Land-Ocean Interaction Affected by the Monsoon Regime Change in Western Taiwan Strait

Abstract

The Taiwan Strait is a conduit between East China Sea (ECS) and South China Sea (SCS). Seasonal monsoon winds drive the southbound Zhejiang-Fujian Coastal Current and northbound SCS Warm Current through the strait. Water masses carried by these major current systems also carry fluvial signals from two major rivers, the Changjiang (Yangtze) River in ECS and the Zhujiang (Pearl) River in SCS through the strait. Here we show a switch occurred to signify the monsoon regime change on the western side of this conduit around 10:00 on May 8, 2015. Our data came from water mass properties and environmental proxies of N/P ratio in the surface water and 7Be and 210Pbex isotopes in surface sediments. The timings of the demarcation were identical in the water column and on the water-sediment interface. Our findings put a specific time point in the monsoon regime change in 2015.

Deciphering organic matter distribution by source-specific biomarkers in the shallow Taiwan Strait from a source-to-sink perspective

“…Tao et al 10.3389/fmars.2022.969461 whereas silt and sand along the middle and eastern TS originate from Taiwan Island (Xu et al, 2009;Huh et al, 2011;Liu et al, 2018). Recent studies point out a remote source for nutrients and suspended particles to the TS driven by the Pearl River estuarine plumes mixing with the SCSWC crossing the TWB and entering the TS in summer (Liu et al, 2019;Yang et al, 2021). The coastal upwelling usually occurs along the west coast triggered by the prevailing SW summer monsoon, which supplements nutrients…”

“…Because of the high visual resemblance nature of the measured variables, an EOF analysis was used to characterize the correlations (standardized covariability) of multiple variables in the TS. This technique is based on internal correlations (Resio and Hayden, 1975), which present the statistical characteristics of a group of data through the spatial or temporal correlation of the data (Hong et al, 2009;Liu et al, 2019;Yang et al, 2021). Each eigenmode in the EOF result was ranked according to the quotient between the eigenvalue of the eigenmode and the sum of all the eigenvalues.…”

“…The TS is a narrow and shallow conduit linking two major Asian marginal seas with wide shelves dominated by distal Yangtze River and Pearl River fluvial sources. From the source-to-sink (S2S) perspective, this conduit is subject to seasonal monsoons and episodic deliveries of OM from several contrasting sources (Yang et al, 2021). Suspended particles exported from these rivers are transported by monsoonregulated currents: the southbound ZMCC (Liu et al, 2021a) and the northbound South China SCSWC into the TS (Yang et al, 2021).…”

“…From the source-to-sink (S2S) perspective, this conduit is subject to seasonal monsoons and episodic deliveries of OM from several contrasting sources (Yang et al, 2021). Suspended particles exported from these rivers are transported by monsoonregulated currents: the southbound ZMCC (Liu et al, 2021a) and the northbound South China SCSWC into the TS (Yang et al, 2021). ZMCC brings cold water mass and SCSWC brings warm water mass to the TS (Yang et al, 2021).…”

“…Suspended particles exported from these rivers are transported by monsoonregulated currents: the southbound ZMCC (Liu et al, 2021a) and the northbound South China SCSWC into the TS (Yang et al, 2021). ZMCC brings cold water mass and SCSWC brings warm water mass to the TS (Yang et al, 2021). Numerous small rivers on the western side (Zhejiang-Fujian Coast) and small mountainous rivers on the eastern side (Taiwan Coast) also contribute terrestrial materials into the TS via river plume dispersal (Milliman and Farnsworth, 2013;Lee et al, 2016;Liao et al, 2018).…”