The Distribution of Aerosols and Their Impacts on Chlorophyll‐ a Distribution in the South China Sea

The distribution of aerosols and their impacts on chlorophyll‐ a (Chl‐ a ) distribution were studied in the South China Sea (SCS). Seventeen years of aerosol optical depth (AOD) data, Chl‐ a concentration data, wind speed (WS), and sea surface temperature (SST) from satellite observations were employed along with 2 years of in situ aerosol total suspended particulates (TSP), total nitrogen, NO 3 − , and NH 4 + data in this study. The results showed that under the influence of the Asian monsoon, the AOD values were higher during the winter (>0.12) and lower during the summer (<0.09). Higher aerosol levels were strongly associated with stronger wind conditions ( r  = 0.70 [AOD vs. WS]; r  = 0.67 [TSP vs. WS]). This study also revealed that Chl‐ a concentrations were strongly modulated by aerosol deposition in SCS. Multiple correlation analyses between monthly Chl‐ a and environmental conditions (i.e., AOD, SST, and WS) in the SCS showed that the Chl‐ a were highly correlated with AOD ( r  = 0.31) and WS ( r  = 0.47). The higher partial correlation coefficients of Chl‐ a with AOD and WS suggested that WS played the most important role, followed by AOD. Aerosol deposition was therefore a main factor besides wind that determined the availability of nutrients at the surface ocean in the SCS, modulating the distribution of Chl‐ a . The contribution of nutrients (i.e., NO 3 − and NH 4 + ) from aerosol dry and wet deposition to new production in the SCS accounted for approximately 10.32% to 28.87%.