Dimethyl sulfide air-sea fluxes and biogenic sulfur as a source of new aerosols in the Arctic fall

Abstract

Dimethyl sulfide (DMS) and its oxidation products, which have been proposed to provide a climate feedback mechanism by affecting aerosol and cloud radiative properties, were measured on board the Canadian Coast Guard ship Amundsen in sampling campaigns in the Arctic in the fall of 2007 and 2008. DMS flux was calculated based on the surface water measurements and yielded 0.1–2.6 μmol m−2 d−1 along the Northwest Passage in 2007 and 0.2–1.3 μmol m−2 d−1 along Baffin Bay in 2008. DMS oxidation products, sulfur dioxide (SO2), methane sulfonic acid (MSA), and sulfate in aerosols were also measured. The amounts of biogenic SO2 and sulfate were approximated using stable isotope apportionment techniques. Calculating the threshold amount of SO2 needed for significant new particle formation from the formulation by Pirjola et al. (1999), the study suggests that instances of elevated biogenic SO2 concentrations (between 8 and 9 September 2008) derived using conservative assumptions may have been sufficient to form new aerosols in clean air conditions in the Arctic region.

Biogenic, anthropogenic and sea salt sulfate size-segregated aerosols in the Arctic summer

“…Although wind is considered an important factor in the seaair exchange of sea salt, correlations in this study between wind speed and sea salt sulfate concentrations for coarse-and fine-mode aerosols were not significant (R 2 ∼ = 0.1), which is consistent with previous studies (Lewis and Schwartz, 2004;Rempillo et al, 2011;Seguin et al, 2011;Jaeglé et al, 2011).…”

“…Results show approximately uniform non-sea-salt sulfate concentrations for samples in the Labrador Sea and further north (130 ± 21 ng m −3 ). Sulfate concentrations, especially nonsea-salt sulfate, in this research were found to be higher than previous Arctic studies above the ocean during fall (2007)(2008) (Rempillo et al, 2011) and at higher latitudes at Alert in summer (1993)(1994) (Norman et al, 1999) and about the same as at Barrow, Alaska during July (1997-2008) (Quinn et al, 2009). One reason could be higher biological activity and biogenic aerosols from phytoplankton during summer, as addressed in the next section.…”

“…Non-seasalt sulfate is divided into biogenic and anthropogenic sulfate using stable isotope apportionment techniques. A considerable amount of the average sulfate concentration in the fine aerosols with a diameter < 0.49 µm was from biogenic sources (> 63 %), which is higher than in previous Arctic studies measuring above the ocean during fall (< 15 %) (Rempillo et al, 2011) and total aerosol sulfate at higher latitudes at Alert in summer (> 30 %) (Norman et al, 1999). The anthropogenic sulfate concentration was less than that of biogenic sulfate, with potential sources being long-range transport and, more locally, the Amundsen's emissions.…”

“…These methods may overestimate the role of biogenic sources if anthropogenic sulfate is present. The isotopic differences of various sources present a way to determine the oceanic DMS contribution to aerosol growth (Norman et al, 1999(Norman et al, , 2004Seguin et al, 2010Seguin et al, , 2011Rempillo et al, 2011). Sizesegregated aerosols were collected in July 2014 during an extended transect going from the strait of Belle Isle to Lancaster Sound in the Canadian Arctic, permitting comparison with measurements from other seasons.…”

Anorganski spojevi sumpora u ljudskom tijelu. I. Okso-spojevi.

“…109 U prirodi nastaje iz antropogenih, geogenih, biogenih i fotokemijskih izvora. [108][109][110] Glavni antropogeni izvori su proizvodnja energije, industrija, termoelektrane, promet, spaljivanje otpada. Geogeni izvori uključuju vulkane i termalne izvore, dok biogeni obuhvaćaju hlapljive organske spojeve bogate sumporom koji odlaze u atmosferu gdje se iz njih proizvodi SO 2 .…”