Recently, associate researcher Sun Dong of the SIO and the co-authors, published the paper entitled “PAHs in the monsoonal open ocean: Homogeneous spatial pattern and wind-driven significant seasonal variations” in the Journal of Hazardous Material (Zone 1, Top), a top-notch international journal in the field of environment. In this study, a method for quantifying the effect of atmospheric transport on PAHs distribution in the open ocean using wind frequency and wind speed weighted wind frequency was developed based on the survey data of multiple voyages in the Philippine Sea, and the effectiveness of this method was further verified using the PAHs public data from the South China Sea and the North Indian Ocean. The results indicate that wind frequency can better explain the changes in dissolved and particulate PAHs in the surface ocean, while wind speed weighted wind frequency can better explain the changes in particulate PAHs. This study indicates that the impact of seasonal atmospheric transport cannot be ignored when analyzing the distribution characteristics of PAHs in monsoonal mid- and low-latitude open ocean, which also provides a reference method for better understanding the global distribution of PAHs.

The first author of the paper is Zhang Linjie, a postgraduate jointly trained by the SIO and Chongqing University, the corresponding author is associate researcher Sun Dong, and the SIO is the first unit and the corresponding author unit. This study received joint funding from the National Natural Science Foundation of China (42076122) and the National Oceanic Program (DY-XZ-02; DY135-E2-3-04).

Figure 1. The concentration and variation coefficient of PAHs in tropical and northern hemisphere open ocean exhibit strong latitudinal gradient variations (offshore data has been excluded). The atmospheric transport model constructed in this study can well explain these spatiotemporal variations.

The model based on wind frequency and wind speed weighted wind frequency proposed in this study:

Where, CPAHs refers to the concentration of dissolved or particulate PAHs (ng/L); fN(n) is the northerly wind frequency from n days ago to the sampling day; fW(n) is the westerly wind frequency from n days ago to the sampling day.

Where, CPAHs refers to the concentration of dissolved or particulate PAHs (ng/L); fwN(n) is the average wind speed weighted northerly wind frequency, using data from n days ago to the sampling day; fwS(n) is the average wind speed weighted southerly wind frequency, using data from n days ago to the sampling day; fwW(n) is the average wind speed weighted westerly wind frequency, using data from n days ago to the sampling day; fwE(n) is the average wind speed weighted easterly wind frequency, using data from n days ago to the sampling day.

In addition, associate researcher Sun Dong and the co-authors recently proposed a new viewpoint that the community structure and particle size structure of zooplankton should not be ignored when studying the migration and transformation behavior of persistent organic pollutants in the ocean by comprehensively using the particle size scanning research method of zooplankton and the high sensitivity analysis method of PAHs. The research paper entitled “Considering zooplankton as a black box in determining PAH concentrations could result in misjudging their bioaccumulation” was published in Environmental Pollution (Zone II, Top), an important journal in the field of environment.

Paper Citation:

1) Zhang, L., Zhang, L., Shi, Y., Yang, Z., Gong, Q., Sun, D.* 2023. PAHs in the monsoonal open ocean: homogeneous spatial pattern and wind-driven significant seasonal variations. Journal of Hazardous Materials, 454, 131462.

2) Zhang, L., Zhang, L., Sun, D.* 2023. Considering zooplankton as a black box in determining PAH concentrations could result in misjudging their bioaccumulation. Environmental Pollution 316, 120672.