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The sediment core DGKS9603 collected from the Okinawa Trough was used as research target. By use of unsaturated index U of long-chain alkenone, δC of POC and of planktonic foraminifera ( G. sacculifer), the evolutions of sea surface temperature and partial pressure of carbon dioxide in the atmosphere during the Holocene were reconstructed in the Okinawa Trough. And in combination of δO of planktonic foraminifera, the relative difference of sea surface salinity during the Holocene was also reconstructed. Consequently, three cooling events (E-E) were identified, each of which occurred at 1.7-1.6, 5.1-4.8 and 8.1-7.4 kaBP (cal), respectively. Of the three events, E and E are globally comparable, their occurrence mechanism would be that the main stream of the Kuroshio Current shifted eastward due to the enhanced circulation of the northeastern Pacific Ocean, which was driven in turn by amplified intensity of sunshine and subsequent enhancement of subtropical high pressure; E corresponds to the Small Ice-Age Event occurring between 1550 and 1850AD in China. In the Oki-nawa Trough, E might be also related to the eastward shift of main stream of the Kuroshio current driven by powerful Asia winter monsoon. [ABSTRACT FROM AUTHOR]

We studied 19 targets currently using organochlorine pesticides (CUOCPs) from 98 samples in the Western Pacific Ocean and the East China Sea collected in 2019, 2020, and 2021. The samples were analyzed using a novel High-throat/High-volume Solid-Phase Extraction method. Eighteen individual CUOCPs were above the method detection limits. The levels of ∑ 19 CUOCPs ranged from 0.13 to 17.80 ng/L, with an average of 3.13 ± 14.67 ng/L. Dicofol was the main pollutant in the Western Pacific Ocean, while Pyridaben dominated the East China Sea. In the summer, land-source input was the primary source in the Western Pacific Ocean and the East China Sea. Historical residues were the main source in the East China Sea in spring. In the summer, the ecological risk assessment results indicated a relatively low risk to the Western Pacific Ocean and the East China Sea., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)