Marine Carbohydrates and Other Sea Spray Aerosol Constituents Across Altitudes in the Lower Troposphere of Ny-Ålesund, Svalbard

Marine carbohydrates are produced by a wide range of micro- and macroorganisms in seawater and are transferred to the atmosphere via sea spray aerosol (SSA). Recent laboratory and modelling studies suggest that these compounds can influence fog and cloud microphysics as ice nucleating particles. However, observational evidence from the atmosphere remains limited, as most field studies have relied on ship- or land-based filter samples, leaving their relevance for cloud processes at cloud-relevant altitudes largely unconstrained.

Here, we present new measurements of marine carbohydrates and other SSA components at altitudes between 300 and 1200 m, obtained using a tethered helium balloon in Ny-Ålesund (Svalbard) during 2021-2022. These observations are compared with fresh SSA directly collected at the Kongsfjorden coast and with surface seawater samples to assess contributions beyond local ocean emissions. Our results highlight the key role of meteorological conditions in lifting and redistributing SSA constituents, including marine carbohydrates, to higher atmospheric layers. The study further examines potential additional sources and formation pathways, providing new insights into the atmospheric behaviour of marine carbohydrates and their implications for cloud microphysics.

We gratefully acknowledge the funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)—Project Number 268020496—TRR 172, within the framework of the Transregional Collaborative Research Center “ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes, and Feedback Mechanisms (AC)3”