Sources, Occurrence and Characteristics of Fluorescent Biological Aerosol Particles Measured over the Pristine Southern Ocean

Abstract

Primary biological aerosol particles (PBAP) are ubiquitous atmospheric particles emitted from the biosphere, which encompass intact microorganisms (e.g., bacteria, viruses, pollen, fungal spores etc.), or fragments of such microorganisms (Després et al., 2012;Fröhlich-Nowoisky et al., 2016). PBAP have major impacts on public health, as certain types of PBAP are known to act as allergens or spread disease (Després et al., 2012;Fröhlich-Nowoisky et al., 2016;Taylor et al., 2004). Furthermore, long-range transport of PBAP, such as bacteria, could influence the ecosystem and biome diversity of the environments to which they are transported (Burrows et al., 2009;Hervàs et al., 2009;Kellogg & Griffin, 2006). Moreover, PBAP have the potential to affect cloud formation, for example by acting as giant cloud condensation nuclei (Pope, 2010) at low supersaturations. A number of studies have demonstrated that PBAP are effective ice nucleating particles (INP) (Després et al., 2012;Tobo et al., 2013), thereby facilitating glaciation of super-cooled liquid clouds via heterogeneous ice nucleation (Kanji et al., 2017). Such aerosol-cloud interactions can modify cloud optical properties and precipitation patterns with important atmospheric impacts on regional and global scales (Kanji et al., 2017).PBAP originate from both the terrestrial and marine biosphere (Després et al., 2012). In the oceanic environment, primary aerosol particles, known as sea spray aerosol (SSA) particles, are produced through a combination of processes, which includes breaking of waves, generation of bubbles in the oceanic water,

Emission of primary bioaerosol particles from Baltic seawater

“…Furthermore, the corresponding size distribution is centered at 5 ± 2 μm which is similar to the size of bacteria agglomerates previously identified in both ambient coastal aerosol 51 and nascent SSA generated in laboratory experiments. 18,30 Interestingly, a number of recent studies suggest that PBAP constitutes only a small portion of the FP over or close to marine environments 27,49 and our data would appear to corroborate this: the PBAP contribution to the total FP was only 0.46% (0.04% of all CP).…”

“…Recently, several experimental efforts were made to measure PBAP within marine environments [26][27][28] and in laboratory studies 29,30 combining UV-LIF methods with offline measurements such as lter collection. Other studies have also attempted to determine the role of seawater characteristics on the emission of PBAP.…”

Circum-Antarctic abundance and properties of CCN and INP

“…Validation of sizing accuracy of both instruments was performed using polystyrene latex spheres. To minimize influences of the ship exhaust, data filtering was performed for the SMPS and APS data, based on sudden changes in the total aerosol particle number concentration, concentrations of carbon dioxide, black carbon, and wind direction (Moallemi et al, 2021).…”

Biogeochemistry and Physics of the Southern Ocean-Atmosphere System Explored With Data Science

“…The ratio of coarse and fine fluorescent aerosol particles to total aerosol particle numbers in the atmosphere (r fluo,coarse3σ ; r fluo,fine3σ ), which are negatively correlated with LV11 activation, are also linked with bacterial concentrations in the Southern Ocean (Moallemi et al, 2021). The likely source of the fluorescent particles is sea spray enriched with organic matter, specifically bacteria (Moallemi et al, 2021).…”