Extreme heatwaves pose a significant threat to a wide range of environmental, ecological, and social systems. The rapid warming of the Arctic and the Tibetan Plateau (TP), which are the most prominent features in the Northern Hemisphere in the context of climate change, has significantly influenced mid-latitude extreme events in recent decades. This study utilizes observational data and numerical simulations to demonstrate that the variations in Arctic amplification (AA) and TP amplification (TA) play a crucial role in the interannual variability of summer heatwaves (HWs) in the Yangtze River Basin (YRB) (HWs_YRB) region. The HWs_YRB is associated with a zonally oriented barotropic high-pressure system anchored over the YRB region. The spatial distribution and intensity of the HWs_YRB are impacted by the synergistic effects of AA and TA, via a meridional atmospheric tripole pattern and double jets over East Asia. Furthermore, AA primarily impacts the geographical extent of the HWs_YRB, while TA plays a critical role in determining the intensity of the HWs_YRB. Our findings provide an innovative perspective on the linkage between the pronounced warming observed in the Arctic and TP and the occurrence of summer HWs_YRB, enhancing our comprehension of the climatic consequences of the rapid changes in these two geographical regions.

极端热浪对广泛的环境、生态和社会系统构成重大威胁。北极和青藏高原的快速变暖是气候变化背景下北半球最突出的特征，对近几十年来中纬度极端事件产生了显着影响。本研究利用观测数据和数值模拟证明北极放大（AA）和TP放大（TA）的变化对长江流域（YRB）夏季热浪（HWs）的年际变化起着至关重要的作用（HWs_YRB）地区。 HWs_YRB 与锚定在 YRB 区域上空的纬向正压高压系统相关。 HWs_YRB的空间分布和强度受到AA和TA协同效应的影响，通过东亚经向大气三极格局和双急流。此外，AA主要影响HWs_YRB的地理范围，而TA在确定HWs_YRB的强度方面起着关键作用。我们的研究结果提供了关于北极和青藏高原明显变暖与夏季HWs_YRB发生之间联系的创新视角，增强了我们对这两个地理区域快速变化的气候后果的理解。