Statistical properties of aerosols and meteorological factors in Southwest China. Issue 16 (25th August 2014)

• Record Type: Journal Article
• Authors: Kang, Ping; Feng, Nan; Wang, Zuwu; Guo, Yangjie; Wang, Zhen; Chen, Yarong; Zhan, Jingwen; Zhan, F. Benjamin; Hong, Song
• Is Part Of: Journal of geophysical research. Volume 119:Issue 16(2014)
• Page Start: 9914
• Page End: 9930
• Publication Date: 2014-08-25
• Subjects: Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1002/2014JD022083
• Languages: English
• ISSNs: 2169-897X

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The spatial and temporal variations of aerosols and their relationships with meteorological conditions in Southwest China were studied to understand the aerosol‐meteorology interactions. The spatial distribution of aerosols shows a strong "basin" effect with the highest values of Aerosol Optical Thickness at 0.55 µm (AOT, also denoted τ<sub>0.55</sub>) (>0.70), fine‐mode AOT (τ<sub>0.55‐fine</sub>) (0.40 ~ 0.67), and coarse‐mode AOT (τ<sub>0.55‐coarse</sub>) (0.40 ~ 0.54), all observed in the Sichuan Basin. The temporal variation of seasonal mean τ<sub>0.55</sub> shows dissimilar cyclic variations, which is due to the contrary annual cycle trends of seasonal mean τ<sub>0.55‐coarse</sub> (first decrease and then increase) and τ<sub>0.55‐fine</sub> (first increase and then decrease). Both the results obtained from self‐organizing map (SOM) model and principal component analysis (PCA) could imply the reasons for different features of the spatial and temporal variations of τ<sub>0.55</sub>, τ<sub>0.55‐fine</sub>, and τ<sub>0.55‐coarse</sub>, and also confirm that their distributions are influenced by complex interactions among different meteorological factors. The seasonal mean τ<sub>0.55</sub> during the selected period is positively correlated with air pressure (PRS) and relative humidity (RHU) but negatively correlated with sunshine duration (SSD). The seasonal mean τ<sub>0.55‐fine</sub> is positively correlated with PRS, RHU, average temperature (TEM), and precipitation (PRE). However, the seasonal mean τ<sub>0.55‐coarse</sub> is only negatively correlated with PRE and evaporation (EVP). In particular, the τ<sub>0.55‐fine</sub> increases (decreases) and τ<sub>0.55‐coarse</sub> decreases (increases) with increasing (decreasing) TEM and PRE. This discrepant trend of τ<sub>0.55‐fine</sub> and τ<sub>0.55‐coarse</sub> might account for the weak relationships between τ<sub>0.55</sub> and these two meteorological factors.</p> </abstract>