Role of warming trend in occurrence of record‐breaking high‐temperature events in China during the past 40 years

Abstract Record high temperatures and heatwaves are increasingly being reported worldwide, sparking significant public concern. In a stable climate, occurrences of record‐breaking events (RBEs) should naturally decrease over time. Therefore, the increasing occurrence of record high temperatures signifies significant instability in the current climate change, potentially attributed to global warming. In this study, we aim to quantitatively investigate the impact of the warming trend on RBE occurrence by examining high‐temperature RBEs based on observations in China over the past 40 years. Additionally, we introduce statistical theory based on random processes to assess its applicability to real‐world scenarios. By comparing the frequency, intensity, and waiting time for RBEs derived from the original and detrended high‐temperature series‐, we find that approximately 10% of RBE frequency in Nanjing station over the past 40 years can be linked to the warming trend. Furthermore, the intensity of RBEs weakens and the occurrence time advances for the same reason. Especially, the increase in high‐temperature RBE frequency attributed to the upward temperature trend in the southwest region of China is estimated to be around 10%–20%, significantly surpassing that in other regions. Meanwhile, the observed RBE occurrence probability and intensity align with the theoretical results, while notable discrepancies exist in RBE prediction, highlighting the need for improvement in theory and skill for RBE forecasting given its complexity and uncertainty.