Showing papers by "Mary K. Gilles published in 2018"
Environmental Molecular Sciences Laboratory1, Pacific Northwest National Laboratory2, Xiamen University3, Lawrence Berkeley National Laboratory4, University of Würzburg5, University of California, Berkeley6, Max Planck Society7, Federal University of São Paulo8, University of São Paulo9, Federal University of Pará10, Purdue University11
TL;DR: It is shown that, during the wet season, fungal spores emitted by the forest biosphere contribute at least 30% (by number) to sodium salt particles in the central Amazon basin.
Abstract: In the Amazon basin, particles containing mixed sodium salts are routinely observed and are attributed to marine aerosols transported from the Atlantic Ocean. Using chemical imaging analysis, we show that, during the wet season, fungal spores emitted by the forest biosphere contribute at least 30% (by number) to sodium salt particles in the central Amazon basin. Hydration experiments indicate that sodium content in fungal spores governs their growth factors. Modeling results suggest that fungal spores account for ~69% (31-95%) of the total sodium mass during the wet season and that their fractional contribution increases during nighttime. Contrary to common assumptions that sodium-containing aerosols originate primarily from marine sources, our results suggest that locally-emitted fungal spores contribute substantially to the number and mass of coarse particles containing sodium. Hence, their role in cloud formation and contribution to salt cycles and the terrestrial ecosystem in the Amazon basin warrant further consideration.
37 citations
TL;DR: In addition to their direct interactions with sunlight through scattering and absorption, aerosol particles also act as nuclei forming clouds in the atmosphere as discussed by the authors, and these aerosol-cloud interactions are inadequately understood.
Abstract: Understanding the composition and physical properties of atmospheric particles is important to model their effects on climate radiative forcing. In addition to their direct interactions with sunlight through scattering and absorption, aerosol particles also act as nuclei forming clouds in the atmosphere. Overall, these aerosol-cloud interactions are inadequately understood. [1] The particle composition in the atmosphere varies by altitude and is different between the boundary layer and the free troposphere. Sources of aerosol particles in the eastern North Atlantic range from sea spray to new particle formation events from gas-particle conversion. Micron-size particles consist of primarily sea salt mixed with marine non-volatile organics, while the submicron size particles are dominated by organics from the ocean surface. [2]