuclei abundance in the summer Arctic: a case study in the Fram Strait and Barents Sea

“…half an hour prior to the formation of neutral particles. Although not in the polar regions, similar behavior was noticed in several other studies, suggesting the importance of ions in NPF events (Manninen et al, 2010;Jayaratne et al, 2016). The role of ions in NPF was investigated in both laboratory and field studies (e.g., Wagner et al, 2017;Jokinen et al, 2018).…”

Source Apportionment of Fine Organic and Inorganic Atmospheric Aerosol in an Urban Background Area in Greece

“…This is consistent with its photochemical source. One of the two OOA factors resolved by PMF had contributions at m/z 64 and 80 ( Figure 7), associated with marine OA and more specifically methanesulfonic acid (MSA) [47]. MSA is a product of the atmospheric oxidation of dimethyl sulfide (DMS) emitted by marine phytoplankton.…”

Linking marine phytoplankton emissions, meteorological processes and downwind particle properties with FLEXPART

“…Previous literature hints that phytoplankton activity is related to emissions of organic and sulfate aerosol mass precursors (Altieri et al, 2016;Ayers et al, 1997;Bates et al, 1998b;Brüggemann et al, 2018;Ceburnis et al, 2011;Facchini et al, 2008;Hallquist et al, 2009;Hu et al, 2013;Huang et al, 2018;Mansour et al, 2020;Ovadnevaite et al, 2014;Park et al, 2017;Sanchez et al, 2018). These precursors are emitted over a large area at varying rates due to the spatial and temporal variation of marine biological activity (Behrenfeld, 2010;Behrenfeld and Boss, 2018).…”