Contrasting dynamical and thermodynamical pathways shaped the 2024 North-Central Indian heatwave

Abstract An unprecedented heatwave affected North-Central India (NCI) during the 2024 pre-monsoon season, with two connected episodes, against the backdrop of the warmest year on record and Pacific sea-surface temperature conditions favorable for extreme heat. This superposition makes it difficult to determine whether the event was driven by natural climate variability or background influence of global warming. To disentangle these influences, we separate the event into atmospheric circulation-driven and residual temperature anomalies, and decompose each into internally generated and externally forced contributions. We find that the event was dominated by internally generated circulation anomalies and residual processes, while externally forced response dampened the intensity of both episodes. Overall, the event evolved from a widespread, circulation-driven heatwave to one dominated by localized land-surface feedback. Given NCI temperature sensitivity to soil moisture, monsoon seasonality and pre-monsoon soil moisture may play an important role in regulating the intensity and future risk of such heatwave amplification.