Study on visibility forecast optimization based on aerosol- meteorological feedbacks in wet conditions

To quantitatively express the influence of aerosol meteorological feedback on the visibility prediction deviation, especially for the large deviation in the high humidity environment, a visibility prediction method considering aerosol meteorological feedback is proposed in this paper. First, WRF-Chem model is set up in three sensitivity tests with or without aerosol meteorological feedback. Then, the comparison between the simulation results in different tests and the observed data is presented, which verifies the effectiveness of the model. The visibility in different experiments is calculated by using the improvement empirical formula which is affected by both relative humidity and pollutant levels. And the simulation results under different conditions are compared, thus quantifying the influence of aerosol meteorological feedback effect on the spatiotemporal distribution of simulated visibility. The results show that considering the complete aerosol meteorological feedback can narrow the gap of deviation in atmospheric relative humidity value, and the error of the relative humidity is reduced from 11.33% to 3.88%, indicating improvement of the simulation. Compared with the observed values, the standardized mean deviation of the simulated visibility values decreases from 4.23%, 13.53%, 14.31%, and 12.38% to −0.64%, 8.65%, 1.14%, and 8.06%, in different seasons (in January, April, July and October) respectively. The data with high humidity (>80%) background are selected for further analysis. The results show that under the high humidity weather environment, the standardized mean deviation of the visibility can be reduced by 11.34% considering the complete meteorological feedback process, which implies improvement of the accuracy of the visibility prediction. •We conducted three sensitivity experiments with the WRF-Chem model to advance our understanding of atmospheric processes. The experiments aimed to explore and quantify the differences between aerosol-cloud feedback and aerosol-radiation feedback, highlighting their individual impacts on atmospheric dynamics and aerosol loading.•Our study investigated how humidity affects the accuracy of visibility simulations under aerosol-meteorological feedback. We closely examined the complex interplay between humidity, PM2.5, and visibility. Significantly, our results show that simulations including aerosol feedback had the lowest average and standardized biases for visibility predictions, especially in humid con