Linkage between Record Floods in Pakistan and a Severe Heatwave in China in the Boreal Summer of 2022

AbstractIn the boreal summer of 2022, Pakistan suffered record rainfall that led to severe flooding and left more 30 million people homeless. At the same time, a severe heatwave persisted over central China. The concurrence of these extreme events suggests a possible linkage. Our analysis of climatic data indicated that the record rainfall was triggered by an extratropical cold-dry northerly associated with European blocking interacting with an unusually strong warm-moist southerly flow from the Arabian Sea at Pakistan. Both flows joined with an easterly anomaly induced by La Niña over the northern Indian subcontinent, which resulted in strong convergence. Wave activity flux analysis indicated that the European blocking, flooding in Pakistan, and heatwave in China were teleconnected by a stationary Rossby wave-like pattern. The rainfall in Pakistan may have induced diabatic heating that forced an upper-level anomalous anticyclone downstream and strengthened the heatwave in central China.