Characterization of Cold Wave Paths in the Laizhou Bay Area

The coastal regions of Laizhou Bay are highly susceptible to cold surges. This study used ERA5 reanalysis data from 2007 to 2022 and employed a hybrid model that integrates single-particle Lagrangian trajectories to statistically analyze the paths and intensity characteristics of cold surges in the Laizhou Bay area. Based on this analysis, a comparative analysis of outbreak processes, formation mechanisms, and causes of three different types of cold surge pathways was conducted. Results indicate variations in the characteristics of different cold surge pathways. Cold surges along the northern pathway originate from the Kara Sea. From a circulation perspective, the presence of a warm ridge over the Ural Mountains leads to the formation of a blocking system and an inverted ‘Ω’ flow pattern over Siberia. In contrast, cold surges along the northwest pathway originate from the Barents Sea, the Kara Sea, and the plains of Eastern Europe, with a pre-outbreak circulation displaying a characteristic ‘ridge–trough–ridge’ pattern. Finally, cold surges along the western pathway originate from the Norwegian Sea and the nearby plains of Eastern Europe, transitioning from a blocking pattern to a ‘ridge–trough–ridge’ pattern before the outbreak, distinguishing them from the northern and northwest pathways. This research provides a basis for forecasting cold surge events in Laizhou Bay and for disaster prevention and mitigation in the coastal regions.