2024年初中国东部严重冻雨事件的机理与次季节预测研究

Key Points

• This research aims to understand the mechanisms behind severe freezing rain in Eastern China and evaluate prediction capabilities.
• Utilized reanalysis data and model forecasts to establish grid-point freezing rain identification methods.
• Conducted diagnostics to analyze causes of freezing rain events in February 2024.
• Evaluated existing models for subseasonal to seasonal (S2S) prediction accuracy of freezing rain events.
• Findings indicate that severe freezing rain was triggered by excessive precipitation anomalies and deep inversion layers.
• Specified necessary conditions for freezing rain, highlighting the role of enhanced Siberian high pressure and its weak correlation with event intensity.
• Predictions show that current models can forecast freezing rain events only 2-3 days in advance due to insufficient representation of Siberian high pressure and cold air activities.