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<p>Transparent exopolymer particles (TEPs) exhibit the properties of gels and are ubiquitously found in the world oceans. TEPs may enter the atmosphere as part of sea-spray aerosol. Here, we report number concentrations of TEPs with a diameter <span class="inline-formula">&gt;</span> 4.5 <span class="inline-formula">µ</span>m, hence covering a part of the supermicron particle range, in ambient aerosol and cloud water samples from the tropical Atlantic Ocean as well as in generated aerosol particles using a plunging waterfall tank that was filled with the ambient seawater. The ambient TEP concentrations ranged between <span class="inline-formula">7×10²</span> and <span class="inline-formula">3×10⁴</span> #TEP m<span class="inline-formula">⁻³</span> in the aerosol particles and correlations with sodium (<span class="inline-formula">Na⁺</span>) and calcium (<span class="inline-formula">Ca²⁺</span>) (<span class="inline-formula"><i>R</i>²=0.5</span>) suggested some contribution via bubble bursting. Cloud water TEP concentrations were between <span class="inline-formula">4×10⁶</span> and <span class="inline-formula">9×10⁶</span> #TEP L<span class="inline-formula">⁻¹</span> and, according to the measured cloud liquid water content, corresponding to equivalent air concentrations of 2–<span class="inline-formula">4×10³</span> #TEP m<span class="inline-formula">⁻³</span>.</p> <p>Based on <span class="inline-formula">Na⁺</span> concentrations in seawater and in the atmosphere, the enrichment factors for TEPs in the atmosphere were calculated. The tank-generated TEPs were enriched by a factor of 50 compared with seawater and, therefore, in-line with published enrichment factors for supermicron organic matter in general and TEPs specifically. TEP enrichment in the ambient atmosphere was on average <span class="inline-formula">1×10³</span> in cloud water and <span class="inline-formula">9×10³</span> in ambient aerosol particles and therefore about two orders of magnitude higher than the corresponding enrichment from the tank study. Such high enrichment of supermicron particulate organic constituents in the atmosphere is uncommon and we propose that atmospheric TEP concentrations resulted from a combination of enrichment during bubble bursting transfer from the ocean and a secondary TEP in-situ formation in atmospheric phases. Abiotic in-situ formation might have occurred from aqueous reactions of dissolved organic precursors that were present in particle and cloud water samples, whereas biotic formation involves bacteria, which were abundant in the cloud water samples.</p> <p>The ambient TEP number concentrations were two orders of magnitude higher than recently reported ice nucleating particle (INP) concentrations measured at the same location. As TEPs likely possess good properties to act as INPs, in future experiments it is worth studying if a certain part of TEPs contributes a fraction of the biogenic INP population.</p>