When Do Subpollen Particles Become Relevant for Ice Nucleation Processes in Clouds?
When Do Subpollen Particles Become Relevant for Ice Nucleation Processes in Clouds?
复制标题
子花粉颗粒何时与云中的冰核过程相关？
DOI：
10.1029/2021jd036340
复制
发表时间：
2022
期刊：
影响因子：
--
通讯作者：
B. Vogel
中科院分区：
文献类型：
--
作者：
Sven Werchner;Edsl. Gute;C. Hoose;C. Kottmeier;A. Pauling;H. Vogel;B. Vogel
当暴露在足够潮湿的环境中时，花粉粒破裂并释放出大量携带冰核大分子的小亚花粉颗粒（SPPs）。在这项研究中，我们第一次开发了一个物理为基础的参数化描述花粉的爆裂过程中，通过应用膨压参数化和量化的影响SPPs的整体云冰成核。SPP是从欧洲上空的模拟桦树花粉排放中产生的，用于春季为期10天的案例研究。我们发现SPP浓度超过花粉粒浓度4-6个数量级，导致SPP在103−104 m−3范围内丰富的生物冰核。然而，它被发现，这些浓度导致水凝物数密度和降水只有很小的变化。为了解决这个问题，当SPPs成为相关的云冰成核，我们进行了敏感性调查。我们发现，放大生物粒子的冰成核效率的因素大于100增加了冰粒子数高达25%（T = 268 K）。在这些温度下，云滴数、浓度和水蒸气都有明显的减少，而在600米处，水蒸气则有增加的趋势。总的来说，我们发现大气中的水净减少，因为液体，特别是水蒸气密度降低，而冷冻水的质量密度在257 K以上增加。研究结果表明，当SPP被认为是高效的生物冰核时，混合相云成分和降水量增加（高达6.2%）发生了变化。
When exposed to sufficiently humid environments, pollen grains burst and release large quantities of small subpollen particles (SPPs) which carry ice nucleating macromolecules. In this study, for the first time we develop a physically based parameterization describing the bursting process of pollen by applying a turgor pressure parameterization and quantify the impact SPPs have on overall ice nucleation in clouds. SPPs are generated from simulated birch pollen emissions over Europe for a 10‐day case study in spring. We found SPP concentrations to surpass pollen grain concentrations by 4–6 orders of magnitude leading to an abundance of biological ice nuclei from SPPs in the range of 103−104 m−3. However, it is found that these concentrations lead to only small changes in hydrometeor number densities and precipitation. Addressing the question when SPPs become relevant for ice nucleation in clouds, we conducted a sensitivity investigation. We find that amplifying ice nucleation efficiency of biological particles by factors greater 100 increases the ice particle numbers by up to 25% (T ≈ 268 K). Strong reductions show in cloud droplet number concentration and water vapor at these temperatures while water vapor is increasing at 600 m. Overall, we found a net reduction of water in the atmosphere as liquid and particularly water vapor density is reduced, while frozen water mass density increases above 257 K. Findings indicate an alteration of mixed‐phase cloud composition and increased precipitation (up to 6.2%) when SPPs are considered as highly efficient biological ice nuclei.
影响因子：
14.2
作者：
Bacsi, Attila;Choudhury, Barun K.;Boldogh, Istvan
通讯作者：
Boldogh, Istvan
影响因子：
4.9
作者：
Zhang, R.;Duhl, T.;VanReken, T. M.
通讯作者：
VanReken, T. M.