Origin and distribution of the floating Sargassum in the Yellow and East China Sea

Abstract

Using particle tracking modeling and satellite data, the origin and pathway of the floating Sargassum reaching southwestern part of Korea were investigated. The study revealed that the Sargassum was not only from the Zhejiang coast of the East China Sea (ECS) but also from the northern coast of the Yellow Sea (YS). Particles from the northern coast of the YS origin showed two paths, reaching Jeju Island and the southwestern part of the Korean Peninsula due to the influence of monsoon and coastal currents in winter or moving to the ECS and reaching the area through southerly wind in spring. The timing of arrival at the coast of the Korean Peninsula varies from year to year, but the early arrival of each year was greatly influenced by the westerly wind in December of last year. In relation to the growth of Sargassum, the study highlights the importance of temperature. Between 2010–2022, the surface temperature trend on the coast of China and the ECS was about 10 times higher than that of the past 30 years and 5–6 times the global surface average, indicating that accelerated algae growth and warming of coastal and sea areas are related, and continuous monitoring is necessary.