近日，南京信息科技大学陆春松团队综合分析了不同气溶胶条件和演化阶段下粒径分布的相对弥散及其与关键物理雾过程的关系。相关论文于2025年8月11日发表在《大气科学进展》杂志上。

云/雾液滴相对弥散对气溶胶间接效应、辐射传递和微物理过程有重要影响。然而，以往的研究主要集中在云上，对雾的研究，特别是对所有关键物理过程和雾演变过程的综合影响的研究有限。研究组旨在通过研究相对弥散与其他微物理变量之间的关系，以及基于污染和清洁条件下的现场雾运动的潜在微物理和动态过程，进行这样一个全面的调查。在被污染的雾中，液滴浓度较高，导致液滴变小，分散加剧。在污染雾中，弥散与雾滴体积-平均半径呈正相关，而在清洁雾中，弥散与雾滴体积-平均半径呈正相关。

研究组将这种差异归因于各种微物理过程，如气溶胶活化、凝结、碰撞-聚结和夹带-混合。在污染雾中，高气溶胶浓度、低过饱和度和强湍流（夹带-混合）为液滴凝结和气溶胶活化同时发生提供了适宜的条件，导致弥散与体积-平均半径呈正相关，尤其是在雾形成阶段。而在洁净雾的成熟阶段，以凝结为主，气溶胶激活弱，导致相对弥散与体积平均半径呈负相关。成熟阶段碰撞-聚结过程更加活跃，使净雾的辐射半径增大，导致散度与体积平均辐射半径呈负相关。这一结果为认识不同气溶胶背景下雾中的相对弥散及其机理提供了新的思路。

附：英文原文

Title: Comprehensive analysis of relative dispersion of the particle size distribution and its relationships to key physical fog processes under different aerosol conditions and evolution stages

Author: Xingcan Jia, Chunsong Lu, Zhiheng Liao, Ping Tian, Wang Yuan, Fei Wang, Shuai YANG, Youjun DOU, Xiange LIU, Yangang Liu

Issue&Volume: 2025-08-11

Abstract: Cloud/fog droplet relative dispersion has important impacts on aerosol indirect effect, radiative transfer, and microphysical processes. However, previous studies have been mostly concerned with clouds, with limited studies on fog, esp., on the combined influences of all the key physical processes and during fog evolution. This study aims for such a comprehensive investigation by examining the relationships between relative dispersion and other microphysical variables, and the underlying microphysical and dynamic processes, based on the field fog campaigns in polluted and clean conditions. In the polluted fog, droplet concentrations are higher, leading to smaller droplets and increased dispersion. The correlation between dispersion and droplet volume-mean radius is positive in the polluted fog, but shifts to negative in clean fog. We attribute the difference to various microphysical processes like aerosol activation, condensation, collision-coalescence, and entrainment-mixing. In the polluted fog, the high aerosol concentration, low supersaturation and strong turbulence (entrainment-mixing) provide suitable conditions for the concurrent occurrence of droplet condensation and aerosol activation, resulting in the positive correlation between dispersion and volume-mean radius, especially during fog formation stage. In contrast, during the mature stage in clean fog, condensation is dominant with weak aerosol activation leading to a negative correlation between relative dispersion and volume-mean radius. The collision-coalescence process is more active in mature stage, increasing radius and leading to the negative correlation between dispersion and volume-mean radius in the clean fog. The result sheds new light on understanding the relative dispersion and mechanisms in fog under different aerosol backgrounds.

DOI: 10.1007/s00376-025-4228-9

Source: http://www.iapjournals.ac.cn/aas/article/doi/10.1007/s00376-025-4228-9