Hartmann Susan, Schrödner Roland, Hassett Brandon T, Hartmann Markus, van Pinxteren Manuela, Fomba Khanneh Wadinga, Stratmann Frank, Herrmann Hartmut, Pöhlker Mira, Zeppenfeld Sebastian
Department of Atmospheric Microphysics (AMP), Leibniz Institute for Tropospheric Research (TROPOS), Leipzig 04318, Germany.
Department of Modeling Atmospheric Processes (MOD), Leibniz Institute for Tropospheric Research (TROPOS), Leipzig 04318, Germany.
Environ Sci Technol. 2025 Mar 18;59(10):5098-5108. doi: 10.1021/acs.est.4c08014. Epub 2025 Mar 7.
Remote marine regions are characterized by a high degree of cloud cover that greatly impacts Earth's radiative budget. It is highly relevant for climate projections to represent the ice formation in these clouds. Therefore, it is crucial to understand the sources of ice-nucleating particles (INPs) that enable primary ice formation. Here, we report polysaccharides produced by four different aquatic eukaryotic microorganisms (, , , ) as responsible ice-nucleating macromolecules (INMs) in these samples originating from the marine biosphere. By deriving a classical nucleation theory-based parametrization of these polysaccharidic INMs and applying it to global model simulations, a comparison to currently available marine atmospheric INP observations demonstrates a 44% contribution of polysaccharides to the total INPs of marine origin within -15 to -20 °C. The results highlight the relevance of biological INMs as part of the INP population in remote marine regions.
偏远海洋区域的特点是云层覆盖度高，这对地球辐射收支有很大影响。对于气候预测而言，准确呈现这些云层中的冰形成过程至关重要。因此，了解促成初次冰形成的冰核粒子（INP）来源至关重要。在此，我们报告了四种不同的水生真核微生物（ 、 、 、 ）产生的多糖，它们是这些源自海洋生物圈的样本中起作用的冰核大分子（INM）。通过基于经典成核理论推导这些多糖类INM的参数化，并将其应用于全球模型模拟，与当前可用的海洋大气INP观测结果进行比较表明，在-15至-20°C范围内，多糖对海洋源总INP的贡献为44%。结果突出了生物INM作为偏远海洋区域INP群体一部分的重要性。
