Spatiotemporal trends of annual minimum sea surface temperature in the Eastern China seas
摘要
Minimum annual sea surface temperature (Tmin) plays a critical role in shaping marine ecological processes, yet its spatial and temporal variability remains insufficiently understood in many regional seas. This study investigates the spatiotemporal trends of Tmin and its timing in the Eastern China seas from 1985 to 2022. Results reveal distinct spatial patterns, with warming trends (~ 0.3 °C/decade) associated with northward-flowing warm currents, and significant cooling trends (up to − 0.4 °C/decade) along coastal regions influenced by cold coastal currents. Tmin and its timing were strongly correlated with preceding atmospheric conditions from December onward, including air temperature, wind components, and surface heat fluxes. These relationships enabled the development of an artificial neural network model capable of predicting Tmin and its timing with lead times of one to two months. Ecologically, lower Tmin values were associated with increased chlorophyll concentrations and a higher frequency of marine cold spells. These findings offer new insights into the mechanisms driving Tmin variability and highlight its potential predictability, providing a basis for improving early warning systems and supporting ecosystem-based management in a changing climate.