Globally, 2023 was the warmest observed year on record since at least 1850 and, according to proxy evidence, possibly of the past 100 000 years. As in recent years, the record warmth has again been accompanied with yet more extreme weather and climate events throughout the world. Here, we provide an overview of those of 2023, with details and key background causes to help build upon our understanding of the roles of internal climate variability and anthropogenic climate change. We also highlight emerging features associated with some of these extreme events. Hot extremes are occurring earlier in the year, and increasingly simultaneously in differing parts of the world (e.g., the concurrent hot extremes in the Northern Hemisphere in July 2023). Intense cyclones are exacerbating precipitation extremes (e.g., the North China flooding in July and the Libya flooding in September). Droughts in some regions (e.g., California and the Horn of Africa) have transitioned into flood conditions. Climate extremes also show increasing interactions with ecosystems via wildfires (e.g., those in Hawaii in August and in Canada from spring to autumn 2023) and sandstorms (e.g., those in Mongolia in April 2023). Finally, we also consider the challenges to research that these emerging characteristics present for the strategy and practice of adaptation.

从全球范围来看，2023 年是至少自 1850 年以来有记录以来最热的一年，根据代理证据，这可能是过去 10 万年以来最热的一年。与近年来一样，创纪录的高温再次伴随着世界各地更多的极端天气和气候事件。在这里，我们对 2023 年的情况进行了概述，并提供了详细信息和关键背景原因，以帮助我们加深对内部气候变率和人为气候变化的作用的理解。我们还强调了与其中一些极端事件相关的新特征。极端高温天气在今年早些时候发生，并且越来越多地在世界不同地区同时发生（例如，2023 年 7 月北半球同时发生极端高温天气）。强烈的气旋加剧了极端降水（例如，7 月的华北洪水和 9 月的利比亚洪水）。一些地区（例如加利福尼亚州和非洲之角）的干旱已转变为洪水。极端气候还表明，野火（例如夏威夷 8 月和加拿大 2023 年春至秋）和沙尘暴（例如 2023 年 4 月蒙古）与生态系统的相互作用日益增强。最后，我们还考虑了这些新出现的特征给适应策略和实践带来的研究挑战。