Ke et al. (2025) Influence of boundary layer-cloud coupling on cloud microphysics based on aircraft observations in the North China plain

Identification

• Journal: The Science of The Total Environment
• Year: 2025
• Date: 2025-10-06
• Authors: Yue Ke, Sihan Liu, Honglei Wang, Yang Yang, Yong Hu, Xiang Li, Yi Cui, Zihao Wu, Zihan Wang, Tianliang Zhao
• DOI: 10.1016/j.scitotenv.2025.180679

Research Groups

• China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing, China
• Hebei Provincial Weather Modification Office, Shijiazhuang, Hebei Province, China

Short Summary

This study utilized 35 aircraft observations over the North China Plain from 2019 to 2021 to investigate the vertical and spectral distributions of aerosols and cloud microphysical variables, revealing how boundary layer-cloud coupling influences cloud microphysics and aerosol characteristics.

Objective

• To investigate the vertical and spectral distributions of aerosols and cloud microphysical variables using aircraft observations over the North China Plain.
• To analyze the influence of boundary layer-cloud coupling mechanisms (coupled vs. decoupled) on cloud microphysics and aerosol characteristics.

Study Configuration

• Spatial Scale: North China Plain (NCP)
• Temporal Scale: 2019 to 2021 (3 years)

Methodology and Data

• Models used: Not applicable; this study is based on observational data.
• Data sources: 35 aircraft observations (21 in cloudy conditions)

Main Results

• Aerosol number concentration (Na) and black carbon mass concentration (MBC) decreased with altitude, stabilizing at 3000 m (winter) and 2000 m (other seasons) in clear sky, and 3500 m in cloudy conditions.
• Na was highest in winter (both clear sky and cloudy) and lowest in summer (clear sky) or spring (cloudy).
• Cloud droplet number concentration (Nc) and liquid water content (LWC) exhibited unimodal vertical profiles across all seasons.
• Ice crystal number concentration (Ni) showed seasonal differences but no distinct vertical trend.
• The cloud droplet size distribution (dNc/dD) peaked at 6.5 µm, while the ice crystal size distribution (dNi/dD) displayed bimodal peaks at 125 µm and 1500 µm.
• Among the 21 cloudy observations, 15 were decoupled and 6 were coupled.
• Decoupled clouds were primarily influenced by downward air masses originating outside the NCP, whereas coupled clouds were influenced by upward air masses from within the NCP.
• In spring, the concentration of cloud droplets with diameters greater than 27 µm was higher in coupled clouds, while droplets with diameters greater than 8.5 µm were lower in decoupled clouds.
• The derivative of ice crystal number concentration with respect to diameter (dNi/dD) for all diameters was relatively higher in decoupled clouds during autumn.
• Cloud base height (Hbase) is sensitive to both vertical velocity (ω) and relative humidity (RH), while cloud base entrainment rate (Ed) is predominantly controlled by vertical velocity (ω).

Contributions

• Provides a comprehensive observational dataset of vertical and spectral distributions of aerosols and cloud microphysical properties over the North China Plain using aircraft measurements.
• Quantifies the distinct impacts of boundary layer-cloud coupling (coupled vs. decoupled) on aerosol characteristics and cloud microphysics, including droplet and ice crystal size distributions, across different seasons.
• Identifies the primary meteorological factors (vertical velocity and relative humidity) governing cloud base height and entrainment rate in the region.

Funding

Not specified in the provided text.

Citation

@article{Ke2025Influence,
  author = {Ke, Yue and Liu, Sihan and Wang, Honglei and Yang, Yang and Hu, Yong and Li, Xiang and Cui, Yi and Wu, Zihao and Wang, Zihan and Zhao, Tianliang},
  title = {Influence of boundary layer-cloud coupling on cloud microphysics based on aircraft observations in the North China plain},
  journal = {The Science of The Total Environment},
  year = {2025},
  doi = {10.1016/j.scitotenv.2025.180679},
  url = {https://doi.org/10.1016/j.scitotenv.2025.180679}
}