The Impact of Interactions Between Sea Surface Temperature and Tropical Cyclones on Fisheries Activities in the South China Sea

Based on Tropical Cyclones (TCs), Sea SurfaceTemperature (SST), and AIS fishing activity data from 2013 to 2024, this study employs hotspot analysis, Empirical Orthogonal Function (EOF) analysis, and wavelet coherence analysis to investigate the interactions among TCs, SST, and fishing activities in the South China Sea (SCS) from the perspectives of spatial distribution and temporal variation. The results show that fishing hotspots in the SCS are mainly distributed along the western coastal zone and are concentrated in the Pearl River Estuary, the Beibu Gulf, and the Central Western SCS. Among these, the Pearl River Estuary is most severely affected by TCs, while the Beibu Gulf and the Central–Western SCS are relatively less affected. In terms of spatial variability, the interactions among TCs, SST, and Fishing effort can be summarized as follows: in summer and autumn, the relatively high SST on the eastern side of the SCS provides abundant heat flux and water vapor for the formation and development of TCs; when TCs reach the western coastal waters, they enhance upwelling and terrestrial runoff, forming seasonal upwelling fishing grounds that in turn promote the aggregation of fishing hotspots, while the upwelling effect also exerts a cooling influence on the western coastal waters. In terms of temporal variability, it is inferred that TCs, SST, and Fishing effort are linked through an air–sea coupling mechanism jointly shaped by the summer monsoon and El Niño-Southern Oscillation (ENSO). Tropical cyclones, dominated by the summer monsoon, exert a direct positive impact on Fishing effort, whereas both TCs and Fishing effort exhibit a lagged response to SST changes driven by the combined effects of ENSO and the summer monsoon. The findings provide a scientific basis for fisheries production and management in the SCS.