Exploring aerosol–cloud interactions in liquid-phase clouds over eastern China and its adjacent ocean using the WRF-Chem–SBM model

Atmospheric chemistry and physics, vol. 24, pp. 9101–9118

Abstract

In this study we explore aerosol–cloud interactions in liquid-phase clouds over eastern China (EC) and its adjacent ocean (ECO) using the WRF-Chem–SBM model with four-dimensional assimilation. The results show that our simulations and analyses based on each vertical layer provide a more detailed representation of the aerosol–cloud relationship compared to the column-based analyses which have been widely conducted previously. For aerosol activation, cloud droplet number concentration ( N d ) generally increases with aerosol number concentration ( N aero ) at low N aero and decreases with N aero at high N aero . The main difference between EC and ECO is that N d increases faster in ECO than EC at low N aero due to abundant water vapor, whereas at high N aero , when aerosol activation in ECO is suppressed, N d in EC shows significant fluctuation due to strong surface effects (longwave radiation cooling and terrain uplift) and intense updrafts. Cloud liquid water content (CLWC) increases with N d , but the increase rate gradually slows down for precipitating clouds, while CLWC increases and then decreases in non-precipitating clouds. Higher N d and CLWC can be found in EC than in ECO, and the transition-point N d value at which CLWC in non-precipitating clouds changes from increasing to decreasing is also higher in EC. Aerosol activation is strongest at moderate N aero , but CLWC increases relatively fast at low N aero . ECO cloud processes are more limited by cooling and humidification, whereas strong and diverse surface and atmospheric processes in EC allow intense cloud processes to occur under significant warming or drying conditions.

Authors 4

1. Jianqi Zhao

   China Meteorological Administration · Nanjing University of Information Science and Technology

   Affiliation as printed

   China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing 210044, China

2. Xiaoyan Ma corresponding

   Nanjing University of Information Science and Technology

   Affiliation as printed

   Nanjing University of Information Science and Technology (Nanjing, China)

3. Johannes Quaas

   Leipzig University

   Affiliation as printed

   Leipzig Institute for Meteorology, Leipzig University, Leipzig, Germany

4. Hailing Jia Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research, Leiden, the Netherlands