Enhancing extreme weather event classification ensemble machine learning modelling: an application to Mainland Southeast Asia region
摘要
Detecting extreme climate events such as heatwaves, cold spells, and heavy rainfall is crucial for disaster preparedness and risk management. This study develops a multi-model machine learning framework integrating Random Forest (RF), XGBoost (XGB), and Multi-Layer Perceptron (MLP) to classify extreme weather events in mainland Southeast Asia. Using ERA5-Land reanalysis data (0.1° resolution), an ensemble learning approach enhances prediction accuracy and classification stability. Results show that tree-based models (RF and XGB) outperform MLP, achieving perfect precision, recall, F1-score, and accuracy (1.00) across all event categories, while MLP struggles with class imbalance, particularly in detecting heatwaves and heavy rainfall. The ensemble model reduces false positives by 33.3%, improves classification stability by 46.7%, and increases confidence by 10.2%. Feature analysis highlights event intensity and duration as key predictors, with heatwave intensity (0.19) and maximum temperature (0.17) most influential for heatwaves, while minimum temperature (0.14) and cold spell duration (0.13) drive cold spell classification. Rainfall intensity (0.21) and precipitation-temperature interactions (0.18) are crucial for heavy rain detection. Spatial analysis reveals that heatwaves dominate southern lowlands, cold spells concentrate in northern highlands, and heavy rainfall peaks in coastal regions, emphasizing regional climate risks. Long-term trends (1980–2014) indicate rising maximum temperatures (0.01 °C/year) and increasing rainfall variability, intensifying extreme events. This ensemble-based framework supports real-time climate monitoring and early warning systems, with future work focusing on probabilistic forecasting and climate adaptation strategies.