Shifts in MJO behavior enhance predictability of subseasonal precipitation whiplashes
Tat Fan Cheng, Bin Wang, Fei Liu, Guosen Chen, Mengqian Lu
Abstract
Subseasonal precipitation whiplashes, marked by sudden shifts between dry and wet extremes, can disrupt ecosystems and human well-being. Predicting these events two to six weeks in advance is crucial for disaster management. Here, we show that the propagation diversity of the Madden-Julian Oscillation (MJO)—a key source of subseasonal predictability—will alter under anthropogenic warming. This is evidenced by a 40% increase in fast-propagating events by the late 21st century. Fast-propagating MJOs may rise in a period as early as 2028–2063, increasing the global risk of precipitation whiplashes through teleconnections. We propose a heuristic framework diagnosing that MJO’s acceleration is primarily driven by enhanced atmospheric stabilization and El Niño-like sea surface warming. The expected rise in fast-propagating MJOs could improve the predictability of subseasonal weather whiplashes, offering critical lead time for disaster preparedness. Understanding these impending shifts is essential for enhancing subseasonal prediction capabilities. This study shows that climate change will significantly increase the frequency of fast Madden-Julian Oscillation (MJO) events by 40%, resulting in more frequent sudden shifts between dry and wet extremes globally. This increase is primarily driven by enhanced atmospheric stabilization and El Niño-like sea surface warming.