Marine carbohydrates and other sea spray aerosol constituents across altitudes in the lower troposphere of Ny-Ålesund, Svalbard

Abstract. Marine combined carbohydrates in aerosol particles (CCHOaer) have the potential to influence cloud formation and properties, but it remains unclear to what extent they reach altitudes relevant for cloud processes. Balloon-borne measurements of major sea spray aerosol (SSA) constituents, including sodium (Na⁺aer) and CCHOaer​, were conducted in autumn 2021 and spring 2022 in Ny-Ålesund (Svalbard). Total suspended particles were collected at 321–1112 m, covering both the marine boundary layer and the free troposphere, with Na⁺aer ranging 23–850 ng m-3 and CCHOaer​​ 3.8–274 ng m-3. The chemical composition of balloon-borne aerosol samples was compared with synchronized ground level measurements at the balloon's winch (Na⁺aer: 35–3710 ng m-3; CCHOaer​: 1.9–194 ng m-3), and at the Old Pier (Na⁺aer: 140–1470 ng m-3; CCHOaer​: 1.6–10.0 ng m-3), where freshly emitted SSA particles were sampled. Surface seawater from the Kongsfjorden was analyzed to evaluate the sea-air transfer of marine CCHO. Air mass histories, atmospheric mixing, and cloud conditions were evaluated for three selected cases to explain vertical concentration patterns. A strong correlation (R=0.78, p<0.001) between combined xylose (<0.2–14.1 ng m-3) in CCHOaer​ and oxalateaer (<1–67 ng m-3) across all altitudes, suggests either coproduction or a connection through atmospheric processing. These results provide a first comprehensive picture of local primary sea-air transfer of marine combined carbohydrates and highlight the roles of long-range transport, in-situ formation, and chemical aging in shaping their atmospheric distribution.