A Synergistic Characterization Method for the Geometric Structure and Optical Response of Non-spherical Aerosols

Atmospheric aerosols represent a critical component of the Earth–atmosphere system, modulating radiative climate forcing through both direct and indirect pathways. Consequently, accurate measurement of their physical and optical properties has long been a primary focus of international aerosol research. Nevertheless, substantial uncertainties persist in current observational techniques and numerical models, particularly with respect to aerosol size distribution, morphology, and optical characteristics. These uncertainties propagate through retrieval algorithms and radiative transfer calculations, ultimately compromising the reliability of radiative forcing estimates and climate projections.
In this study, we address the challenge of characterizing non-spherical aerosol particles through advanced in situ measurement techniques. We first present a high-resolution aerosol imaging system that integrates optical microscopy with real-time computer-vision analysis (Dong, et al., IEEE Trans. Instrum. Meas., 2025). Leveraging advanced image processing algorithms, this instrument delivers high spatiotemporal resolution measurements of particle size, morphology, and number concentration, thereby enabling precise quantification of complex, non-spherical geometries and their dynamic evolution.
Complementing the imaging system, we introduce a fully automated laser scattering measurement instrument designed to acquire aerosol scattering phase functions with exceptional angular coverage (5°–357°) and spectral versatility ranging from the ultraviolet to the near-infrared (Dong, et al., Chin. Opt. Lett., 2025). These high-fidelity phase function measurements provide robust constraints on the angular scattering behavior of non-spherical particles.
By integrating these two complementary platforms, we achieve comprehensive characterization of aerosol particles across a diameter range of 0.2-186 μm. The resulting dataset includes five size descriptors, four independent shape descriptors, scattering phase functions, scattering coefficients, asymmetry parameters, and number concentrations spanning 0 to 10⁸ particles/cm³. Collectively, this synergistic observational framework yields concurrent, high-accuracy determinations of aerosol geometric and optical properties.
These laboratory- and field-validated observations obtained from our integrated systems are expected to substantially reduce uncertainties in radiative transfer simulations, improve estimates of aerosol radiative effects, and deepen our understanding of aerosol–radiation–cloud interactions.

Refs:
1. Li Dong, Yong Han, Maohai Hu, et al. Fast Atmospheric Aerosol Size and Shape Imaging Instrument: Design, Calibration, and Intelligent Interaction[J]. IEEE Transactions on Instrumentation and Measurement, 2025, 74: 1-17.
2. Li Dong, Yong Han, and Yurong Zhang. Development of a multi-wavelength near-full-angle aerosol scattering phase function laser measurement system[J]. Chinese Optics Letters, 2025, 23(11): 111203.